Title

Evaluation of herbicide options for postemergence weed control in spring wheat at Hettinger, ND, 2024

(Research Report, Hettinger REC, December 2024)

File

Publication File:

Summary

A trial was conducted at Hettinger, ND in 2024 to evaluate the efficacy of herbicides for weed control in spring wheat. The primary focus of this trial was to evaluate kochia control, although we were also able to evaluate wild buckwheat, common lambsquarters, and common mallow. For years, the herbicide fluroxypyr has been instrumental for controlling kochia in spring wheat. In recent years, there has been development of some populations of kochia that have increased tolerance to fluroxypyr, which has necessitated changes in strategies for controlling this weed. Most of the herbicide treatments in this trial contain fluroxypyr as a lone treatment or as premixes or tank-mixes (Table 1). Spring wheat was planted on May 1, 2024, using a no-till drill at a depth of 2 inches. Spring wheat emerged on May 14. Herbicide treatments were applied on June 7 when weeds averaged 2 to 3 inches in height (Table 2). When evaluated 2 weeks after treatment (2 WAT), fluroxypyr alone (Starane Ultra) controlled kochia at 72%, with lesser control of other weeds. The addition of bromoxynil (Maestro 2EC) to fluroxypyr increased kochia control to 81% for 16 oz/A of Maestro 2EC, and 92% for both 24 and 32 oz/A of Maestro 2EC. All other treatments controlled kochia at 84 to 93%. Wild buckwheat control increased with combinations of fluroxypyr and bromoxynil, with the best treatments being, Starane Ultra plus Maestro (24 and 32 oz/A) and Bison (MCPA plus bromoxynil) plus Starane Ultra (2.8 and 5.6 oz/A). Common lambsquarters and common mallow control followed a similar trend with control increasing with higher amounts of bromoxynil added to fluroxypyr. Little to no injury was observed with any of these treatments. Wheat yield was lowest in the untreated control, with most treatments being statistically similar. This trial demonstrates the importance of not relying on a single herbicide or mode of action when trying to control weed in spring wheat (or any crop).

Lead Author

Lead Author:

Caleb Dalley

Availability

Availability:

Web only

Publication Sections

Table 1. Evaluation of postemergence options for weed control in spring wheat at Hettinger, ND, 2024.

											––––––Spring wheat–––––
Treatment		Rate	Kochia		wild buckwheat		lambsquarters		mallow		Injury		Yield
		oz/A	–––––––––– % control –––––––––––––								Bu/A		LB/BU
1	Untreated		0	d	0	f	0	d	0	e	0	h	36.1	b
2	Starane Ultra	5.6	72	c	60	e	41	c	55	d	1	gh	38.5	ab
3	Starane Ultra	5.6	81	bc	82	cd	83	b	69	bc	6	bcd	38.0	ab
	Maestro 2EC	16
4	Starane Ultra	5.6	92	a	88	ab	95	ab	75	ab	8	ab	37.6	ab
	Maestro 2EC	24
5	Starane Ultra	5.6	92	a	92	a	96	ab	82	a	9	a	37.5	ab
	Maestro 2EC	32
6	Huskie FX	13.5	88	ab	82	cd	91	ab	77	ab	4	def	40.4	a
7	Huskie Complete	13.7	88	ab	81	cd	92	ab	80	ab	3	efg	39.9	ab
8	Batalium Amped	16	88	ab	86	bc	84	ab	82	ab	5	c-f	38.7	ab
9	Talinor	13.7	84	ab	81	cd	92	ab	61	cd	3	fg	41.4	a
10	Tolvera	11	85	ab	79	d	92	ab	77	ab	4	def	35.9	b
11	Carnivore	16	86	ab	85	bc	88	ab	74	ab	8	abc	38.4	ab
12	Carnivore	24	90	ab	83	bcd	89	ab	72	abc	7	abc	38.5	ab
13	Bison	24	85	ab	84	bcd	92	ab	79	ab	6	b-e	39.0	ab
14	Bison	24	93	a	88	ab	91	ab	80	ab	7	abc	38.9	ab
	Starane Ultra	2.8
15	Bison	24	90	ab	88	ab	97	a	81	ab	8	ab	39.0	ab
	Starane Ultra	5.6
LSD P=.05			9.1		6.0		12.9		11.3		2.6		3.70
Standard Deviation			6.4		4.2		9.0		7.9		1.8		2.58
CV			7.9		5.42		11.42		11.45		32.6		7.09
Treatment F			52.358		116.292		32.962		27.195		10.418		2.615
Treatment Prob(F)			0.0001		0.0001		0.0001		0.0001		0.0001		0.0106

Table 2. Application environment and equipment for postemergence application of herbicide treatments for weed control in spring wheat.

Application Description		Application equipment
Date	Jun-7-2024	Equipment Type	Tractor mounted
Start Time	8:19 AM	Operation Pressure	42 PSI
Stop Time	9:18 AM	Nozzle Model	11002DG
Air Temperature Start, Stop	67.7, 66.7 F	Nozzle Spacing	20 IN
% Relative Humidity Start, Stop	42.5, 36.9	Boom Length	100 IN
Wind Velocity+Dir. Start	4.1 MPH, SSE	Boom Height	20 IN
Wind Velocity+Dir. Stop	9.9 MPH, SSE	Ground Speed	4.2 MPH
Wind Velocity+Dir. Max	12.1 MPH, SSE	Carrier	WATER
Wet Leaves (Y/N)	N, no	Application Amount	10 GAL/AC
Soil Temperature	46 F	Propellant	CO2
% Cloud Cover	25	Tank Mix (Y/N)	Yes

Evaluation of herbicide options for postemergence weed control in spring wheat at Hettinger, ND, 2024

Table 1. Evaluation of postemergence options for weed control in spring wheat at Hettinger, ND, 2024.

Table 2. Application environment and equipment for postemergence application of herbicide treatments for weed control in spring wheat.

This is the prefooter section