Fall Weed Control in Wheat and Barley

As fall weeds compete with wheat and barley establishment, below are some herbicide options to consider.
Fall Weed Control in Wheat and Barley - Articles

Updated: October 16, 2018

Fall Weed Control in Wheat and Barley

Mary Burrows, Montana State University, Bugwood.org

Dense populations of winter annual weeds can compete with wheat and barley in late fall and early spring and slow the rate of crop development potentially reducing yield. If winter annual weeds like common chickweed, henbit, marestail, winter annual grasses, and others emerge with the small grain and are left unchecked, the potential impact on yield could be great. In these situations, it may make sense to kill these weeds in the fall rather than early spring. Harmony Extra is the most broad spectrum herbicide for broadleaf control, but resistant populations of common chickweed are becoming evident in parts of the state. In addition, there are several herbicides labeled for grass control in wheat and fall is typically the best time to make an application. Make sure to include the necessary spray adjuvants. Remember that cool (less than 50°F) cloudy days can reduce herbicide activity. Also, if you plan to frost-seed or drill a companion crop such as red clover in early spring it may be best to make a fall herbicide application to avoid certain issues with herbicide residuals affecting their establishment. However, even if products such as PowerFlex HL, Osprey, Dimetric, and others are applied in the fall, their recrop restrictions still prevent seeding of certain crops next spring. The following table summarizes some fall herbicide options for small grains. Check a current herbicide label for the latest use information.

Common Fall Herbicide Options for Small Grains

HerbicideCropsStrengthsGrowth stageRemarks, if any
2,4-DWheat, barley, rye, oatsMarestail, mustards, dandelion3–6
AimWheat, barley, oatsStar-of-Bethlehem, speedwell1–5
Anthem FlexWheatAnnual grasses and broadleavesdelayed pre to early post (1-3)Does not control emerged weeds; suppression only of chickweed and marestail
Axial XLWheat, barleyAnnual/Italian ryegrass2–8No control of ACCase-resistant species
Axiomwheat, triticaleCertain annual grasses and several broadleaves

spike-1 (2-leaf)

Clarity/BanvelWheat, barleyMarestail, thistles3–6
Dimetric EXTWheat, barleyALS-resistant chickweed1–4Controls other winter annual broadleaves
Harmony ExtraWheat, barley, oatsMost broadleaves, garlic1–7Will not control ALS-resistant chickweed
HuskieWheat, barley, triticaleMost broadleaves1–7Has good activity on marestail
Maestro (Buctril)Wheat, barley, ryeMustards1–9
MCPAWheat, barley, ryeSame as 2,4-D

3–6

OspreyWheat, triticaleAnnual/Italian ryegrass, annual bluegrass1–5Controls some broadleaves
PeakWheat, barley, oats, rye, triticaleMustards, garlic2–6Watch recrop restrictions
PowerFlex HLWheat, triticaleDowny brome, cheat, annual/Italian ryegrass

3-leaf to 6

Controls some broadleaves; will not control ALS-resistant chickweed
Prowl H20Wheat, triticaleAnnual ryegrass, downy brome, some annual broadleaves1–7Apply after small grain emergence but before weeds have emerged
QuelexWheat, barley, triticaleAnnual broadleaves2–8Watch recrop restrictions
SharpenWheat, barley, oats, rye, triticaleAnnual broadleavesbefore crop emergenceControls existing marestail
Starane UltraWheat, barleyChickweed (including ALS-resistant)2–9
StingerWheat, barley, oatsThistles2–9Watch recrop restrictions
TalinorWheat, barleyAnnual broadleaves2–9Watch recrop restrictions
Valor SX or EZ

Wheat

Annual broadleaves7-days early preplantImproves marestail control; plant wheat at least 1" deep
ZiduaWheatAnnual grasses and broadleavesdelayed pre to early post (4 tillers)Does not control emerged weeds; suppression only of chickweed and marestail

Authors

William S. Curran, Ph.D.