Common corn herbicides and potential to injure early/interseeded cover crops.

Grass Icon - GreenGrass Cover Crops

Injury Likely

Active ingredient: atrazine

Normal Rate/acre Half life (days) Cash crop restrictions Other
1 – 2 qt 60 Can plant corn, sorghum, and soybean the following year (some products allow others) More persistent in high pH soils (>7). Rates <1 lb/acre can allow more flexibility

Active ingredient: nicosulfuron / nicosulfuron + rimsulfuron

Normal Rate/acre Half life (days) Cash crop restrictions Other
0.66 oz / 0.75 oz 21 Sensitive crops have 10 – 18 month restriction More persistent in high pH soils (>7)

Active ingredient: pyroxasulfone

Normal Rate/acre Half life (days) Cash crop restrictions Other
0.16 (lbm/ac) 16 – 26 Cotton, maize, mung beans, sorghum, soybeans and sunflowers have 5 month restriction.

Active ingredient: simazine

Normal Rate/acre Half life (days) Cash crop restrictions Other
1 – 2 qt 60 Can plant corn, sorghum, and soybean the following year (some products allow others) Soil pH > 7

Active ingredient: metolachlor

Normal Rate/acre Half life (days) Cash crop restrictions Other
1.67 pt 15 – 50 Labeled for use on many crops Higher rates and later applications more of a potential problem

Active ingredient: tembotrione + thiencarbazone

Normal Rate/acre Half life (days) Cash crop restrictions Other
3 fl. oz 15 Four mo. for wheat, 10 mo. for barley, sorghum, oats and alfalfa 15 inches of cumulative precipitation required from application to planting rotation crops except wheat

Active ingredient: topromesone

Normal Rate/acre Half life (days) Cash crop restrictions Other
0.75 fl. oz 14 Alfalfa, canola, soybean and sunflower have a 9 mo. restriction

Injury Possible

Active ingredient: acetochlor

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
2 pt 10 – 20 Four mo. for wheat and 9 mo. for alfalfa and clovers Most crops should be fine Food or feed residues rather than crop injury may be a concern Nonfood / feed winter cover crops are allowed after corn harvest

Active ingredient: atrazine

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1 – 2 qt 60 Can plant corn, sorghum, and soybean the following year (some products allow others) Sorghum species Cereals, ryegrass, legumes, and mustards More persistent in high pH soils (>7). Rates <1 lb/acre can allow more flexibility

Active ingredient: dimethenamid

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
16 fl. oz 20 Four mo. for cereal grains and anything the following spring Most crops should be fine Food or feed residues rather than crop injury may be a concern Nonfood / feed winter cover crops should be OK after corn harvest

Active ingredient: isoxaflutole

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz

6 fl. oz

50 – 120 Small seeded leg umes and vegetables have a 10 to 18 month restriction Fall cereal grains Cereals, Ryegrass, legumes, and mustards 15 inches of cumulative precipitation required from application to planting rotation crops except soybean, barely, weat, sorghum, and sunflower

Active ingredient: isoxaflutole + thiencarbazone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
5.6 fl. oz 50 – 120 Four mo. for wheat, 9 mo. for barley and 17 mo. for alfalfa, oats, soghum, and canola Wheat, triticale, rye Small seeded legumes, mustards, sorghum 15 to 30 inches of cumulative precipitation from application to planting for sensitive crops

Active ingredient: metribuzin

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
0.33 lb 14 – 60 Recrop restrictions range from 4 to 12 mo. Cereal grains and ryegrass Slight risk for small seeded legumes and mustards Nonfood / feed winter cover crops allowed

Active ingredient: pendamethalin

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 pt 44 Wheat and barley after 4 mo. Other rotational crops the following year. Cereal grains Small seeded legumes and annual ryegrass Nonfood / feed winter cover crops should be OK

Injury Unlikely

Active ingredient: clopyralid

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
5 oz 40 Recrop intervals 10.5 to 18 mo. for legumes All grasses Small seeded legumes

Active ingredient: dicamba

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
16 to 24 fl. oz 5 – 14 15 days per 8 fl. oz/acre for small grains All crops Only at high rates or less than 120 days after application Anything can be planted after 120 days with 24 fl. oz/acre or less

Active ingredient: flumetsulam

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1 oz 14 – 120 Cash crop restrictions from 4 mo. for alfalfa and cereals to 26 mo. for canola Cereal grains Small seeded legumes, mustards, and annual ryegrass Cover crops and forage grasses are restricted for 9 mo.

Active ingredient: halosulfuron

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
2 / 3 oz 9 – 27 Nine mo. for alfalfa, clovers, soybean and 15 mo. for canola Cereal grains and sorghum after 2 mo. and other grasses Small seeded legumes, mustards Halosulfuron also an ingredient in Yukon

Active ingredient: mesotrione

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 – 6 fl. oz 5 – 32 10 to 18 months for legumes and vegetables All grasses Small seeded legumes, mustards Sequential applications (PRE fb POST) increase the potential for injury

Active ingredient: rimsulfuron

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
2 oz 2 – 4 Winter cereals have a 3 mo. restriction and many crops are restricted for 10 mo. Based on the short half-life, most fall cover crops should be OK in PA None More persistent in drought conditions

Active ingredient: saflufenacil

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz 7 – 35 Any crop can be planted 4 mo. after application All None This product has been reported more persistent in western Canada

Legume Icon - RedLegume Cover Crops

Injury Likely

Active ingredient: atrazine

Normal Rate/acre Half life (days) Cash crop restrictions Other
1 – 2 qt 60 Can plant corn, sorghum, and soybean the following year (some products allow others) More persistent in high pH soils (>7). Rates <1 lb/acre can allow more flexibility

Active ingredient: clopyralid

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
5 oz 40 Recrop intervals 10.5 to 18 mo. for legumes All grasses Small seeded legumes

Active ingredient: flumetsulam

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1 oz 14 – 120 Cash crop restrictions from 4 mo. for alfalfa and cereals to 26 mo. for canola Cereal grains Small seeded legumes, mustards, and annual ryegrass Cover crops and forage grasses are restricted for 9 mo.

Active ingredient: halosulfuron

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
2 / 3 oz 9 – 27 Nine mo. for alfalfa, clovers, soybean and 15 mo. for canola Cereal grains and sorghum after 2 mo. and other grasses Small seeded legumes, mustards Halosulfuron also an ingredient in Yukon

Active ingredient: isoxaflutole + thiencarbazone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
5.6 fl. oz 50 – 120 Four mo. for wheat, 9 mo. for barley and 17 mo. for alfalfa, oats, soghum, and canola Wheat, triticale, rye Small seeded legumes, mustards, sorghum 15 to 30 inches of cumulative precipitation from application to planting for sensitive crops

Active ingredient: isoxaflutole

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz

6 fl. oz

50 – 120 Small seeded leg umes and vegetables have a 10 to 18 month restriction Fall cereal grains Cereals, Ryegrass, legumes, and mustards 15 inches of cumulative precipitation required from application to planting rotation crops except soybean, barely, weat, sorghum, and sunflower

Active ingredient: mesotrione

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 – 6 fl. oz 5 – 32 10 to 18 months for legumes and vegetables All grasses Small seeded legumes, mustards Sequential applications (PRE fb POST) increase the potential for injury

Active ingredient: pyroxasulfone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
0.133 20 4 mo. for wheat, 11 mo. for other small grains, and 10 mo. for alfalfa Most crops should be fine Food or feed residues rather than crop injury may be a concern Nonfood / feed winter cover crops should be OK after corn harvest

Active ingredient: simazine

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1 – 2 qt 60 Can plant corn, sorghum, and soybean the following year (some products allow others) Sorghum species Cereals, Ryegrass, legumes, and mustards Soil pH > 7

Active ingredient: tembotrione + thiencarbazone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz 15 Four mo. for wheat, 10 mo. for barley, sorghum, oats and alfalfa Wheat, triticale, rye Small seeded legumes, mustards, sorghum 15 inches of cumulative precipitation required from application to planting rotation crops except wheat

Active ingredient: topromesone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
0.75 fl. oz 14 Alfalfa, canola, soybean and sunflower have a 9 mo. restriction Wheat, barley, oats, and rye are allowed after 3 mo. Ryegrass should also be OK Although many broadleaves are restricted, Impact does not have much soil activity

Injury Possible

Active ingredient: acetochlor

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
2 pt 10 – 20 Four mo. for wheat and 9 mo. for alfalfa and clovers Most crops should be fine Food or feed residues rather than crop injury may be a concern Nonfood / feed winter cover crops are allowed after corn harvest

Active ingredient: atrazine

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1 – 2 qt 60 Can plant corn, sorghum, and soybean the following year (some products allow others) Sorghum species Cereals, ryegrass, legumes, and mustards More persistent in high pH soils (>7). Rates <1 lb/acre can allow more flexibility

Active ingredient: dicamba

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
16 to 24 fl. oz 5 – 14 15 days per 8 fl. oz/acre for small grains All crops Only at high rates or less than 120 days after application Anything can be planted after 120 days with 24 fl. oz/acre or less

Active ingredient: dimethenamid

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
16 fl. oz 20 Four mo. for cereal grains and anything the following spring Most crops should be fine Food or feed residues rather than crop injury may be a concern Nonfood / feed winter cover crops should be OK after corn harvest

Active ingredient: metribuzin

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
0.33 lb 14 – 60 Recrop restrictions range from 4 to 12 mo. Cereal grains and ryegrass Slight risk for small seeded legumes and mustards Nonfood / feed winter cover crops allowed

Active ingredient: pendamethalin

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 pt 44 Wheat and barley after 4 mo. Other rotational crops the following year. Cereal grains Small seeded legumes and annual ryegrass Nonfood / feed winter cover crops should be OK

Active ingredient: metolachlor

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1.67 pt 15 – 50 Labeled for use on many crops Almost anything Annual ryegrass or other small seeded grasses Higher rates and later applications more of a potential problem

Injury Unlikely

Active ingredient: rimsulfuron

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
2 oz 2 – 4 Winter cereals have a 3 mo. restriction and many crops are restricted for 10 mo. Based on the short half-life, most fall cover crops should be OK in PA None More persistent in drought conditions

Active ingredient: saflufenacil

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz 7 – 35 Any crop can be planted 4 mo. after application All None This product has been reported more persistent in western Canada

Broadleaf Icon - BlueBroadleaf Cover Crops

Injury Likely

Active ingredient: atrazine

Normal Rate/acre Half life (days) Cash crop restrictions Other
1 – 2 qt 60 Can plant corn, sorghum, and soybean the following year (some products allow others) More persistent in high pH soils (>7). Rates <1 lb/acre can allow more flexibility

Active ingredient: flumetsulam

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1 oz 14 – 120 Cash crop restrictions from 4 mo. for alfalfa and cereals to 26 mo. for canola Cereal grains Small seeded legumes, mustards, and annual ryegrass Cover crops and forage grasses are restricted for 9 mo.

Active ingredient: halosulfuron

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
2 / 3 oz 9 – 27 Nine mo. for alfalfa, clovers, soybean and 15 mo. for canola Cereal grains and sorghum after 2 mo. and other grasses Small seeded legumes, mustards Halosulfuron also an ingredient in Yukon

Active ingredient: isoxaflutole

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz

6 fl. oz

50 – 120 Small seeded leg umes and vegetables have a 10 to 18 month restriction Fall cereal grains Cereals, Ryegrass, legumes, and mustards 15 inches of cumulative precipitation required from application to planting rotation crops except soybean, barely, weat, sorghum, and sunflower

Active ingredient: isoxaflutole + thiencarbazone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
5.6 fl. oz 50 – 120 Four mo. for wheat, 9 mo. for barley and 17 mo. for alfalfa, oats, soghum, and canola Wheat, triticale, rye Small seeded legumes, mustards, sorghum 15 to 30 inches of cumulative precipitation from application to planting for sensitive crops

Active ingredient: mesotrione

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 – 6 fl. oz 5 – 32 10 to 18 months for legumes and vegetables All grasses Small seeded legumes, mustards Sequential applications (PRE fb POST) increase the potential for injury

Active ingredient: simazine

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1 – 2 qt 60 Can plant corn, sorghum, and soybean the following year (some products allow others) Sorghum species Cereals, Ryegrass, legumes, and mustards Soil pH > 7

Injury Possible

Active ingredient: atrazine

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1 – 2 qt 60 Can plant corn, sorghum, and soybean the following year (some products allow others) Sorghum species Cereals, ryegrass, legumes, and mustards More persistent in high pH soils (>7). Rates <1 lb/acre can allow more flexibility

Active ingredient: metribuzin

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
0.33 lb 14 – 60 Recrop restrictions range from 4 to 12 mo. Cereal grains and ryegrass Slight risk for small seeded legumes and mustards Nonfood / feed winter cover crops allowed

Active ingredient: pendamethalin

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 pt 44 Wheat and barley after 4 mo. Other rotational crops the following year. Cereal grains Small seeded legumes and annual ryegrass Nonfood / feed winter cover crops should be OK

Active ingredient: pyroxasulfone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
0.133 20 4 mo. for wheat, 11 mo. for other small grains, and 10 mo. for alfalfa Most crops should be fine Food or feed residues rather than crop injury may be a concern Nonfood / feed winter cover crops should be OK after corn harvest

Active ingredient: tembotrione + thiencarbazone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz 15 Four mo. for wheat, 10 mo. for barley, sorghum, oats and alfalfa Wheat, triticale, rye Small seeded legumes, mustards, sorghum 15 inches of cumulative precipitation required from application to planting rotation crops except wheat

Active ingredient: tembotrione

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz 14 Four mo. for cereal grains, 10 mo. for sorghum, canola, and alfalfa Cereal grains after 4 mo. Unknown – Small seeded legumes, mustards could be a problem Other crops may be seeded after a successful field bioassay.

Active ingredient: topromesone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
0.75 fl. oz 14 Alfalfa, canola, soybean and sunflower have a 9 mo. restriction Wheat, barley, oats, and rye are allowed after 3 mo. Ryegrass should also be OK Although many broadleaves are restricted, Impact does not have much soil activity

Injury Unlikely

Active ingredient: acetochlor

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
2 pt 10 – 20 Four mo. for wheat and 9 mo. for alfalfa and clovers Most crops should be fine Food or feed residues rather than crop injury may be a concern Nonfood / feed winter cover crops are allowed after corn harvest

Active ingredient: clopyralid

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
5 oz 40 Recrop intervals 10.5 to 18 mo. for legumes All grasses Small seeded legumes

Active ingredient: dimethenamid

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
16 fl. oz 20 Four mo. for cereal grains and anything the following spring Most crops should be fine Food or feed residues rather than crop injury may be a concern Nonfood / feed winter cover crops should be OK after corn harvest

Active ingredient: dicamba

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
16 to 24 fl. oz 5 – 14 15 days per 8 fl. oz/acre for small grains All crops Only at high rates or less than 120 days after application Anything can be planted after 120 days with 24 fl. oz/acre or less

Active ingredient: pendamethalin

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 pt 44 Wheat and barley after 4 mo. Other rotational crops the following year. Cereal grains Small seeded legumes and annual ryegrass Nonfood / feed winter cover crops should be OK

Active ingredient: rimsulfuron

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
2 oz 2 – 4 Winter cereals have a 3 mo. restriction and many crops are restricted for 10 mo. Based on the short half-life, most fall cover crops should be OK in PA None More persistent in drought conditions

Active ingredient: saflufenacil

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz 7 – 35 Any crop can be planted 4 mo. after application All None This product has been reported more persistent in western Canada

Active ingredient: metolachlor

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1.67 pt 15 – 50 Labeled for use on many crops Almost anything Annual ryegrass or other small seeded grasses Higher rates and later applications more of a potential problem

Grass Icon - GreenLegume Icon - RedBroadleaf Icon - BlueGrass / Legume / Broadleaf Mixtures

Injury Likely

Active ingredient: atrazine

Normal Rate/acre Half life (days) Cash crop restrictions Other
1 – 2 qt 60 Can plant corn, sorghum, and soybean the following year (some products allow others) More persistent in high pH soils (>7). Rates <1 lb/acre can allow more flexibility

Active ingredient: clopyralid

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
5 oz 40 Recrop intervals 10.5 to 18 mo. for legumes All grasses Small seeded legumes

Active ingredient: flumetsulam

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1 oz 14 – 120 Cash crop restrictions from 4 mo. for alfalfa and cereals to 26 mo. for canola Cereal grains Small seeded legumes, mustards, and annual ryegrass Cover crops and forage grasses are restricted for 9 mo.

Active ingredient: halosulfuron

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
2 / 3 oz 9 – 27 Nine mo. for alfalfa, clovers, soybean and 15 mo. for canola Cereal grains and sorghum after 2 mo. and other grasses Small seeded legumes, mustards Halosulfuron also an ingredient in Yukon

Active ingredient: isoxaflutole + thiencarbazone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
5.6 fl. oz 50 – 120 Four mo. for wheat, 9 mo. for barley and 17 mo. for alfalfa, oats, soghum, and canola Wheat, triticale, rye Small seeded legumes, mustards, sorghum 15 to 30 inches of cumulative precipitation from application to planting for sensitive crops

Active ingredient: isoxaflutole

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz

6 fl. oz

50 – 120 Small seeded leg umes and vegetables have a 10 to 18 month restriction Fall cereal grains Cereals, Ryegrass, legumes, and mustards 15 inches of cumulative precipitation required from application to planting rotation crops except soybean, barely, weat, sorghum, and sunflower

Active ingredient: mesotrione

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 – 6 fl. oz 5 – 32 10 to 18 months for legumes and vegetables All grasses Small seeded legumes, mustards Sequential applications (PRE fb POST) increase the potential for injury

Active ingredient: nicosulfuron / nicosulfuron + rimsulfuron

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
0.66 oz / 0.75 oz 21 Sensitive crops have 10 – 18 month restriction Fall cereal grains, ryegrass Small seeded legumes, mustards, sorghum More persistent in high pH soils (>7)

Active ingredient: pyroxasulfone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
0.133 20 4 mo. for wheat, 11 mo. for other small grains, and 10 mo. for alfalfa Most crops should be fine Food or feed residues rather than crop injury may be a concern Nonfood / feed winter cover crops should be OK after corn harvest

Active ingredient: simazine

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1 – 2 qt 60 Can plant corn, sorghum, and soybean the following year (some products allow others) Sorghum species Cereals, Ryegrass, legumes, and mustards Soil pH > 7

Active ingredient: metolachlor

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1.67 pt 15 – 50 Labeled for use on many crops Almost anything Annual ryegrass or other small seeded grasses Higher rates and later applications more of a potential problem

Active ingredient: tembotrione + thiencarbazone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz 15 Four mo. for wheat, 10 mo. for barley, sorghum, oats and alfalfa Wheat, triticale, rye Small seeded legumes, mustards, sorghum 15 inches of cumulative precipitation required from application to planting rotation crops except wheat

Active ingredient: tembotrione

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz 14 Four mo. for cereal grains, 10 mo. for sorghum, canola, and alfalfa Cereal grains after 4 mo. Unknown – Small seeded legumes, mustards could be a problem Other crops may be seeded after a successful field bioassay.

Active ingredient: topromesone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
0.75 fl. oz 14 Alfalfa, canola, soybean and sunflower have a 9 mo. restriction Wheat, barley, oats, and rye are allowed after 3 mo. Ryegrass should also be OK Although many broadleaves are restricted, Impact does not have much soil activity

Injury Possible

Active ingredient: acetochlor

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
2 pt 10 – 20 Four mo. for wheat and 9 mo. for alfalfa and clovers Most crops should be fine Food or feed residues rather than crop injury may be a concern Nonfood / feed winter cover crops are allowed after corn harvest

Active ingredient: atrazine

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
1 – 2 qt 60 Can plant corn, sorghum, and soybean the following year (some products allow others) Sorghum species Cereals, ryegrass, legumes, and mustards More persistent in high pH soils (>7). Rates <1 lb/acre can allow more flexibility

Active ingredient: dicamba

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
16 to 24 fl. oz 5 – 14 15 days per 8 fl. oz/acre for small grains All crops Only at high rates or less than 120 days after application Anything can be planted after 120 days with 24 fl. oz/acre or less

Active ingredient: dimethenamid

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
16 fl. oz 20 Four mo. for cereal grains and anything the following spring Most crops should be fine Food or feed residues rather than crop injury may be a concern Nonfood / feed winter cover crops should be OK after corn harvest

Active ingredient: metribuzin

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
0.33 lb 14 – 60 Recrop restrictions range from 4 to 12 mo. Cereal grains and ryegrass Slight risk for small seeded legumes and mustards Nonfood / feed winter cover crops allowed

Active ingredient: pendamethalin

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 pt 44 Wheat and barley after 4 mo. Other rotational crops the following year. Cereal grains Small seeded legumes and annual ryegrass Nonfood / feed winter cover crops should be OK

Active ingredient: tembotrione + thiencarbazone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz 15 Four mo. for wheat, 10 mo. for barley, sorghum, oats and alfalfa Wheat, triticale, rye Small seeded legumes, mustards, sorghum 15 inches of cumulative precipitation required from application to planting rotation crops except wheat

Active ingredient: tembotrione

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz 14 Four mo. for cereal grains, 10 mo. for sorghum, canola, and alfalfa Cereal grains after 4 mo. Unknown – Small seeded legumes, mustards could be a problem Other crops may be seeded after a successful field bioassay.

Active ingredient: topromesone

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
0.75 fl. oz 14 Alfalfa, canola, soybean and sunflower have a 9 mo. restriction Wheat, barley, oats, and rye are allowed after 3 mo. Ryegrass should also be OK Although many broadleaves are restricted, Impact does not have much soil activity

Injury Unlikely

Active ingredient: rimsulfuron

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
2 oz 2 – 4 Winter cereals have a 3 mo. restriction and many crops are restricted for 10 mo. Based on the short half-life, most fall cover crops should be OK in PA None More persistent in drought conditions

Active ingredient: saflufenacil

Normal Rate/acre Half life (days) Cash crop restrictions OK (Fall Cover Crops) Concern (Fall Cover Crops) Other
3 fl. oz 7 – 35 Any crop can be planted 4 mo. after application All None This product has been reported more persistent in western Canada

Common soybean herbicides and potential to injure early/interseeded cover crops.

Trade Name Active Ingredient Grasses Legumes Broadelafs
Classic, Canopy, Envive, etc. chlorimuron
Select clethodim
FirstRate cloransulam
Valor flumioxazin
Flexstar, Reflex fomesafen
Raptor imazamox
Pursuit imazethapyr
Assure, Targa quizalofop
Authority sulfentrazone

Information on this page and in the above tables can originally be found at:  Cover Crop Interseeder: Improving the Success in Corn. Retrieved from https://extension.psu.edu/cover-crop-interseeder-improving-the-success-in-corn