Italian ryegrass infestation in winter wheat. Photo compliments of Virginia Tech.
Over the last few years, several residual herbicides are now labeled for weed control in wheat and sometimes barley. These herbicides are labeled either preplant or perhaps early postemergence and can target special weed problems such as winter annual grasses or problematic broadleaves. Table 1 is a brief summary of what’s available for this type of application. For the full list of available herbicides and their comments, see Table 2.5-7 in the Penn State Agronomy Guide or Table 5-7 in the Mid-Atlantic Field Crop Weed Management Guide and for effectiveness ratings of fall planted small grain herbicides on winter annuals see Tables 2.5.5 or 5.5 in the same Guides.
Table 1. Comments on a select number of herbicides for small grains.
Site of Action Number
Axiom 68 DF
spiking to 2 leaf (growth stage 1)
- For use on wheat and triticale.
- Strengths - Annual/Italian ryegrass
- Plant seeds 1 to 2 inches deep to improve crop safety; do not use on broadcast-seeded wheat.
- Apply when crop is between full germination and 2-leaf stage and when weeds have not germinated (preemergence) and 1-leaf stage. Apply prior to weed emergence to 1-leaf-stage weeds.
- Use rate depends on soil texture; see product label.
- Some crop varieties are more sensitive; see product label.
- No rotation restriction to soybean; 12-month rotation restriction to vegetables; see Table 1-5.
- Water quality advisory.Water quality advisory.
Prowl H2O 3.8SC
first-leaf to before the flag leaf is visible (growth stages 1–7)
- For use on wheat or triticale only.
- Strengths - Annual ryegrass, downy brome, some annual broadleaves
- Wheat or triticale must be planted 0.5–1 inch deep to avoid crop injury.
- Must be applied before weed emergence. Any emerged weeds will not be controlled, so use a tank mixture to control them.
- For best results, apply Prowl H2O once the wheat rows are visible and before weeds have emerged.
- Prowl controls many annual grass and broadleaf weeds.
- No rotation restriction to soybean or vegetables; see Table 1-5.
preplant or preemergence
1–4 fl oz
- For use on wheat, barley, oats, rye, and triticale.
- Strengths – annual broadleaves
- Be sure seed row is sufficiently covered with soil to avoid washing and concentrating the herbicide in the seed zone.
- Apply Sharpen for burndown and/or limited residual control of certain annual broadleaf weeds; see Table 5-3.
- Sharpen does not control grass weeds.
- Do not apply Sharpen if crop has emerged.
- No rotation restriction to soybean; 1 to 5 months for vegetables, depending on species; see Table 1-5.
Valor SX 51WDG
- For use on wheat only in DE, MD, NJ, PA, and VA.
- Strengths – annual broadleaves
- Must be applied 7 days prior to planting in no-till or minimum-till wheat; 30-day preplant restriction from conventionally tilled wheat.
- When using as a burndown, apply 2 oz/A.
- Wheat must be planted a minimum of 1 inch deep.
- Valor improves control of horseweed and other broadleaf weeds when tank-mixed with other herbicides that broaden control spectrum.
- With sandy soils, stunting and stand loss can occur if seed is not planted at least 1 inch deep and heavy rain occurs shortly after application.
- No rotation restriction to soybean; more than 4 months for vegetables; see Table 1-5.
delayed pre- to early postemergence (4th tiller)
1.25-2.5 fl oz
Anthem Flex 4SE
2-4.5 fl oz
- For use on wheat only.
- Strengths – annual grasses and broadleaves
- All products can be applied as a delayed preemergence (80% germination with 0.5-inch-long shoot to spiking) to control annual grasses and small-seeded broadleaf weeds.
- Do not use on broadcast seeded wheat; do not plant wheat deeper than 1.5 inches (but at least 1 one inch deep).
- Do not apply if more than 0.25 inches of rain is expected within 48 hours.
- Crop injury may result under prolonged wet soil conditions.
- Consult label as soil texture influences rate.
- Zidua alone will not control emerged weeds; Anthem Flex contains carfentrazone (Aim) which will provide control of certain weed species if they are very small at time of application.
- No rotation restriction to soybean; 18 months for vegetables; see Table 1-5.
- Water quality advisory.