Insect Control on Forage Crops

— Written By

R. Brandenburg, D.D. Reisig, and T.L. Billeisen, Entomology and Plant Pathology

Insects pests of pastures and forage crops are often small and difficult to detect unless consistent scouting occurs. This time of year, fall armyworms can be particularly challenging to control. Below are the current recommendations for insect pest control in forages. Be sure to take note of any precautions, remarks and restricted use products.

INSECT

Insecticide and Formulation

Amount of Formulation Per Acre Active Ingredient (lb) per Acre Minimum Interval (Days) Between Application and Harvest Precautions and Remarks (consult all labels for rate and use restrictions) RUP*
ALFALFA WEEVIL
carbaryl (Sevin XLR Plus) 4F 1.5 qt 1.5 7 Larvae only. Maximum of 1.5 quarts and 1 application per cutting.
chlorpyrifos (Lorsban) 4 E 1 to 2 pt 0.5 to 1 7 to 21 Apply as a broadcast foliar spray with 20 gal of water per acre; do not make more than one application per cutting. Phytotoxicity may appear on young plants.
beta-cyfluthrin  (Baythroid XL) 1 EC 1.6 to 2.8 oz 0.0125 to 0.022 7 RUP. Maximum of 0.044 lb. AI per cutting.Not for alfalfa grown for seed. Not for alfalfa-grass mixed stands.
lambda-cyhalothrin (Karate Z, Warrior II) 2.08 CS 1.28 to 1.92 oz 0.02 to 0.03 1 (forage); 7 (hay) RUP. Maximum of 0.03 lb. AI per cutting and 0.12 lb. AI per season.

methomyl (Lannate) 90 LV 

90 SP

3.0 pt

1.0 lb

0.9

0.9

7 (forage); 3 (hay) RUP. Consult label for details and restrictions. REI 48 hr.
phosmet (Imidan) 70 W 1 to 1.33 lb. 0.7 to 0.93 7 Do not apply more than one application per cutting. Do not apply during bloom.
zeta-cypermethrin (Mustang Max) 0.8 EC 2.24 to 4.0 0.014 to 0.025 3 (hay, forage) RUP. Do not apply more than 0.025 per cutting or 0.075 lb. AI per season. 12 hr REI. See label.
ARMYWORM(a) wheat hay
beta-cyfluthrin   (Baythroid XL) 1 EC 1.6 to 2.8 oz. 0.0125 to 0.22 7 RUP. Maximum of 0.044 lb. AI per cutting.
lambda-cyhalothrin (Karate Z, Warrior II) 2.08 CS 1.28 to 1.92 0.02 to 0,03 30 RUP. Maximum of 0.06 lb. AI per season.
methoxyfenozide (Intrepid) 2F 4 to 8 oz 0.06 to 0.12 0 (forage); 7 (hay) Maximum of 0.5 lb. AI per season.
ARMYWORM(b) alfalfa
Bacillus thuringiensis (Agree WG, DiPel DF, Javelin WG, XenTari) 0.5 to 2 lb. product per acre Approximately 15 billion Cabbage Looper Units per lb. 0 Best when larvae are small. Suitable for organic production.
beta-cyfluthrin   (Baythroid XL) 1 EC 1.6 to 2.8 oz. 0.0125 to 0.22 7 RUP. Maximum of 0.044 lb. AI per cutting.
carbaryl (Sevin XLR Plus) 4F 1 to 1.5 qt 1 to 1.5 7 RUP. Do not apply more than 0.06 lb. AI per season.
chlorpyrifos (Lorsban) 75 WG 0.89 to 1.77 lb 0.67 to 1.33 7 to 21 depending on rate Apply as a broadcast spray, but do not apply more than once per cutting. Phytotoxicity may appear on young plants. See label for other restrictions, water volumes, and preplant options.
lambda-cyhalothrin (Karate Z, Warrior II) 2.08 CS 1.28 to 1.92 0.02 to 0.03 1 (forage); 7 (hay)

malathion (Malathion 5) 5 EC

(Malathion 57) 5 EC

1 qt

1 qt

1.25

1.25

0

0

Maximum single application is 1.25 lb. AI. Maximum number of applications is 2 per cutting.

methoxyfenozide (Intrepid) 2F 4 to 8 oz 0.06 to 0.12 0 (forage); 7 (hay) Maximum of one spray per cutting of 0.5 lb. AI.

methomyl (Lannate) 90 LV

90 SP

1.5 to 3.0 pt

0.5 to 1.0 lb

0.45 to 0.9

0.45 to 0.9

7 (forage); 3 (hay) RUP. Consult label for details and restrictions. REI 48 hr.
spinosad (Entrust) 8.8 SC 0.63 to 1.25 oz 0.031 to 0.062 0 (forage); 7 (hay) OMRI listed. Do not apply more than 3.75 oz/season. Rotate with other products.
zeta-cypermethrin (Mustang Max) 0.8 EC 2.24 to 4.0 oz 0.014 to 0.025 3 (hay, forage) RUP.Do not apply more than 0.025 per cutting or 0.075 per season. Three applications per year allowed. 12 hr REI. See label.
ARMYWORM(c) clover
carbaryl (Sevin) 80 WSP XLR 1 to 1.5 qt 1.25 to 1.88 lb
methoxyfenozide (Intrepid 2F) 4 to 8 oz 0.06 to 0.12 0 (forage); 7 (hay

malathion (Malathion 5) 5 EC

(Malathion 57) 5 EC

2 pt

2 pt

1.25

1.25

0

Maximum single application rate is 1.25 lb AI. Maximum of 2 applications per cutting.
ARMYWORM—(d) pasture, grass, grass hay, other forage crops
azadirachtin (Azatin XL Plus, NEemix 4.5) 0.017 EC 0.5 to 1.5 gal  
lambda-cyhalothrin (Karate Z, Warrior II) 2.08 CS 1.28 to 1.92 oz 0.02 to 0.03 1 (forage); 7 (hay) RUP.

malathion (Malathion 5) 5 EC

(Malathion 57) 5 EC

2 pt

2 pt

1.25

1.25

0 Maximum single application rate is 1.25 lb AI. Maximum of 2 applications per cutting.
Bacillus thuringiensis (Agree WG, DiPel DF, Javelin, Xentari) 0.5 to 0.2 lb. product per acre Approximately 15 billion Cabbage Looper Units per lb. 0 Best when larvae are small.
cyfluthrin (Baythroid XL) 1 E 1.6 to 2.8 oz. 0.0125 to 0.22 7 RUP.
methoxyfenozide (Intrepid) 2F 4 to 8 oz 0.06 to 0.12 0 (forage); 7 (hay)
spinosad (Entrust) 8SC 0.63 to 1.25 oz 0.031 to 0.062 3 (harvest) 0 (forage) OMRI listed. For grass crops and pasture.
zeta-cypermethrin (Mustang Max) 0.8 EC 2.8 to 4.0 0.0175 to 0.025 0 (forage); 7 (straw, seed) RUP. See additional restrictions on label.
ARMYWORM(e) pasture
azadirachtin (Azatin XL Plus, Neemix 4.5) 0.017 EC 0.5 to 1.5 gal

malathion (Malathion 5) 5 EC

(Malathion 57) 5 EC

2 pt

2 pt

1.25

1.25

0

Maximum single application rate is 1.25 lb AI. Maximum of 2 applications per cutting.
beta-cyfluthrin (Baythroid XL) 1 E 1.6 to 2.8 oz. 0.0125 to 0.22 7 RUP.
FALL ARMYWORM(a) bermudagrass (also see pasture)
cyfluthrin (Baythroid XL) 1 E 1.6 to 2.8 oz
diflubenzuron (Dimilin) 2L 2 oz 0.03 0 (forage); 1 (hay) Early instars only. Maximum 2 oz. per cutting. Maximum of 6 oz. per year.
methomyl (Lannate) 90 SP 0.25 to 1.0 lb 0.225 to 0.9 7 (forage); 3 (hay) RUP.Consult label for details and restrictions. REI 48 hr.

spinosad (Tracer) 4 SC

Entrust) 8.8 SC

1 to 2 oz

0.63 to 1.25 oz

0.031 to 0.062

0.031 to 0.062

14

Do not allow cattle to graze until spray has dried. Entrust is OMRI listed.
zeta-permethrin (Mustang Max) 0.8 EC 2.8 to 4 0.0175 to 0.025 0 (forage, hay); 7 (straw, seed) RUP.See label for additional restrictions.
FALL ARMYWORM(b) rye and pasture
carbaryl (Sevin) 80 WSP XLR Plus 4F 1 to 1.5 qt 1.25 to 1.88 lb  
beta-cyfluthrin (Baythroid XL) 1 E 1.6 to 2.8 oz. 0.0125 to 0.022 7 RUP.
diflubenzuron (Dimilin 2L) 2 oz 0.03 0 (forage); 1 (hay) Early instars only. Maximum 2 oz. per cutting. Maximum of 6 oz. per year.

spinosad (Tracer) 4 SC

(Entrust)8.8 SC

1.5 to 3 oz

0.63 to 1.25 oz

0.047 to 0.093

0.031 to 0.062

3

14

Entrust is OMRI listed. For grass and pasture.

FALL ARMYWORM(c) alfalfa and clover
carbaryl (Sevin) 80 WSP XLR or SL 1 to 1.5 qt 1.25 to 1.5 lb
beta-cyfluthrin (Baythroid XL) 1 E 1.6 to 2.8 oz. 0.0125 to 0.22 7
lambda-cyhalothrin (Karate Z, Warrior II) 2.08 CS _ __ 30 (harvest) RUP. Consult label for directions.Alfalfa only. Not for clover.
methomyl (Lannate) 90 SP 0.5 to 1.0 lb 0.45 to 0.9 7 RUP.
zeta-cypermethrin (Mustang Max) 0.8 EC 2.8 to 4.0 oz 0.0175 to 0.025 0 (forage); 7 (straw, seed) RUP. See additional restrictions on label.
(d) wheat hay
lambda-cyhalothrin (Karate Z, Warrior II) 2.08 CS 1.28 to 1.92 oz 0.02 to 0.03 30 (harvest) RUP. Consult label for details. Wheat hay only.
spinosad (Entrust) 0.63 to 1.25 oz 0.031 to 0.062 3 (harvest); 0 (forage) OMRI listed. For grass and pasture.
zeta-cypermethrin (Mustang Max) 0.8 EC 2.8 to 4.0 0.0175 to 0.025 7 (up to 3 days after cutting) RUP.Do not make applications less that 7 days apart. Maximum of 0.025 lb. AI per application and 0.075 lb. per season.
FIRE ANTS(pasture)
Fenoxycarb (Award) 1% bait 1 to 1.5 lb
hydramethylnon (Amdro Pro or Siege Pro)0.73% bait 1 to 2 lb 0.0073 to 0.011 7 (cut or bale) For mound or broadcast. Can be applied to grass forage in North Carolina but not labeled for some states. Consult label for any additional restrictions and directions in using this bait in pasture. 
Hydramethylnon (Amdro) 1 to 1.5 lb May be used in corrals and other animal holding areas but not for use in hay pastures or where livestock are used for food or feed production.
methoprene (Extinguish) 0.5% bait 1 to 1.5 lb 0.005 to 0.0075 7 (cut or bale) For mound or broadcast. Distribute uniformly 5 to 7 level tablespoons of bait 3 to 4 feet around base of mound for individual mound treatment. 
methoprene + hydramethylnon (Extinguish Plus)0.25% and 0.365% bait 1.5 lb. 0.0092 7 (cut or bale) For mound or broadcast. Can be applied to grass forage in North Carolina but not labeled for some states. Do not bale and cut treated pastures and rangelands for 7 days post-application unless used to support companion animals (horses, llamas etc.).
pyriproxyfen (Esteem Ant Bait) 0.5% bait 1to 2 lb 0.0075 to 0.01 For pasture grass and rangeland, the pre-harvest interval is 0 days. Do not plant any crop other than those with registered pyriproxyfen uses in treated areas sooner than 30 days post-application.
carbaryl (Sevin) 4F 1.5 oz per gallon of finished product _ _ For pasture fire ant mound drench.
GRASSHOPPER, CRICKET
carbaryl (Sevin) 80 WSP 1.25 lb
chlorpyrifos (Lorsban) 75 WG 0.44 to 0.9 lb 0.33 to 0.67 14 Apply no more than one application per cutting.Alfalfa only.
cyfluthrin (Renounce) 25 WP 3.2 to 3.5 oz 0.04 to 0.044 7 RUP.Maximum 5-day treatment interval; maximum 14.1 oz per year. See label – many restrictions.
diflubenzuron (Dimilin) 2 L 1 to 2 oz 0.016 to 0.03 1 day Limit of 2 oz per spray and 6 oz per season. Grassland pasture. Restricted use pesticide.
malathion (Malathion 57) 5 EC 1.5to 2 pt 0.94 to 1.25 lb 0 Limit of 1.25 lb. AI per acre spray and 2 applications per cutting.
GRUB, GREEN JUNE BEETLE
carbaryl (Sevin) 80 WSP XLR Plus 4F 1 to 1.5 qt 1.25 to 1.88 lb
LEAFHOPPER (see also Potato Leafhopper)
carbaryl (Sevin) 80 WSP XLR Plus 4F 1 to 1.5 qt 1.25 to 1.88 lb
chlorpyrifos (Lorsban) 4 EC 0.5 to 1 pt 0.25 to 0.5 14 Apply no more than one application per cutting.
dimethoate (Dimethoate 400) 4E 0.5 to 1 pt 0.25 to 0.5 10 Do not apply more than one application per cutting. Maximum application rate is 0.5 lb AI per acre. Do not apply during bloom.
PEA APHID, SPOTTED ALFALFA APHID
beta-cyfluthrin   (Baythroid XL) 1 E

2.8 oz

0.022

7

RUP. Maximum of 0.025 lb AI per cutting; 0.1 lb AI per year.
dimethoate (Dimethoate) 4 EC 0.5 to 1 pt 0.25 to 0.5 10 RUP. One application per cutting.
malathion (Malathion 57) 5 EC 1.5 to 2 pt 1 to 1.25 0 Cutting hay as soon as practical minimizes damage by aphids.
lambda-cyhalothrin (Karate Z, Warrior II) 2.08 CS 1.28 to 1.92 oz 0.02 to 0.03 1 (forage); 7 (hay) RUP. Maximum of 0.03 lb. AI per cutting and 0.12 lb. AI per season.

methomyl (Lannate) 90 LV

90 SP

1.5 to 3.0 pt

0.5 to 1.0 lb

0.45 to 0.9

0.45 to 0.9

7 (forage); 3 (hay) RUP. Consult label for details and restrictions. REI 48 hr.
zeta-cypermethrin (Mustang Max) 0.8 EC 2.24 to 4 oz 0.014 to 0.025 3 (cutting or forage) RUP. Maximum of 0.025 lb. AI per cutting; 0.075 lb. AI per year.
POTATO LEAFHOPPER Usually potato leafhoppers occur in July and August but also can migrate from the Gulf region and sometimes appear in high numbers in June.
beta-cyfluthrin   (Baythroid XL) 1 E

1 to 2 oz

0.008 to 0.0155

7

 

RUP. Maximum of 0.025 lb AI per cutting; 0.1 lb AI per year. Refer to label for higher rates needed for threecornered alfalfa hopper.
carbaryl (Sevin) XLR Plus 1 to 1.5 qt 1 to 1.5 14
chlorpyrifos (Lorsban) 4E 0.5 to 1 pt 0.25 to 0.5 7 (0.5 pt); 14 (1 pt) RUP. One application per cutting and limited to four applications a year. Phytotoxicity may appear on young plants.
dimethoate (Dimethoate) 4 EC 0.5 to 1 pt 0.25 to 0.5 10 RUP. One application per cutting.

lambda-cyhalothrin (Karate Z, Warrior II) 2.08 CS

alfalfa

other pasture

asdasdasdasd

asdasd

0.96 to 1.6

1.28 to 1.92

asdasdasdasd

asdasd

0.015 to 0.025

0.02 to 0.03

1 (forage); 7 hay for both crops

RUP. Maximum of 0.03 lb. AI per cutting and 0.12 lb. AI per year for both crops.
zeta-cypermethrin (Mustang Max) 0.8 EC 2.24 to 4 oz 0.014 to 0.025 3 (cutting or forage) RUP. Maximum of 0.025 lb AI per cutting; 0.075 lb. AI per year.
SPITTLEBUG
chlorpyrifos (Lorsban) 4 EC 1 pt  
zeta-cypermethrin (Mustang Max) 0.8 EC 2.24 to 4 oz 0.014 to 0.025 3 (cutting or forage) RUP. Maximum of 0.025 lb AI per cutting; 0.075 per year.

BERMUDAGRASS STEM MAGGOT

 

May require 2 applications starting within 7 to 10 days after harvest
Besiege (chlorotranilprole + lambda-cyhalothirn) 6-10 oz 0 day harvest or grazing restriction restriction
Baythroid XL1 (beta-cyfluthrin) 1.6-1.9 oz Do not harvest hay within 7 days, 0 day grazing restriction
Karate2.08, Warrior II (Lambda-cyhalothrin) 1.3-1.9 oz Do not harvest hay within 7 days, o day grazing restriction
Mustang Max 0.8 (Zeta-cypermethrin) 2.8-4.0 oz 0 day harvest or grazing restrictionrestriction