-2- 



The following insecticides are suggested for alfalfa iveevil control: 



1- Methoxychlor, 1 pound; plus diazinon, 1/2 pound (Alfatox) per acre . It is ef- 

 fective for approximately 10 to 14 days. Do not harvest for 7 days after treat- 

 ment. 



2. Malathion,! pound per acre . It is effective for approximately 5 to 7 days. 

 Do not apply if air temperatures are below 60° F. , since failure may result. 

 There is no waiting period between treatment and harvest. 



3. Methoxychlor, 1 pound per acre . It is effective for approximately 5 to 8 days. 

 Do not harvest for 7 days after treatment. 



4. Methyl parathion, 1/2 pound per acre . FOR USE ONLY BY EXPERIENCED APPLICATORS. 

 It is effective for approximately 8 to 12 days. Do not harvest for 15 days 

 after treatment. 



5. Azinphosmethyl (Guthion) , 1/2 pound per acre . FOR USE ONLY BY EXPERIENCED 

 APPLICATORS. It is effective for approximately 10 to 14 days . Do not apply 

 more than once per cutting. Allow 16 days between treatment and harvest. 

 Water temperature for the spray mix should be above 55° F. 



The critical period for clover leaf weevil is over in the southern half of the 

 state. Most of the larvae have pupated or died from a fungus disease. Only oc- 

 casional larvae can be found and clover and alfalfa stands should be able to out- 

 grow any further feeding. In the northern half of the state, observe clover and 

 alfalfa fields (particularly new seedings with heavy trash covers) closely for the 

 next week or two. If weevil feeding begins to get ahead of plant growth, a spray 

 of 1 pound per acre of malathion is effective. Pea aphids are also controlled by 

 malathion. 



Pea aphids are still heavy in some alfalfa and clover fields but, in general, lit- 

 tle injury is evident. Parasites and predators of aphids are helping to reduce 

 numbers. Cool weather favors aphid development, while warm weather is detrimental 

 to aphids, since natural enemies are more active. There may be an occasional field 

 needing treatment. If plants show wilting and aphids are heavy, spray with 1 pound 

 of actual malathion per acre. 



English grain aphid populations continue high in some wheat fields. There are many 

 aphid predators present (syrphid fly maggots, lady beetles, aphis lions), which are al- 

 ready reducing aphid numbers. We have observed many fields of wheat in poor condi- 

 tions, but diseases (not aphids) were the cause. No control need be applied for 

 aphids unless the plants show wilting. There will be reason for concern if aphid 

 numbers remain high until wheat begins to head out. After wheat heads appear, it 

 takes an average of 50 to 50 aphids per head to cause measurable damage. Ordinar- 

 ily, the aphids . ill leave the wheat head as it enters the dough stage. If con- 

 trol of grain aphids becomes necessary, apply 1 pound of malathion per acre. Al- 

 though you can apply malathion to within one week of harvest, that would be far 

 too late for profitable control of grain aphids. Experienced applicators can apply 

 1/4 pound of parathion or demeton (Systox) per acre. Allow 15 days between treat- 

 ment and harvest for parathion and 45 days for demeton. 



Armyworm moths arc moving northward from states to the south of us. These first 

 moths will lay eggs in grass in fence rows, ditch banks, roadsides, and pastures 



