Title

Weed control and soybean response to preemergence application of metribuzin and sulfentrazone at Hettinger, ND, 2025.

(Research Report, Hettinger REC, December 2025)

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Publication File:

Summary

Two trials were conducted to evaluate weed control and soybean tolerance soybean following preemergence application of metribuzin and sulfentrazone (Spartan). Soybean were planted on June 3. Prior to planting the field was treated with paraquat (Gramoxone) to control weeds that were present prior to planting. In one trial, weeds were allowed to grow following herbicide application to determine levels of weed control. In order to determine yield, an application of glufosinate (Liberty) was applied following the final weed control evaluation (57 days after treatment). In the other trial, soybean were maintained weed free through postemergence application of glyphosate and glufosinate and the objectives were to determine soybean tolerance. Two soybean varieties were evaluated. Preemergence herbicide treatments were applied on June 4 (see Table 1 for herbicide treatments and Table 3 for a description of application). In the week following application there was 0.2 inches of rainfall. Weed control was evaluated 37 and 57 days after treatment (DAT). Control of kochia, wild buckwheat, common lambsquarters, and common mallow were greatest (87 to 90%, 57 DAT, with the tank mix of metribuzin at 10.7 oz/A and sulfentrazone at 8 oz/A. Metribuzin alone resulted in 72 to 82% control of these weeds at 57 DAT. Sulfentrazone alone resulted in 72 to 92% control of these weeds. Kochia control was similar (81 to 92%) for all combinations of metribuzin and sulfentrazone as well as the 8oz/A rate of sulfentrazone (83%). Kochia control with metribuzin alone (73 to 75%) and sulfentrazone at the 4 oz/A rate (75%) was less than the tank-mixes of these herbicides.

Lead Author

Lead Author:

Caleb Dalley

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Availability:

Web only

Publication Sections

Table 1. Evaluation of fall application of metribuzin and pyroxasulfone for weed control in peas.

			Kochia				Wild buckwheat				Common lambsquarters				Common Mallow
Treatment^a		Rate	37 DAT		57 DAT		37 DAT		57 DAT		37 DAT		57 DAT		37 DAT		57 DAT
		oz/A	–––––––––––––––––––––––––––– % control –––––––––––––––––––––––––––––––
1	Untreated		0	e	0	c	0	e	0	e	0	d	0	e	0	f	0	d
2	Metribuzin	5.3	85	bc	73	b	78	d	70	d	75	c	70	d	75	e	67	c
3	Metribuzin	10.7	75	cd	75	b	76	d	76	c	84	b	82	c	81	cd	80	b
4	Spartan	4	69	d	75	b	82	c	82	b	98	a	86	bc	79	d	72	c
5	Spartan	8	93	ab	83	ab	85	bc	88	a	96	a	92	a	84	c	80	b
6	Metribuzin	5.3	90	ab	81	ab	83	bc	84	b	92	a	86	bc	83	c	77	b
	Spartan	4
7	Metribuzin	10.7	98	ab	92	a	86	b	84	b	97	a	89	ab	87	b	81	b
	Spartan	4
8	Metribuzin	5.3	94	ab	91	a	87	ab	89	a	98	a	94	a	87	b	82	ab
	Spartan	8
9	Metribuzin	10.7	99	a	92	a	90	a	92	a	95	a	92	a	90	a	87	a
	Spartan	8
LSD P=.05			8.9		9.4		3.9		3.9		6.8		5.3		2.5		4.8
Standard Deviation			6.7		6.9		3.2		3.2		5.6		4.4		2.1		4.0
CV			9.61		10.97		4.38		4.34		6.88		5.76		2.83		5.72
Treatment F			72.121		55.169		300.992		316.772		125.942		180.136		719.954		180.457
Treatment Prob(F)			0.0001		0.0001		0.0001		0.0001		0.0001		0.0001		0.0001		0.0001

There were no differences in stand count (19 DAT) or soybean height (51 DAT) in either soybean variety. Soybean yield in the weedy trial was greatest in treatments where weed control was highest (combinations of metribuzin and sulfentrazone). Soybean yield in the untreated control was reduced by more than 50%. In the weed free trial, soybean yield following herbicide treatments was equal to or greater than yield in the weed free control. This trial showed that soybean were tolerant to metribuzin and sulfentrazone rates that were applied. The soil at this location is a silty clay loam with greater than 3% organic matter and a pH of around 5.6. Soybean tolerance to metribuzin can be influenced by soil conditions, with higher injury potential to soybean in sandy soils, or soils with high pH and low organic matter.

Table 2. Evaluation of fall application of metribuzin and pyroxasulfone for crop response in peas.

											Soybean yield
			Stand count				Soybean height				Weedy				Weed free
Treatment^a		Rate	AG07XF2		AG07XF4		AG07XF2		AG07XF4		AG07XF2		AG07XF4		AG07XF2		AG07XF4
		oz/A	Plants/A				IN				BU/A
1	Weed Free		100264	-	108232	-	12	-	11	-	13.8	f	12.9	f	27.2	-	24.8	cd
2	Metribuzin	5.3	101592	-	108232	-	12	-	11	-	18.1	e	17.6	e	27.8	-	28.6	ab
3	Metribuzin	10.7	101592	-	114872	-	12	-	11	-	21.1	cde	21.9	cd	31.6	-	27.0	bc
4	Spartan	4	105576	-	112216	-	13	-	12	-	19.4	de	20.5	de	28.0	-	27.3	abc
5	Spartan	8	108896	-	110224	-	13	-	11	-	22.8	c	22.0	cd	27.1	-	30.6	a
6	Metribuzin	5.3	100928	-	107568	-	12	-	11	-	21.7	cd	25.3	bc	27.4	-	21.6	d
	Spartan	4
7	Metribuzin	10.7	106240	-	110224	-	12	-	12	-	23.7	bc	22.2	cd	33.0	-	24.4	cd
	Spartan	4
8	Metribuzin	5.3	95616	-	103584	-	12	-	11	-	26.5	ab	30.4	a	26.7	-	24.7	cd
	Spartan	8
9	Metribuzin	10.7	97608	-	109560	-	13	-	12	-	27.4	a	29.2	ab	30.4	-	24.6	cd
	Spartan	8
LSD P=.05			9978.2		9879.5		0.9		0.8		3.14		4.12		4.95		3.55
Standard Deviation			8247.9		8166.4		0.8		0.7		2.60		3.41		4.09		2.94
CV			8.08		7.46		6.17		5.69		12.0		15.2		14.22		11.32
Treatment F			1.050		0.594		1.186		0.973		10.522		10.161		1.252		3.339
Treatment Prob(F)			0.4284		0.7736		0.3479		0.4797		0.0001		0.0001		0.3132		0.0104

Application Description		Application equipment
Date	Jun-4-2025	Equipment Type	Tractor mounted
Start, Stop Time	2:39, 3:05 PM	Operation Pressure	42 PSI
Air Temperature Start, Stop	71.1, 66.4 F	Nozzle Model	11002DG
% Relative Humidity Start, Stop	32.2, 40.2	Nozzle Spacing	20 IN
Wind Velocity+Dir. Start	1.7 MPH, SSW	Boom Height	22.0 IN
Wind Velocity+Dir. Max	12.7 MPH, WNW	Ground Speed	4 MPH
Soil Temperature	57 F	Carrier	WATER
% Cloud Cover	10	Application Amount	10 GAL/AC

Weed control and soybean response to preemergence application of metribuzin and sulfentrazone at Hettinger, ND, 2025.

Table 1. Evaluation of fall application of metribuzin and pyroxasulfone for weed control in peas.

Table 2. Evaluation of fall application of metribuzin and pyroxasulfone for crop response in peas.

Table 3. Application environment and equipment for preemergence herbicide application in soybean.

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