Dickinson REC 2025 Annual Report

Photo Credit:

DREC

2025 Annual Report

NDSU Dickinson Research Extension Center Staff

Current Staff-2025

Chris Augustin Director/Soil Scientist

Victor Gomes Extension Cropping Systems Specialist

Cristin Heidecker Administrative Secretary

Krishna Katuwal Research Agronomist

Doug Landblom Associate Research Extension Center Specialist

Eudell Larson Ag Research Technician

Llewellyn Manske Scientist of Rangeland Research

Glenn Martin Research Specialist

Dean Nelson Ag Research Technician

Rutendo Nyamusamba Extension Conservation Agronomist Specialist

Phyllis Okland Administrative Assistant

Samuel Olorunkoya Research Specialist

Garry Ottmar Livestock Research Specialist

Wanda Ottmar Ag Research Technician

Sheri Schneider Information Processing Specialist

Michael Strode Computer Technician

Lee Tisor Research Specialist

Advisory Board

Edward Cuskelly-Chair

Jacob Odermann-Vice-Chair

Dustin Elkins

John Hendrickson

Ryan Kadrmas

Bill Kessel

Kevin Kessel

Mike Gerbig

Chip Poland

Lavy Steiner

Bridget Bullinger

Blake Johnson

NDSU Dickinson Research Extension Center 1041 State Avenue

Dickinson, ND 58601

Phone: (701) 456-1100

Fax. (701) 456-1199

Website: https://www.ndsu.edu/agriculture/ag-hub/research-extension-centers-recs/dickinson-rec Email: NDSU.Dickinson.REC@ndsu.edu

NDSU is a equal opportunity institute.

NDSU does not discriminate in its programs and activities on the basis of age, color, gender expression/identity, genetic information, marital status, national origin, participation in lawful off-campus activity, physical or mental disability, pregnancy, public assistance status, race, religion, sex, sexual orientation, spousal relationship to current employee, or veteran status, as applicable. Direct inquiries to Vice Provost for Title IX/ADA Coordinator, Old Main 201, NDSU Main Campus, 701-231-7708, ndsu.eoaa@ndsu.edu. This publication will be made available in alternative formats for people with disabilities upon request, 701-231-7881.

Table of Contents

2025 Variety Trials

Winter Wheat........................................................................................................................ 5

Barley................................................................................................................................... 6

Durum................................................................................................................................... 7

Field Pea............................................................................................................................... 8

Flax....................................................................................................................................... 9

Barley-New Salem............................................................................................................... 10

Spring Wheat-New Salem..................................................................................................... 11

Oat...................................................................................................................................... 12

Hard Red Spring Wheat........................................................................................................ 13

Organic Hard Red Spring Wheat........................................................................................... 14

Soybean.............................................................................................................................. 15

New Salem Soybean............................................................................................................. 16

Grassland Research

Restoration of Grassland Ecosystems to Full Functionality Requires Replacement

of Traditional Grazing Practices................................................................................... 17

Range Plant Growth Related to Climatic Factors of Western North Dakota, 1982-2024............ 23

Wildryes as Fall Complimentary Pastures for the Northern Plains........................................... 33

Agronomy Research

Determining Soybean Inoculation Strategies in Western North Dakota.................................... 44

Emergence and Early Growth of Hard Red Spring Wheat in Acid Soils of

Western North Dakota................................................................................................. 46

Boron Fertilization to Boost Canola Production in Western North Dakota................................ 53

Managing Soybean Inoculation in Western North Dakota Acidic Soils.................................... 57

Sulfur Fertilizer for Spring Wheat Production in Western North Dakota-Year 3....................... 60

Soil Amendments and Inoculum to Improve Corn Production Under Soil Acidity and

No-Till Dryland System in Western North Dakota........................................................ 62

Lime Impacts on Spring Wheat Yield.................................................................................... 65

Sugarbeet Waste Lime Impacts on Field Pea Aphanomyces.................................................... 66

Livestock Research

Integrated Crop-Livestock System Research Publications: Past, Present, and Future................. 67

Drought Effects on Soil Microbial Activity, pH and Plant Nutrient Activity............................. 69

Extending the Breeding Season: Managing for Increased Profit............................................... 71

DREC Outreach

Outreach List 2025............................................................................................................... 72

Outreach Collaborators and Grants 2025................................................................................ 74

2025 Weekly Updates........................................................................................................... 75

Manning Weather Summary.................................................................................................. 77

Dickinson Weather Summary................................................................................................ 78

Pictures from Field Days 2025.............................................................................................. 79

Restoration of Grassland Ecosystems to Full Functionality Requires Replacement of Traditional Grazing Practices

Llewellyn L. Manske PhD

Scientist of Rangeland Research

North Dakota State University

Dickinson Research Extension Center

Report DREC 25-1202

Traditional grazing practices used to manage Northern Plains grasslands cause serious problems that are so common that most people consider them to be inherent characteristics of the grasslands.

The three serious problems that every grassland managed by traditional grazing practices has are low quantities of available mineral nitrogen which causes the typical reduction of grass herbage production of 49.6% below the biological production level (Wight and Black 1972, 1979). Second year grass lead tillers drop below the nutrient requirements of modern high performance cattle around late July and livestock graze forage that is deficient of nutrients for the remainder of the grazing season. Traditionally managed cows produce milk below their biological potential and their calves gain weight at rates below their genetic potentials.

In order to correct these problems, we need to know both the basic science and the applied science of grassland ecosystems. During the period from early 1970’s through the 1990’s, numerous laboratory physiological scientists described the basic science of the grassland ecosystem biogeochemical processes performed by rhizosphere microbes, and the basic science of the internal grass plant growth mechanisms. These breakthrough scientific discoveries were not reported on the six o’clock news nor in the farm journals, so this important information is not widely known. Unfortunately, these basic physiological scientists did not do the necessary applied science field work to determine how to actually activate the rhizosphere microbes and all of the ecosystem processes and the grass growth mechanisms. That indispensable applied science research was conducted at the NDSU Dickinson REC by the rangeland research program scientist and assistants during the 1980’s and 1990’s.

Traditional grazing practices typically cause the quantity of mineral nitrogen to be available at 30 lbs to 60 lbs/ac, and long-term nongrazed treatments cause the amount of mineral nitrogen to drop to 10 lbs to 30 lbs/ac. In order for Northern Plains grasslands to produce grass herbage at biological potential, the grasslands must be grazed by large graminivores, and the available mineral nitrogen must be at the threshold quantity of 100 lbs/ac or greater (Wight and Black 1972).

Since the last climate change, that occurred around 5,000 years ago (Bluemle 2000) the Northern Plains grasslands have received by deposition at least 2 lbs of nitrogen per acre per year from the effects of the high temperatures of lightning. Nitrogen from lightning has resulted in a wide range of 3 to 8 tons of nitrogen per acre, with most intact grasslands containing 5 to 6 tons of nitrogen per acre (Brady 1974). However, this high amount of nitrogen is in the form of organic nitrogen, which is not available for plant use. Intact grassland soils do not require supplemental nitrogen to be added. Grassland soils require a greater biomass of rhizosphere microbes to transform organic nitrogen into mineral nitrogen (Manske 2018).

A limiting factor for increasing the biomass of rhizosphere microbes is that they do not possess chlorophyll and even if they had access to sunlight, soil microbes cannot capture their own carbon energy. The rhizosphere microbes require an outside source that can provide large quantities of short chain carbon energy before the microbes can increase in biomass. The small amount of carbohydrate leakage from grass plant roots is not enough energy, and the very low amount of 2% to 5% carbohydrate contained in dead grass material is not enough energy to greatly increase the biomass of soil microbes.

Fortunately, the outside source of short chain carbon energy for the soil microbes is conveniently located throughout the grassland. Grass lead tillers capture and fix large quantities of surplus carbohydrate energy during the vegetative growth stages occurring in the early portion of their second year of development. However, this surplus carbohydrate energy is not naturally released into the soil. Exudation of this surplus energy requires specific partial defoliation of lead tillers by large grazing graminivores that removes only 25% to 33% of the aboveground portion of the vegetative growth of grass lead tillers after the 3.5 new leaf stage and before the flower (anthesis) stage each growing season which will slowly release sizable proportions of the lead tiller surplus carbon energy through the roots into the microbial rhizosphere surrounding the grass roots (Manske 2018).

This extremely important outside source of short chain carbon energy will facilitate the rhizosphere microbes to greatly increase their biomass and then be able to transform organic nitrogen into mineral nitrogen, within about three growing seasons, the resulting rhizosphere microbe biomass will be large enough to transform mineral nitrogen at quantities at 100 lbs/ac or greater.

The rhizosphere microorganisms are responsible for the performance of all of the ecosystem nutrient flow activities and for the biogeochemical processes that determine grassland ecosystem productivity and functionality (Coleman et al. 1983).

• Biogeochemical processes transform stored essential elements from organic forms or ionic forms into plant usable mineral forms.
• Biogeochemical processes capture replacement quantities of lost or removed major essential elements of carbon, hydrogen, nitrogen, and oxygen with assistance from active live plants and transform the replacement essential elements into storage as soil organic matter for later use.
• Biogeochemical processes decompose complex unusable organic material into compounds and then into reusable major and minor essential elements (Manske 2018).

The typical grassland problems of low grass herbage biomass production and the annual occurrence of nutrient quality deficiency of grass lead tiller forage after late July can be corrected with full activation of the four main internal grass plant growth mechanisms with partial defoliation by large grazing graminivores that remove 25% to 33% of the aboveground portion of the grass lead tillers at vegetative growth stages after the 3.5 new leaf stage and before the flower (anthesis) stage each growing season (Manske 2018).

The compensatory physiological grass growth mechanisms (McNaughton 1979, 1983, Briske 1991) give grass plants the capability to replace lost leaf and shoot biomass following partial grazing defoliation by increasing meristematic tissue activity, increasing photosynthetic capacity, inhibiting or reducing the rate of senescence, increasing the life span and leaf mass of remaining mature leaves, and increasing allocation of currently fixed carbon and available mineral nitrogen transformed by rhizosphere microbes. Fully activated growth mechanisms can produce replacement foliage at 140% of the herbage weight removed during grazing.

This increase in grass growth activity requires alternative sources of large quantities of carbon and nitrogen. Most of the nitrogen and carbon that was in the shoot is lost during partial defoliation. The preferential alternative source of nitrogen is the mineral nitrogen that has been converted from soil organic nitrogen by active rhizosphere microbes and available in the media around the roots. The alternative source of carbon is currently fixed by photosynthesis in remaining mature leaf and shoot tissue and rejuvenated portions of older leaves. The quantity of leaf area required to fix adequate quantities of carbon is 67% to 75% of the predefoliated leaf area (Manske 1999). Some of this currently fixed carbon is used to produce growth of replacement grass biomass and some of it is moved to the rhizosphere microbes for increased biomass and activity. Eventually, this carbon reaches the soil with an annual input rate of 2.5 tons C/ac.

The vegetative reproduction by tillering mechanisms (Mueller and Richards 1986, Richards et al. 1988, Murphy and Briske 1992, Briske and Richards 1994, 1995) develop secondary tiller shoots from growth of axillary buds on lead tillers. Meristematic activity in axillary buds and the subsequent development of vegetative secondary tillers is regulated by auxin, a growth-inhibiting hormone produced in the apical meristem and young developing leaves which prevents a growth hormone, cytokinin, from activation of the metabolic functions of the axillary buds. Partial defoliation by large grazing graminivores of young leaf material of grass lead tillers at vegetative growth stages temporarily reduces the production of the blockage hormone, auxin, which then allows the cytokinin synthesis or utilization in multiple axillary buds, stimulating the development of vegetative secondary tillers. Activation of secondary tillers from axillary buds on 60% to 80% of the grass lead tillers produce large quantities of vegetative tillers that have adequate nutrient quality that meet the requirements of modern beef cows from mid-July to mid-October each growing season. Vegetative tiller growth is the dominant form of grass reproduction in grasslands (Belsky 1992, Chapman and Peat 1992, Briske and Richards 1995, Chapman 1996, Manske 1999) not sexual reproduction and the development of seedlings. Recruitment of new grass plants developed from seedlings is negligible in healthy grassland ecosystems.

The precipitation water use efficiency mechanisms (Wight and Black 1972, 1979) are highly variable and do not function at an assumed fixed rate for each plant species. The factor that effects the rate of precipitation use efficiency is the quantity of available mineral nitrogen. When mineral nitrogen is available at the threshold quantity of 100 lbs/ac or greater, the grass precipitation use efficiency is fully engaged and highly effective resulting in increased grass herbage biomass production of 50.4% greater per inch of precipitation received than in grasslands with mineral nitrogen available at less than 100 lbs/ac. The efficiency of precipitation use in grass plants function at extremely low levels when mineral nitrogen is deficient below the threshold quantity of 100 lbs/ac. The level of precipitation water use efficiency determines the quantity of grass herbage biomass productivity on grassland ecosystems.

The nutrient resource uptake mechanisms (Crider 1955, Whitman 1974, Li and Wilson 1998, Kochy and Wilson 2000, Peltzer and Kochy 2001) regulate grass plant competitiveness at nutrient and soil water resource uptake and determine the relative dominance of grass plants within a grassland community. Healthy vigorous grass plants have a high nutrient resource uptake efficiency and are superior competitors for mineral nitrogen and soil water and are able to suppress the expansion of shrub rhizomes and prevent successful establishment of invasive shrubs, weedy forbs, and undesirable grass seedlings into the grasslands. However, the use of degrading traditional management practices and the removal of 50% or more of the grass plant aboveground leaf material cause reduced root growth, root respiration, and root nutrient absorption resulting in a reduction of functionality of the grass plants, a diminishment of grass plant health and vigor, a loss of resource uptake efficiency, and a suppression of the competitiveness of grass plants to take up mineral nitrogen, essential elements, and soil water. Undesirable shrub, forb, and grass plants are able to become established within the degraded grass community and then able to uptake the belowground resources no longer consumed by the smaller, less vigorous, deteriorated grass plants, and proportionally increase the undesirable plant biomass production and increase their occupied space in the deteriorated grassland community. Traditionally, the observation of increases of undesirable trees, shrubs, forbs, and grasses into degraded grassland ecosystems would have been explained as a result of fire suppression (Humphrey 1962, Stoddart Smith, and Box 1975, Wright and Bailey 1982) rather than the actual physiological reduction of the grass plant nutrient resource uptake mechanisms.

We now have access to the basic science reports on how the ecosystem biogeochemical processes and the four main grass growth mechanisms work. We know how to increase the biomass of the rhizosphere microbes. We have knowledge from the applied science work on how and when we can activate the biogeochemical processes and the four main grass growth mechanisms to function properly. With the accumulation of all this scientific information, we can replace the detrimental traditional management practices, and develop and establish a biologically effective strategy for proper ecological management of the grasslands of the Northern Plains.

The biologically effective twice-over rotation strategy is designed to coordinate partial defoliation events of large grazing graminivores with grass phenological growth stages, in order to meet the nutrient requirements of the graminivores, the biological requirements of the grass plants and the rhizosphere microbes, to enhance the ecosystem biogeochemical processes, and to activate the four main internal grass plant growth mechanisms for the biologically effective facilitation of grassland ecosystems to full functionality at the greatest achievable levels.

The twice-over rotation grazing strategy uses three to six native grassland pastures. Each pasture is grazed for two periods per growing season. The number of grazing periods is determined by the number of sets of tillers: one set of lead tillers and one set of vegetation secondary tillers per growing season. The first grazing period is 45 days long, ideally, from 1 June to 15 July, with each pasture grazed for 7 to 17 days (never less or more). The number of days of the first grazing period on each pasture is the same percentage of 45 days as the percentage of the total season’s grazeable forage contributed by each pasture to the complete system. The forage is measured as animal unit months (AUM’s). The average grazing season month is 30.5 days long (Manske 2012). The number of days grazed are not counted by calendar dates, but by the number of 24-hr periods grazed from the date and time the livestock are turned out to pasture. The second grazing period is 90 days long, ideally from 15 July to 14 October, each pasture is grazed for twice the number of days as in the first period. The length of the total summer grazing period is best at 135 days; 45 days during the first period plus 90 days during the second period (Manske 2018).

During the first period, partial defoliation that removes 25% to 33% of the leaf biomass from grass lead tillers between the 3.5 new leaf stage and the flower stage increases the rhizosphere microbe biomass and activity, enhances the ecosystem biogeochemical processes, and activates the four main internal grass plant growth mechanisms. Manipulation of these processes and mechanisms does not occur at any other time during the growing season. During the second grazing period, the lead tillers are maturing and declining in nutritional quality, and partial defoliation can remove up to 50% of the leaf biomass. Adequate forage nutritional quality during the second period depends on the activation of the vegetative tillering mechanisms with sufficient quantities of vegetative secondary tiller growth from axillary buds during the first period. Livestock must be removed from intact native grassland pastures in mid October, towards the end of the perennial grass growing season, in order to allow the carryover tillers to store the carbohydrates and nutrients which will maintain plant life functions over the winter. Most of the upright vegetative tillers on grassland ecosystems during the autumn will be carryover tillers which will resume growth as lead tillers during the next growing season. Almost all grass tillers live for two growing seasons, the first season as vegetative secondary tillers, and the second season as lead tillers. Grazing carryover tillers after mid October causes the termination of a large proportion of the grass population, resulting in greatly reduced herbage biomass production in subsequent growing seasons. The pasture grazed first in the rotation sequence is the last pasture grazed during the previous year; i.e. ABC, CAB, and BCA, because the last pasture grazed has the greatest green live herbage weight on 1 June of the start of the following grazing season (Manske 2018).

Acknowledgment

I am grateful to Sheri Schneider for assistance in production of this manuscript.

Literature Cited

Belsky, A.J. 1992. Effects of grazing competition, disturbance and fire on species composition and diversity in grassland communities. Journal of Vegetation Science 3:187-200.

Bluemle, J.P. 2000. The face of North Dakota. 3^rd edition. North Dakota Geological Survey. Ed. Series 26. 206p. 1pl.

Brady, N.C. 1974. The nature and properties of soils. MacMillan Publishing Co., Inc., New York, NY. 639p.

Briske, D.D. 1991. Developmental morphology and physiology of grasses. p. 85-108. in R.K. Heitschmidt and J.W. Stuth (eds.). Grazing management: an ecological perspective. Timber Press, Portland, OR.

Briske, D.D., and J.H. Richards. 1994. Physiological responses of individual plants to grazing: current status and ecological significance. p. 147-176. in M. Vavra, W.A. Laycock, and R.D. Pieper (eds.). Ecological implications of livestock herbivory in the west. Society for Range Management, Denver, CO.

Briske, D.D., and J.H. Richards. 1995. Plant response to defoliation: a physiological, morphological, and demographic evaluation. p. 635-710. in D.J. Bedunah and R.E. Sosebee (eds.). Wildland plants: physiological ecology and developmental morphology. Society for Range Management, Denver, CO.

Chapman, G.P., and W.E. Peat. 1992. An introduction to the grasses. C.A.B. International, Wallingford, UK. 111p.

Chapman, G.P. 1996. The biology of grasses. C.A.B. International, Wallingford, UK. 273p.

Coleman, D.C., C.P.P. Reid, and C.V. Cole. 1983. Biological strategies of nutrient cycling in soil ecosystems. Advances in Ecological Research 13:1-55.

Crider, F.J. 1955. Root-growth stoppage resulting from defoliation of grass. USDA Technical Bulletin 1102. 23p.

Humphrey, R.R. 1962. Range Ecology. The Ronald Press Co. New York, NY. 234p.

Kochy, M., and S.D. Wilson. 2000. Competitive effects of shrubs and grasses in prairie. Oikos 91:385-395.

Li, X., and S.D. Wilson. 1998. Facilitation among woody plants establishing in an old field. Ecology 79:2694-2705.

Manske, L.L. 1999. Can native prairie be sustained under livestock grazing? Provincial Museum of Alberta. Natural History Occasional Paper No. 24. Edmonton, AB. p. 99-108.

Manske, L.L. 2012. Length of the average grazing season month. NDSU Dickinson Research Extension Center. Range Management Report DREC 12-1021c. Dickinson, ND. 2p.

Manske, L.L. 2018. Restoring degraded grasslands. pp. 325-351. in A. Marshall and R. Collins (ed.). Improving grassland and pasture management in temperate agriculture. Burleigh Dodds Science Publishing, Cambridge, UK.

McNaughton, S.J. 1979. Grazing as an optimization process: grass-ungulate relationships in the Serengeti. American Naturalist 113:691-703.

McNaughton, S.J. 1983. Compensatory plant growth as a response to herbivory. Oikos 40:329-336.

Mueller, R.J., and J.H. Richards. 1986. Morphological analysis of tillering in Agropyron spicatum and Agropyron desertorum. Annals of Botany 58:911-921.

Murphy, J.S., and D.D. Briske. 1992. Regulation of tillering by apical dominance: chronology, interpretive value, and current perspectives. Journal of Range Management 45:419-429.

Peltzer, D.A., and M. Kochy. 2001. Competitive effects of grasses and woody plants in mixed grass prairie. Journal of Ecology 89:519-527.

Richards, J.H., R.J. Mueller, and J.J. Mott. 1988. Tillering in tussock grasses in relation to defoliation and apical bud removal. Annals of Botany 62:173-179.

Stoddart, L.A., A.D. Smith, and T.W. Box. 1975. Range Management. 3^rd ed. McGraw-Hill Book Co. New York, NY. 532p.

Whitman, W.C. 1974. Influence of grazing on the microclimate of mixed grass prairie. p. 207-218. in Plant Morphogenesis as the basis for scientific management of range resources. USDA Miscellaneous Publication 1271.

Wight, J.R., and A.L. Black. 1972. Energy fixation and precipitation use efficiency in a fertilized rangeland ecosystem of the Northern Great Plains. Journal of Range Management 25:376-380.

Wight, J.R., and A.L. Black. 1979. Range fertilization: plant response and water use. Journal of Range Management 32:345-349.

Wright, H.A., and A.W. Bailey. 1982. Fire Ecology: United States and southern Canada. John Wiley & Sons. New York, NY. 501p.

Results and Discussion

Literature Cited

Barbour, M.G., J.H. Burk, and W.D. Pitts. 1987. Terrestrial plant ecology. The Benjamin/Cummings Publishing Co., Menlo Park, CA. 634p.

Barker, W.T., and W.C. Whitman. 1988. Vegetation of the Northern Great Plains. Rangelands 10:266-272.

Bluemle, J.P. 1977. The face of North Dakota: the geologic story. North Dakota Geological Survey. Ed. Series 11. 73p.

Bluemle, J.P. 1991. The face of North Dakota: revised edition. North Dakota Geological Survey. Ed. Series 21. 177p.

Brown, R.W. 1977. Water relations of range plants. Pages 97-140. in R.E. Sosebee (ed.) Rangeland plant physiology. Range Science Series No. 4. Society for Range Management. Denver, CO.

Brown, R.W. 1995. The water relations of range plants: adaptations to water deficits. Pages 291-413. in D.J. Bedunah and R.E. Sosebee (eds.). Wildland plants: physiological ecology and developmental morphology. Society for Range Management. Denver, CO.

Coyne, P.I., M.J. Trlica, and C.E. Owensby. 1995. Carbon and nitrogen dynamics in range plants. Pages 59-167. in D.J. Bedunah and R.E. Sosebee (eds.). Wildland plants: physiological ecology and developmental morphology. Society for Range Management. Denver, CO.

Dahl, B.E., and D.N. Hyder. 1977. Developmental morphology and management implications. Pages 257-290. in R.E. Sosebee (ed.). Rangeland plant physiology. Range Science Series No. 4. Society for Range Management. Denver, CO.

Dahl, B.E. 1995. Developmental morphology of plants. Pages 22-58. in D.J. Bedunah and R.E. Sosebee (eds.). Wildland plants: physiological ecology and developmental morphology. Society for Range Management. Denver, CO.

Daubenmire, R.F. 1974. Plants and environment. John Wiley and Sons. New York, NY. 422p.

Dickinson Research Center. 1982-2024. Temperature and precipitation weather data.

Emberger, C., H. Gaussen, M. Kassas, and A. dePhilippis. 1963. Bioclimatic map of the Mediterranean Zone, explanatory notes. UNESCO-FAO. Paris. 58p.

Goetz, H. 1963. Growth and development of native range plants in the mixed grass prairie of western North Dakota. M.S. Thesis, North Dakota State University, Fargo, ND. 165p.

Jensen, R.E. 1972. Climate of North Dakota. National Weather Service, North Dakota State University, Fargo, ND. 48p.

Langer, R.H.M. 1972. How grasses grow. Edward Arnold. London, Great Britain. 60p.

Larson, K.E., A.F. Bahr, W. Freymiller, R. Kukowski, D. Opdahl, H. Stoner, P.K. Weiser, D. Patterson, and

O. Olson. 1968. Soil survey of Stark County, North Dakota. U.S. Government Printing Office, Washington, DC. 116p.+ plates.

Leopold, A.C., and P.E. Kriedemann. 1975. Plant growth and development. McGraw-Hill Book Co. New York, NY. 545p.

Manske, L.L. 1994a. History and land use practices in the Little Missouri Badlands and western North Dakota. Proceedings- Leafy spurge strategic planning workshop. USDI National Park Service, Dickinson, ND. p. 3-16.

Manske, L.L. 1994b. Problems to consider when implementing grazing management practices in the Northern Great Plains. NDSU Dickinson Research Extesion Center. Range Management Report DREC 94-1005, Dickinson, ND. 11p.

Manske, L.L. 1999. Prehistorical conditions of rangelands in the Northern Great Plains. NDSU Dickinson Research Extension Center. Summary Range Management Report DREC 99-3015, Dickinson, ND. 5p.

Manske, L.L. 2011. Range plant growth and development are affected by climatic factors. NDSU Dickinson Research Extension Center. Summary Range Management Report DREC 11-3019c, Dickinson, ND. 5p.

McMillan, C. 1957. Nature of the plant community. III. Flowering behavior within two grassland communities under reciprocal transplanting. American Journal of Botany 44 (2): 144-153.

National Weather Service. 1996. Sunrise and sunset time tables for Dickinson, North Dakota. National Weather Service, Bismarck, ND. 1p.

Odum, E.P. 1971. Fundamentals of ecology. W.B. Saunders Company. Philadelphia, PA. 574p.

Ramirez, J.M. 1972. The agroclimatology of North Dakota, Part 1. Air temperature and growing degree days. Extension Bulletin No. 15. North Dakota State University, Fargo, ND. 44p.

Roberts, R.M. 1939. Further studies of the effects of temperature and other environmental factors upon the photoperiodic response of plants. Journal of Agricultural Research 59(9): 699-709.

Shiflet, T.N. (ed.). 1994. Rangeland cover types. Society for Range Management. Denver, CO. 152p.

Weier, T.E., C.R. Stocking, and M.G. Barbour. 1974. Botany: an introduction to plant biology. John Wiley and Sons. New York, NY. 693p.

Wildryes as Fall Complementary Pastures for the Northern Plains

Llewellyn L. Manske PhD

Scientist of Rangeland Research

North Dakota State University

Dickinson Research Extension Center

Report DREC 25-4032b

Fall Complementary Pastures

The wildryes are the only perennial grass type that retains adequate nutritional quality to meet a lactating cows requirements during fall grazing from mid-October to mid-November. Despite these unique important characteristics, wildryes are not a popular fall pasture in the Northern Plains. The problem isn’t the grasses. The problem is the management. The wildryes do not grow and behave like native grasses of the Northern Mixed Grass Prairie and cannot be managed with the same techniques that the native grasses are managed. The native grasses plus crested wheatgrass and smooth bromegrass grow and behave as if they were types of perennial spring wheat. The wildrye grasses grow and behave as if they were types of perennial winter wheat. Proper management of wildrye fall pastures must be adjusted to accommodate these differences in growth and behavior.

There are numerous types of wildryes in the world. The two common types in the Northern Plains are Altai and Russian Wildryes.

Altai wildrye, Leymus angustus (Trin.) Pilg., is a member of the grass family, Poaceae, tribe, Triticeae, syn.: Elymus angustus Trin., and is a long lived perennial, monocot, cool-season, mid grass, that is drought tolerant, very winter hardy, highly tolerant of saline soils nearly at the level of tall wheatgrass, and fairly tolerant of alkaline soils. Altai wildrye was introduced into Canada as two seed lots. The first seed lot arrived in 1934 from Voronezh, USSR, located in the far western European Russian Steppe. The second seed lot arrived in 1939 from the Steppe of Kustanay located in the northern region of Kazakhstan. Three synthetic strains were developed from seed increase plots started in 1950 at the Swift Current Research Station followed by more sites at seven research stations in Alberta, Manitoba, and Saskatchewan, which produced the first released cultivar, Prairieland, in 1976. Seed from the increase fields at Swift Current was used to establish 60 acres of Altai wildrye monoculture at the NDSU Dickinson Research Extension Center for a replicated study of late season grazing during mid-October to mid-November conducted from 1983 to 2005 for 23 years. Early aerial growth consists of basal leaves from crown tiller buds. Basal leaf blades are 15-25 cm (6-10 in) long, 0.5-0.7 cm wide, erect, coarse, light green to bluegreen to blue, and can remain upright under deep wet snow. The leaf sheath is usually shorter than the internodes and grayish green. The membrane ligule is 0.5-1.0 mm long with an obtuse apex. Some early specimens of introduced strains showed vigorous rhizome charateristics and aggressive spreading which was considered to be undesirable. The available released plant material are generally weakly rhizomatous with short rhizomes. Unfortunately, fields seeded with plant material that has nonaggressive short rhizomes is limited by around a 20 to 25 year life expectancy. However, the uniquely deep extensive fibrous root system that can penetrate to depths of 3-4 m (9.8-13.1 ft) and efficiently absorb available soil water was retained. Regeneration is primarily asexual propagation by crown and short rhizome tiller buds. Seedlings have slow, weak growth and are successful only when competition from established plants is nonexistant. Flower stalks are erect, 60-100 cm (24-39 in) tall, mostly leafless and few in numbers. Inflorescence is a terminal spike 15-20 cm (6-8 in) long, 1 cm in diameter, that has closely spread overlapping spikelets of 2 or 3 florets, with 2 or 3 spikelets per node. Basal leaves are palatable to livestock and seed stalks are not. Wildryes maintain slightly higher levels of protein and digestibility with advancing maturity better than other species of perennial grasses. Wildryes are best used for late season grazing from mid-October to mid-November. Fire top kills aerial parts and kills deeply into the crown when soil is dry. Fire halts the processes of the four major defoliation resistance mechanisms and causes great reduction in biomass production and tiller density. This summary information on growth development and regeneration of Altai wildrye was based on works of Lawrence 1976, and St. John et al. 2010.

Russian wildrye, Psothyrostachys juncea (Fisch.) Nevski., is a member of the grass family, Poaceae, tribe, Triticeae, syn.: Elymus junceus Fisch., and is a long-lived perennial, monocot, cool-season, mid grass, that is exceptionally drought tolerant, tolerant of extremely cold temperatures, highly tolerant of saline soils, fairly tolerant of alkaline soils, intolerant of spring flooding or high water tables, and does not perform well on sandy soils. Russian wildrye was introduced into the United States from Siberia. It was brought to North Dakota in 1907, grown at the Dickinson Research Extension Center in 1913, and grown at the USDA-ARS at Mandan, ND. in 1927. It was introduced into Canada from Siberia in 1926. Early aerial growth consists of basal leaves from crown tiller buds. Basal leaf blades are 7-40 cm (3-16 in) long, 2-6 mm wide, soft, lax, numerous and dense. The split sheath has overlapping margins and open at the top. Previous years sheath bases are persistent and shredded into fibers. The collar is broad and continuous. The membrane ligule is 1 mm long with a blunt flat edge that has numerous small irregular cuts. The small auricles are 2 mm long, clasping, and clawlike. Some plants form no rhizomes, while other plants have several short rhizomes, while other plants have several short rhizomes that form clumps 20-30 cm (8-12 in) wide. Unfortunately, fields seeded with plant material that has nonaggressive short rhizomes is limited by around a 20 to 25 year life expectancy. All bunches have an extensive network of dense, fibrous roots with a lateral spread of 1.2-1.5 m (4-5 ft) that descend downward to 2.5-3.0 m (8-10 ft) deep. About 75% of the root biomass is in the top 15-61 cm (6-24 in) of soil that provides high plant competition to most other species. Regeneration is primarily asexual propagation by crown and short rhizome tiller buds. Seedlings are weak, develop slowly and are successful only when competition from established plants is nonexistant. Flower stalks are erect, hollow, 60-100 cm (24-39 in) tall, mostly leafless and few in number. Inflorescence is a terminal spike 6-11 cm (2.4-4.3 in) long, 5-9 mm wide, that has closely spaced overlapping spikelets of 1 to 4 florets, with 2 or 3 spikelets per node. Flower period in the Great Plains is May and June. Basal leaves are palatable to livestock and seed stalks are not. Wildryes maintain slightly higher levels of protein and digestibility with advancing maturity better than other species of perennial grasses. Wildryes are best used for late season grazing from mid-October to mid-November. Fire top kills aerial parts and kills deeply into the crown when soil is dry. Fire halts the processes of the four major defoliation resistance mechanisms and causes great reduction in biomass production and tiller density. This summary information on growth development and regeneration of Russian wildrye was based on works of Stevens 1963, Dodds 1979, Great Plains Flora Association 1986, Ogle et al. 2005, Taylor 2005, and Johnson and Larson 2007.

Wildryes Require Different Management Practices

Growth characteristics of Altai wildrye is quite different from native cool season grasses. Grazing cool season native grasses during vegetative growth stage prior to the flower stage activates vegetative tiller development from axillary buds. Lightly grazing of Altai wildrye prior to the flower stage did not activate vegetative tillers. Early season grazing actually decreased tiller basal cover. However, fall grazing during mid-October to mid-November that removed 50% or less of the standing leaf biomass greatly increased vegetative secondary tillers and fall tillers that develop during the following summer and early fall.

During early spring, the carryover tillers that survived the winter in the 50% residual herbage biomass of Altai wildrye tussocks regreened providing most of the carbohydrates and energy used for growth of the current leaves of the new seasons lead tillers. Removal of most of the herbage biomass during the fall grazing period causes termination of a major portion of the living crown tillers with greatly reduced active lead tiller growth and critical reductions in herbage biomass and nutritional quality the following growing season.

Lead tillers produce 3.5 new leaves around early June. The seed stalks develop early and are visible before 21 June. The carryover leaves senescence during June. Most of the aboveground herbage biomass weight in June (1668.80 lbs/ac) is the new leaves and stalks of the current lead tillers (figure 11). After the flower stage, the crude protein content of the lead tillers starts to decrease slowly. The vegetative tillers, that have been activated during the previous fall grazing period, begin visible growth shortly after the lead tillers reach the flower stage. The aboveground herbage biomass during July (2210.59 lbs/ac) and August (2291.83 lbs/ac) is the slowly senescent lead tillers and the rapidly growing vegetative tillers. From mid-August to about mid-October, the fall tillers develop and produce the additional herbage biomass during September (3021.91 lbs/ac) and October (3140.89 lbs/ac). By mid-October, the fall tillers should have around 10% to 12% crude protein, the vegetative tillers should have around 10% to 8% crude protein, and the lead tillers should have 8% to 6% crude protein. The ratio of the three tiller types would effect the mean crude protein level of the Altai wildrye forage during the fall grazing period from mid-October to mid-November (table 16, figure 11).

The lead tillers terminate at the end of their second growing season, the year they produce a seed head. The vegetative tillers carryover during the winter and become the next seasons lead tillers. The fall tillers carryover during the winter and become the next seasons vegetative tillers, a few well developed fall tillers may become lead tillers. The survival of the carryover vegetative tillers and fall tillers depends on the amount of leaf area they retain at the end of the fall grazing period. When 50% or more of the aboveground herbage remains on mid-November (1500.00 lbs/ac), most of the vegetative tillers and fall tillers survive to the next spring. However, when greater than 50% of the aboveground herbage is removed by mid November or during an injudicious longer grazing period after mid November, most of the vegetative tillers and fall tillers will have lost greater leaf biomass than they can recover from, resulting in an extremely low survival rate and a rapidly degrading wildrye stand. This devastating reduction in herbage biomass has been incorrectly blamed unto the grass, not on the management practice that truly caused the reductions.

The wildryes do not increase vegetative tiller growth by light grazing during the early vegetative growth stages of lead tillers before the flower stage. So do not graze wildryes during May or June. Vegetative secondary tillers and fall tillers are stimulated by fall grazing from mid-October to mid-November. There is no data of grazing stimulation during mid-September to mid-October. We know that grazing from mid-October to mid-November works when 1500 lbs/ac residual herbage remain from mid-November to spring. That seems like a lot of herbage to leave. Remember that at least 1500 lbs/ac of forage is available to be removed. If the 50% quantity of residual is not remaining at the end of the fall grazing period, the quantity of herbage produced for the next fall grazing period will be much less than the potential 3000 lbs/ac, plus a loss of a potential 1000 lbs/ac to 2000 lbs/ac in additional herbage that could be produced when the grasses remain healthy. The residual of 1500 lbs/ac must remain or your management will fail the vegetation, the stand will deteriorate in 20 to 25 years, and the grass receives the blame. By leaving 50% residual annually, the wildrye stand life expectancy could be perpetual. This will require another long-term research study.

Performance of Grass and Livestock

Altai wildrye is an excellent fall pasture during mid-October to mid-November. The wildryes have been considered to be difficult to grow because they respond differently than the native grasses and common domesticated grasses to standard grassland practices. The wildryes are different and require different management practices. The wildryes are not the problem. The standard management practices are the problem. With 27 years of research, the problems with the standard practices can be corrected.

Four different forage sources for fall complementary pastures have been evaluated that compared two perennial grass forage types and compared two cropland forage types. Two biologically effective fall complementary pastures are Altai wildrye (perennial grass) and Spring Seeded Winter Cereal (cropland). Two traditional fall pastures are Native Rangeland (perennial grass) and Cropland Aftermath (cropland).

The biologically effective fall complementary perennial grass pasture was Altai wildrye. Cow and calf pairs grazed one pasture of Altai wildrye (replicated two times) at 1.41 ac/AUM for 30 days (1.39 ac/AU) from mid-October to mid-November (table 17).

The traditional fall complementary perennial grass pasture was native rangeland. Cow and calf pairs grazed one pasture of native rangeland (replicated two times) at 4.11 ac/AUM for 30 days (4.04 ac/AU) from mid-October to mid-November (table 17).

The one pasture traditional concept of native rangeland provided 891 lbs/ac herbage during the mid-October to mid-November grazing period leaving a residual of 668 lbs/ac, which would indicate a utilization rate of 223 lbs/ac. There is no new growth of native rangeland after mid October and leaf senescence is greatly accelerated, with nutritional quality below a lactating cows crude protein requirements.

The one pasture biologically effective concept of Altai wildrye provided 3141 lbs/ac herbage during the mid-October to mid-November grazing period leaving a residual of 1496 lbs/ac, which would indicate a utilization rate of 1645 lbs/ac. The residual herbage would include highly senescent lead tiller leaves that would contain 8% to 6% crude protein, secondary vegetative tiller leaves that would contain 10% to 8% crude protein, and fall tiller leaves that would contain 12% to 10% crude protein. Some of the residual would contain the totally senescent seed heads of which the cows do not consume.

On the Altai wildrye strategy, calf weight gain was 1.82 lbs per day, 37.12 lbs per acre, and accumulated weight gain was 50.34 lbs per head. Cow weight gain was 1.62 lbs per day, 32.22 lbs per acre, and accumulated weight gain was 42.60 lbs per head (table 18).

On the native rangeland strategy, calf weight gain was 0.59 lbs per day, 4.38 lbs per acre, and accumulated weight gain was 17.73 lbs per head. Cow weight loss was 1.74 lbs per day, 12.90 lbs per acre, and accumulated weight loss was 52.20 lbs per head (table 18).

Cow and calf weight performance on the Altai wildrye strategy was greater than those on the native range strategy. The calf weight gain per day was 208.47% greater, gain per head was 183.93% greater, and gain per acre was 747.49% greater. The cow weight gain per day was 193.10% greater, gain per head was 181.61% greater, and gain per acre was 349.77% greater (table 18).

Pasture costs were 65.58% lower and cost per day were 65.25% lower on the Altai wildrye strategy than those on the native range strategy (table 17). The dollar value captured was greater on the Altai wildrye strategy, pasture weight gain value was 183.96% greater, net return per cow-calf pair was 200.35% greater, and net return per acre was 391.56% greater, while cost per pound of calf gain was 87.94% lower, than those on the native range strategy (table 18).

The biologically effective fall complementary cropland pasture was spring seeded winter cereal. Cow and calf pairs grazed four pastures of spring seeded winter rye with each pasture grazed for one week (replicated two times) at 0.48 ac/AUM for 30 days (0.47 ac/AU) from mid-October to mid-November (table 19).

The traditional fall complementary cropland pasture was cropland aftermath of annual cereal residue of oat and/or barley stubble. Cow and calf pairs grazed one pasture of cereal residue forage (replicated two times) at 6.74 ac/AUM for 30 days (6.63 ac/AU) from mid-October to mid-November (table 19).

The one pasture traditional concept of cropland aftermath provided 270 lbs/ac herbage during the mid-October to mid-November grazing period leaving a residual of 135 lbs/ac, which would indicate a utilization rate of 135 lbs/ac. The nutrient content of stubble from annual cereal harvested for grain is almost nonexistent and lactating cows cannot find forage that meets their crude protein requirements.

The four pasture biologically effective concept of spring seeded winter cereal provided 1908 lbs/ac forage during the mid-October to mid-November grazing period leaving no standing residual vegetation. The livestock had access to one fresh pasture per week with reuse of previous pastures.

On the spring seeded winter cereal strategy, calf weight gain was 2.00 lbs per day, 127.66 lbs per acre, and accumulated weight gain was 60.00 lbs per head. Cow weight gain was 1.05 lbs per day, 67.02 lbs per acre, and accumulated weight gain was 31.50 lbs per head (table 20).

On the cropland aftermath strategy, calf weight gain was 0.42 lbs per day, 1.90 lbs per acre, and accumulated weight gain was 12.57 lbs per head. Cow weight loss was 1.61 lbs per day, 7.27 lbs per acre, and accumulated weight loss was 48.17 lbs per head (table 20).

Cow and calf weight performance on the spring seeded winter cereal strategy was greater than those on the cropland aftermath strategy. The calf weight gain per day was 376.19% greater, gain per head was 377.33% greater, and gain per acre was 6618.95% greater. The cow weight gain per day was 165.22% greater, gain per head was 165.39% greater, and gain per acre was 1021.87% greater (table 20).

Pasture costs were 48.57% greater and cost per day were 50.00% greater on the spring seeded winter cereal strategy than those on the cropland aftermath strategy (table 19). Even though the pasture costs were higher, the dollar value captured was greater on the spring seeded winter cereal strategy, pasture weight gain value was 377.27% greater, net return per cow-calf pair was 600.00% greater, and net return per acre was 7182.09% greater, while cost per pound of calf gain was 68.57% lower, than those on the cropland aftermath strategy (table 20).

Grazing native rangeland after mid October and grazing cropland aftermath of annual cereal residue stubble are old style traditional forage management practices previously used with low-performance livestock that do not work biologically nor economically with modern high-performance livestock. Both practices are deficient at providing adequate forage quality and inefficient at nutrient capture. The cows lose considerable weight and the calf weight gain is diminutive resulting in negative net returns (tables 18 and 20).

Literature Cited

Dodds, D.L. 1979. Common grasses and sedges in North Dakota. NDSU Extension Service R-658. Fargo, ND.

Great Plains Flora Association. 1986. Flora of the Great Plains. University of Kansas, Lawrence, KS.

Johnson, J.R., and G.E. Larson. 2007. Grassland plants of South Dakota and the Northern Great Plains. South Dakota University. B 566 (rev.). Brookings, SD.

Lawrence, T. 1976. Prairieland, Altai wildryegrass. Canadian Journal of Plant Science 56:991-992.

Ogle, D., L. St. John, J. Cornwell, L. Holzworth, M. Majerus, D. Tober, K.B. Jensen, and K. Sanders. 2005. Psothyrostachys juncea (Fisch.) Nevski. Plant Database. USDA. Natural Resources Conservation Services. Boise, ID. http://plants.usda.gov/

St. John, L., D.G. Ogle, W. Duckwitz, and D. Tober. 2010. Plant Guide for Altai wildrye (Leymus angustus). USDA. Natural Resources Conservation Service. Aberdeen, ID. http://plants.usda.gov/

Stevens, O.A. 1963. Handbook of North Dakota plants. North Dakota Institute for Regional Studies. Fargo, ND.

Taylor, J.E. 2005. Psothyrostachys juncea. Fire Effects Information System. USDA. Forest Service. http://www.fs.fed.us/database/feis/

Determining Soybean Inoculation Strategies in Western North Dakota

Victor Gomes

Extension Cropping Systems Specialist Dickinson Research Extension Center

victor.gomes@ndsu.edu; 701.456.1102

Introduction

Soybean (Glycine max L.) production in western North Dakota remains challenging because of the limiting environmental conditions and because the crop is relatively new to the region, and locally validated agronomic recommendations are limited. With soybean acreage in the region having more than doubled over the past decade (USDA-NASS, 2024), the need for region specific inoculation and nitrogen management recommendations become more crucial.

One of the most critical knowledge gaps in supporting soybean expansion into “soybean-virgin” soils is understanding how to effectively use Bradyrhizobium inoculants to maximize biological nitrogen fixation (BNF) and reduce dependence on costly nitrogen fertilizers. More than half of soybean nitrogen requirements are typically supplied through symbiosis with Bradyrhizobium, with the remainder obtained from soil mineralization or fertilizer inputs (Salvagiotti et al., 2008). For example, a 40 bu/ac soybean crop requires roughly 200 lb N/ac, illustrating the magnitude of nitrogen inputs required for sustainable production (Tamagno et al., 2018).

Farmers currently have access to several inoculation products and application methods, including peat, liquid, and granular formulations. However, limited data exist on which products and rates perform best under the distinct soil and climatic conditions of western North Dakota. Moreover, inoculation effectiveness is known to vary with initial soil nitrogen levels and with the presence—or absence—of native rhizobia populations. In newly cultivated soybean fields, these populations are often low or absent, making inoculation critical for establishing an effective symbiosis.

Therefore, research is needed to determine the most efficient inoculant sources and application rates under varying soil nitrogen conditions.

Material and Methods

To identify the most effective inoculation strategies for maximizing soybean production in western North Dakota, this study evaluated the performance of liquid and granular inoculants derived from different rhizobia strains—Bradyrhizobium japonicum (liquid) and B. elkanii (granular)—applied at varying rates and in combination with a starter nitrogen fertilizer treatment. This trial was conducted at the Dickinson REC, in a field with no soybean history.

The experiment included the following treatments:

• Three inoculation rates (1×, 2×, and 3× the label recommendation) for both liquid and granular formulations (six treatments total);

• Two treatments combining the 1× inoculation rate (liquid or granular) with 20 lb N/ac starter fertilizer to simulate field starting-nitrogen differences;

• One treatment combining 1× liquid and 1× granular inoculants to evaluate potential strain complementarity;

• Two controls: an untreated control and a control with 20 lb N/ac starter fertilizer.

In total, 11 treatments were evaluated using a randomized complete block design with four replications at each site.

The soybean variety was ND170009GT, treated with a fungicide (Allegiance^®). The inoculation treatments were mixed in the seed envelopes prior to planting. All other agronomic management followed the NDSU’s soybean production field guide (Kandel & Endres, 2023). Soybean was solid seeded at 145,000 seeds acre^-1 on May 12 and was harvested on Oct. 3.

Grain yield, oil, and protein content data were determined.

Results

Soybean yield, protein, and oil content were influenced by inoculant type, rate, and the use of starter fertilizer (Table 1). In general, inoculated treatments outperformed the non-inoculated check, confirming the importance of rhizobial inoculation in recently introduced soybean-growing areas such as western North Dakota.

Grain yield ranged from 31.0 to 40.8 bu/ac. The greatest yields were obtained by the 1× Liquid, 3× Liquid, 2x Granular, 3x Granular, and 1× Granular + 20 lbs N/ac treatments, which were statistically similar and significantly greater than the untreated check. These results suggest that both liquid and granular inoculants are effective at improving yield under the study conditions.

Protein content varied from 31.30 to 35.63%, while oil ranged from 16.69 to 17.94%. The 3× Granular treatment had the greatest protein concentration (35.63%). Greater protein levels were often associated with lower oil concentrations, consistent with the typical inverse relationship between these two seed components.

The check and nitrogen-only treatments showed lower protein and moderate-to-high oil content, reinforcing that biological nitrogen fixation contributes more effectively to protein accumulation than small additions of inorganic N.

Means followed by the same letter within a column are not significantly different according to the least significant difference (LSD) test.

Conclusions

• Inoculation significantly improved soybean yield compared to the untreated check, confirming the necessity of Bradyrhizobium inoculation in western North Dakota soils lacking native rhizobia populations.
• Liquid and granular inoculants performed similarly in yield, though higher granular inoculant rates (3×) tended to enhance protein content, likely offsetting the inhibitory effect of elevated soil nitrate (45 lbs N/ac) on nodulation.
• The study will be replicated at least for one more year to confirm the results, as only one year of the trial is not sufficient to draw impactful conclusions and recommendations.

Acknowledgements

This study was sponsored by the North Dakota Soybean Council.

References

Bais, J., Kandel, H., DeSutter, T., Deckard, E., & Keene, C. (2023). Soybean response to N fertilization compared with co-inoculation of Bradyrhizobium japonicum and Azospirillum brasilense. Agronomy, 13(8), 2022.

Forster, S., Goos, R. J., Teboh, J. M., Augustin, C. L., Zilahi-Sebess, S., Aberle, E., & Henson, B. (2016) Correlating a Ureide Tissue Test for Soybean with Field Inoculation Studies. [Abstract]. ASA, CSSA and SSSA International Annual Meetings (2016), Phoenix, AZ. https://scisoc.confex.com/scisoc/2016am/meetingapp.cgi/Paper/100597;&nb…;

Kandel, H. & Endres, G. (ed.) (2023). North Dakota Soybean Production Field Guide. North Dakota State University Extension. Publication A1172.

F. Salvagiotti, K.G. Cassman, J.E. Specht, D.T. Walters, A. Weiss, A. Dobermann, Nitrogen uptake, fixation and response to fertilizer N in soybeans: A review, Field Crops Research, Volume 108, Issue 1, 2008, Pages 1-13, ISSN 0378-4290, https://doi.org/10.1016/j.fcr.2008.03.001.

Tamagno, S., Sadras, V. O., Haegele, J. W., Armstrong, P. R., & Ciampitti, I. A. (2018). Interplay between nitrogen fertilizer and biological nitrogen fixation in soybean: implications on seed yield and biomass allocation. Scientific Reports, 8(1), 17502. https://doi.org/10.1038/s41598-018-35672-1.

USDA National Agricultural Statistics Service (2024). NASS - Quick Stats. USDA National Agricultural Statistics Service. Dataset. USDA/NASS QuickStats Ad-hoc Query Tool.

Emergence

The emergence rate index (ERI) varied significantly (p < 0.05) among the evaluated HRSW varieties and the variety SD Ascend exhibited the greatest ERI (33.5), indicating the fastest emergence rate (Table 1). A higher ERI reflects a quicker and more uniform emergence, which favors rapid canopy development, improved early-season competition with weeds, and overall better stand establishment.

In contrast, SD Brawn and ND Roughrider recorded the lowest ERI values (17.70 and 13.44, respectively) and where statistically lower than all the other varieties. The lower ERI’s observed for these varieties may suggest a greater susceptibility to acidic soil conditions and potential aluminum toxicity.

Despite Lanning’s known genetic tolerance to aluminum toxicity and low soil pH, it did not outperform the other varieties in terms of ERI, including those that do not carry the TaAlmt1 gene responsible for aluminum tolerance. Fordyce et al. (2020) similarly reported that regionally adapted TaAlmt1 carriers did not outperform adapted noncarriers under field conditions. However, more positive results were observed for Lanning in terms of final emergence, where this variety outperformed the susceptible check and most other varieties.

Final emergence (%) did not differ significantly among varieties, ranging from 80% for ND Roughrider and 100% for SD Ascend. Despite the lack of statistical differences in total emergence, the variation in ERI underscores differences in early seedling vigor and tolerance to acidic soil conditions among the tested varieties.

Means followed by the same letter within a column are not significantly different according to the least significant difference (LSD) test at 5%.

Early Growth

Among the evaluated hard red spring wheat (HRSW) varieties, only plant height, root length, and root fresh weight varied significantly (p < 0.05) (Table 2). Culm diameter averaged 1.7 mm, tops fresh weight 9.5 g, tops dry matter 1.6 g, root dry matter 2.5 g, and crop growth stage averaged Zadoks 17 across varieties.

Overall, SD Ascend outperformed all other varieties in terms of plant height, root length, and root fresh weight. The superior early growth performance of SD Ascend is consistent with its rapid emergence and likely reflects greater vigor and adaptation to acidic soil conditions.

Aluminum toxicity primarily targets the root apex, where Al exposure inhibits cell elongation and division, resulting in root stunting and impaired water and nutrient uptake (Panda et al., 2009). Consequently, root length is often used as an indicator of Al susceptibility or tolerance. In this study, varieties MT Dutton, ND Frohberg, ND Thresher, and SD Brawn exhibited the shortest roots, suggesting a higher sensitivity to aluminum toxicity. MT Dutton has been described as exhibiting partial/moderate tolerance to aluminum and acidic soils (Cook et al., 2023). However, we observed relatively short root length for MT Dutton under our experimental conditions (pH 4.8), suggesting that its tolerance may be limited under more severe acid stress or may be environment-dependent.

Root fresh weight also differed significantly among varieties (p < 0.05). SD Ascend had the greatest root fresh weight, confirming its superior vigor and ability to maintain active root growth under stress. In contrast, ND Frohberg, ND Thresher, and SD Brawn produced the lowest root fresh weights, consistent with their reduced root length.

Lanning also showed low root fresh weight despite showing intermediate root length. This discrepancy suggests that while Lanning was able to sustain primary root elongation under acidic conditions, its overall root biomass accumulation was limited. Such a response could indicate a reduced development of lateral roots or a lower root tissue density, both of which are common adaptive trade-offs observed in aluminum-tolerant genotypes (Kochian et al., 2015). Aluminum exclusion mechanisms, such as those mediated by the TaALMT1 gene, may protect the root apex but do not necessarily promote biomass accumulation if carbon allocation to roots is constrained under stress. Consequently, Lanning’s moderate elongation combined with lower root mass may reflect a tolerance mechanism centered on maintaining root function rather than vigorous root growth under low pH stress.

Root biomass accumulation represents an integrated response to both root elongation and lateral root proliferation. Varieties able to maintain greater root fresh weight under low pH likely possess more efficient carbon allocation to belowground tissues and enhanced physiological resilience against aluminum-induced growth inhibition. Conversely, reduced root biomass may limit nutrient and water uptake capacity, potentially constraining shoot development and yield potential under field conditions (Ofoe et al., 2023).

The variation observed in root fresh weight complements differences in emergence and early growth, highlighting genetic variability in tolerance to soil acidity and aluminum toxicity among the tested HRSW varieties.

Means followed by the same letter within a column are not significantly different according to the least significant difference (LSD) test at 5%.

Conclusions

• SD Ascend consistently demonstrated superior performance in terms of emergence rate, plant height, root length, and root biomass, indicating strong adaptation and vigor under acidic soil conditions.
• Varieties such as ND Frohberg, ND Thresher, and SD Brawn showed sensitivity to acidic conditions, exhibiting both shorter roots and lower root biomass, implying reduced ability to cope with aluminum stress.
• Variety selection represents a viable short-term management strategy for producers facing acid soils in western North Dakota, offering an immediate alternative while long-term liming solutions remain limited.
• The trial will be repeated one more time to confirm the results, as only one run of the trial is not sufficient to draw impactful conclusions and recommendations.

References

Cook, J., Heo, H., Blake, N., Lile, J., Wong, M., Nash, D., Holen, D., Torrion, J., Larson, D., McVey, K., Khan, Q., Eberly, J., Hammontree, J., Vetch, J., Medina, W., Lamb, P. F., Haney, E., Runner, T., Chen, C., … Kowatch, C. (2023). SPRING WHEAT VARIETY PERFORMANCE SUMMARY IN MONTANA.

Fordyce, S., Jones, C. A., Dahlhausen, S. J., Lachowiec, J., Eberly, J. O., Sherman, J. D., McPhee, K. E., & Carr, P. M. (2020). A simple cultivar suitability index for low-pH agricultural soils. Agricultural & Environmental Letters, 5(1), e20036. https://doi.org/10.1002/ael2.20036

Kochian, L. V., Piñeros, M. A., Liu, J., & Magalhaes, J. V. (2015). Plant Adaptation to Acid Soils: The Molecular Basis for Crop Aluminum Resistance. Annual Review of Plant Biology, 66(Volume 66, 2015), 571–598. https://doi.org/10.1146/annurev-arplant-043014-114822

Ofoe, R., Thomas, R. H., Asiedu, S. K., Wang-Pruski, G., Fofana, B., & Abbey, Lord. (2023). Aluminum in plant: Benefits, toxicity and tolerance mechanisms. Frontiers in Plant Science, 13, 1085998. https://doi.org/10.3389/fpls.2022.1085998

Panda, S. K., Baluska, F., & Matsumoto, H. (2009). Aluminum stress signaling in plants. Plant Signaling & Behavior, 4(7), 592–597. https://doi.org/10.4161/psb.4.7.8903

Acknowledgment

This study was sponsored by the North Dakota Weed Commission

Agronomy Research

Boron Fertilization to Boost Canola Production in Western North Dakota

Victor Gomes

Extension Cropping Systems Specialist Dickinson Research Extension Center

victor.gomes@ndsu.edu; 701.456.1102

Introduction

In recent years, canola acreage has significantly expanded in western North Dakota due to market downturns for small grains and advancements in cultivar traits. However, canola production in North Dakota is significantly impaired by plant nutrient availability, including micronutrients. Boron (B) is a critical nutrient for canola, as the crop is a heavy user of B and is highly sensitive to its deficiency.

Boron deficiency, although rare, typically occurs in sandy areas of fields. This deficiency may be exacerbated by aluminum toxicity to roots, a condition commonly associated with acidic sandy soils—an issue that is becoming increasingly prevalent in western North Dakota. According to AGVISE Laboratories, Inc. (2024), soil samples with soil test boron below 0.4 ppm in 2024 in western North Dakota were between 16-44%.

The current recommendation for boron application in North Dakota is 2 lbs/acre for canola. However, this recommendation is based on data generated in northeast North Dakota, a region characterized by cooler and more humid conditions compared to the semi-arid climate of western North Dakota. While claims of boron fertilization benefits in canola production exist, scientific evidence supporting these claims remains inconclusive, with inconsistent effects observed on yield, protein content, and oil quality.

To address this knowledge gap, the objective of this study is to evaluate the effects of different rates, timings, and modes of boron application on the yield and seed quality of canola in western North Dakota. This research aims to provide region-specific recommendations that optimize canola production and address nutrient management challenges in the area.

Material and Methods

Field experiments were conducted at the Dickinson Research Extension Center and the North Central Research Extension Center (Minot, ND). A randomized complete block design, with four replications was used. Treatments consisted of either three rates of granular B fertilizer (2, 5 and 10 lbs B ac^-1) broadcasted after planting, or a foliar B application at 10-20% bloom stage at three different rates (0.25, 0.50 and 1 lbs B ac^-1), or the combination of a granular application at planting (1lbs ac^-1) and a foliar application at 10-20% bloom (0.25 and 0.50 lbs ac^-1) plus a zero B control treatment.

The canola hybrids were InVigor^® L345PC in Dickinson and DK400TL in Minot. In both locations, plots were solid seeded with a no-till drill. The seeding rate in Dickinson was 600,000 plants acre^-1 and Minot it was 450,000 plants acre^-1. Prior to planting, soil samples were pulled from the experimental area for soil chemical and physical analysis. Preference was given for fields deficient in Boron (B < 0.5 ppm).

In Dickinson, all plots received a baseline fertilization with 120 lbs. ac^-1 Nitrogen as Urea and 20 lbs. ac^-1 Sulfur as ammonium sulfate. In Minot, the plots received 150 lbs. ac^-1 N (urea plus Anvol^™), 50 lbs. ac^-1 Phosphorus (MAP), and 30 lbs. ac^-1 Sulfur (ammonium sulfate).

In Dickinson, granular boron at the rate of 0, 1, 2, 5 or 10 lbs B ac^-1 was broadcasted immediately after seeding in each corresponding experimental plot. In Minot, those same rates of granular boron were placed in furrow. At 10-20% bloom stage, the remainder of the treatments received a foliar spray of Boron (Solubor^®, Sodium Borate 20.5%), at 0.25, 0.50 and 1 lbs B ac^-1, using a backpack sprayer.

Each experimental unit measured 10 ft x 30 ft (300 ft²). Local air temperatures and precipitation were quantified using NDAWN weather stations.

At the end of the growing season (after physiological maturity), plants in the central rows of each plot were mechanically harvested and quantified for grain yield, harvest moisture content, test weight, and, seed composition analysis (i.e., seed oil content), due to the importance of seed quality for end users.

Data was analyzed through an analysis of variance using a mixed-model approach (PROC GLIMMIX) in SAS 9.4. Within each site, the fixed factors were be fertilizer rates, timing and modes of application. The random factor was replication.

Results

Soil pH was moderately acidic at Dickinson (5.5) and near neutral at Minot (6.5), which may influence boron availability and uptake (Table 1). Boron concentrations were low and similar between sites (0.35 ppm at Dickinson and 0.44 ppm at Minot). However, boron soil tests are known to be highly variable and often unreliable (Marupaka et al., 2022).

Both in Dickinson and Minot, a large precipitation (>2 inches) was recorded in the days following canola seeding, which resulted in poor plant establishment. In Dickinson, the plant population was 317,462 plants acre^-1, equivalent to 53% of the target plant population.

Significant differences in grain yield (p < 0.05) were observed only at the Dickinson site (Table 1). Seed oil content was not significant (p > 0.05) in any of the locations.

Grain yield at Dickinson responded positively to boron fertilization, with treatments producing higher yields than the untreated check. The combination of granular and foliar boron (1 lb/ac granular + 0.25 lb/ac foliar) resulted in the highest yield (2,351 lbs/ac), significantly outperforming the check (25% yield increase). The lowest rate treatment (0.25 lbs/a foliar) still provided a 14% yield increase in Dickinson.

Treatments with either foliar or granular boron alone generally showed intermediate yield gains. This could be due to the fact that canola plants need a steady supply of boron throughout the growing season, and one single application at planting may not be sufficient to meet the crop needs during the reproductive stages, when the plant’s boron demand increases (Ma et al., 2019).

In Minot, while the results were not statistically significant, we could still observe a yield gain trend with the different treatments compared to the control. The treatment consisting of 0.50 lbs B acre^-1 had the greatest yield overall (2,448 lbs ac^-1), with a 14% increase compared to the control treatment.

Overall, the results suggest that low rates and combined application methods tended to be more effective than single-source applications in enhancing canola yield under the conditions at Dickinson.

Means followed by the same letter within a column are not significantly different according to the least significant difference (LSD) test at 5%.

Conclusions

• The effects of Boron fertilization in canola yield seem to be positive.
• The combination of a granular B application at planting plus a foliar B application at 10-20% bloom produced the best results.
• This correlation, however, seems to be location dependent.
• Boron sources, rates and timing of application do not affect seed oil content in canola.
• The study will be conducted again next year to confirm the results and to provide more sound recommendations to canola growers.

Acknowledgments

This study was sponsored by the Northern Canola Growers Association.

References

AGVISE Soil Test Summary 2024 Minnesota, North Dakota South Dakota, Manitoba Regional summary of residual soil nitrate after major crops and soil test nutrient levels (2024). Available at: https://www.agvise.com/wp-content/uploads/2024/11/agvise-soil-test-summ…

Ma, B.-L., Zheng, Z., Whalen, J. K., Caldwell, C., Vanasse, A., Pageau, D., Scott, P., Earl, H., & Smith, D. L. (2019). Uptake and nutrient balance of nitrogen, sulfur, and boron for optimal canola production in eastern Canada. Journal of Plant Nutrition and Soil Science, 182(2), 252–264. https://doi.org/10.1002/jpln.201700615

Marupaka, V., Mylavarapu, R. S., Bergeron, J., Smidt, S. J., Hochmuth, G. J., & van Santen, E. (2022). Comparing Boron Soil Testing Methods for Coastal Plain Sandy Soils. Communications in Soil Science and Plant Analysis, 53(12), 1456–1472. https://doi.org/10.1080/00103624.2022.2046041

Managing Soybean Inoculation in Western North Dakota Acidic Soils

Victor Gomes¹; Chris Augustin²

¹Extension Cropping Systems Specialist, Dickinson Research Extension Center

²Director, Dickinson Research Extension Center

victor.gomes@ndsu.edu; 701.456.1102

Summary:
Soybean production in western North Dakota is challenged by the lack of native Rhizobium populations and increasing soil acidity caused by long term no-till associated with ammonia-based fertilizers. Acidic soils reduce Rhizobium survival, limiting nodulation and nitrogen fixation. This study examines the interaction between soil pH and inoculant type to improve soybean establishment and symbiotic performance under low pH soil conditions.

Objective:
Evaluate the performance of three commercial soybean inoculants under varying soil pH conditions to identify Rhizobium strains most tolerant to acidity and suitable for western North Dakota soils.

Methods:
Soybean variety ND17009GT was grown in 1-gallon pots under controlled conditions in a growth chamber simulating early-season weather in Stark County. Seeds received one of three inoculant treatments:

• Granular: LAL FIX Start (B. elkanii)
• Liquid: BYSI-N (B. japonicum)
• Peat: N-Charge Soybean (B. japonicum)
  A non-inoculated control was also included.

In the spring, soil from a collaborating farmer field was collected. Soil pH was 5.1. The soil was placed in 1-gallon pots and adjusted to four pH levels (4.7, 5.1, 5.5, 6.0) using either aluminum sulfate to acidify the soil or pelletized lime to increase the soil pH. Emergence, nodulation, and early growth traits were evaluated.

Results

Emergence rate and final emergence were influenced by both inoculant and pH, though not their interaction (Table 1). Inoculated treatments had higher emergence (>85%) than the control (77%). Slightly acidic soils (pH 5.1–5.5) favored faster and more uniform emergence compared to strongly acidic (pH 4.7) or neutral (pH 6.0) soils.

Means followed by the same letter within a column are not significantly different according to the least significant difference (LSD) test at 5%.

Soybean early growth was influenced by soil acidity only (Table 2). Plants at pH 4.7 were elongated (etiolated) and had thinner stems, indicating stress and possible aluminum toxicity.

Means followed by the same letter within a column are not significantly different according to the least significant difference (LSD) test at 5%.

The number of nodules per plant and the weight of nodules per plant varied significantly as a function of the interaction between inoculants and pH levels (p < 0.05) (Table 4). Overall, it was observed that the granular inoculant produced the greatest number of nodules per plant, followed by the liquid inoculant. Statistically, the peat inoculant was similar to the untreated check in terms of number of nodules.

One possible reason for the superior performance of the granular inoculant is the presence of Bacillus velezensis in its formulation. B. velezensis is known to promote phosphorus (P) solubilization, increasing the amount of plant-available P in the soil solution. In acidic soils, aluminum (Al³⁺) readily reacts with phosphate ions, forming insoluble aluminum phosphates and thereby reducing P availability to plants. By solubilizing P, B. velezensis may indirectly mitigate Al toxicity’s suppression of root growth and nodule formation. This mechanism may help explain the greater nodule numbers observed with the granular inoculant.

Support for this mechanism is found in the work of Buetow (2022), who reported that in furrow-applied phosphorus trials on acid-affected soils (pH < 5.5) in western North Dakota, adding P improved yield responses in a susceptible hard red spring wheat variety, suggesting P availability can alleviate some of the constraints imposed by low pH and Al toxicity. Similarly, a report from Oklahoma State University showed that in acid Oklahoma soils (pH < 5.5) banding P fertilizer significantly reduced Al toxicity and improved root performance in winter wheat.

In terms of weight of nodules, it was observed a linear growth for the granular inoculant that followed the pH increase. For the liquid inoculant, the weight of nodules at pH 5.1 was the greatest across all treatments. The peat inoculant had low nodule weight, being for the most part similar to the untreated check.