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Fall Weed Control In Wheat And Barley

Oct 16, 2014

Remember to keep weeds in check this fall in your small grains.

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, 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, Glory and others are applied in the fall, their recrop restrictions still prevent seeding 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

    

Herbicide

Crops

Strengths

Growth stage

Remarks, if any

2,4-D

Wheat, barley, rye

Horseweed, mustards, dandelion

3–6

 

Axial XL

Wheat, barley

Annual/Italian ryegrass

2–8

No control of ACCase-resistant species

Banvel/Clarity

Wheat, barley

Horseweed, thistles

3–6

 

Glory

Wheat, barley

ALS-resistant chickweed,

1–4

Controls winter annual broadleaves

Harmony Extra

Wheat, barley

Most broadleaves, garlic

1–7

Will not control ALS-resistant chickweed

Huskie

Wheat, barley, triticale

Most broadleaves

1–7

Has some activity on marestail/horseweed

MCPA

Wheat, barley, rye

Same as 2,4-D

3–6

 

Buctril

Wheat, barley, rye

Mustards

1–9

 

Peak

Wheat, barley, rye, triticale

Mustards, garlic

2–6

Watch recrop restrictions

PowerFlex HL

Wheat

Downy brome, cheat, annual/Italian ryegrass

 

Controls some broadleaves; will not control ALS-resistant chickweed

Starane Ultra

Wheat, barley

Chickweed (including ALS-resistant)

2–9

 

Stinger

Wheat, barley

Thistles

2–9

Watch recrop restrictions

Osprey

Wheat

Annual/Italian ryegrass, annual bluegrass

1–5

Controls some broadleaves

Maverick

Wheat

Downy brome, cheat, chess

1–5

Controls some broadleaves, watch recrop restrictions

Source : psu.edu