Potato leafhoppers continue to migrate into the state from the south, laying eggs 

 in alfalfa. These small, green, wedge-shaped insects that skid sideways when dis- 

 turbed cause yellowing of second and third cuttings. They not only reduce yields, 

 but also lower the vitamin A and protein content of the hay. Populations appear 

 to be heavier than normal; damage could be more pronounced this year. 



Leafhopper abundance can be detected by shaking the plants over a piece of paper. 

 If swarms of these insects are observed at cutting time, treatment of the new 

 growth is indicated. Spray when the new growth is 2 to 6 inches tall with either 

 1 pound per acre of actual carbaryl (Sevin) or methoxychlor . Allow 7 days to 

 elapse between treatment and harvest when using methoxychlor. There is no waiting 

 period for carbaryl. 



Small-Grain Insects 



The number of true armyworms remained low in the fields observed this week, and 

 it appears that this may be a light year for them. The worms found in the central 

 and south-central sections were about 1/2 to 1 inch in size, with the highest 

 counts in thick, rank, lodged spots averaging about 1 per foot of row. No reports 

 of control applications have been received at this time. 



English grain aphid populations have increased in wheat, particularly in the west- 

 southwest and southwest sections. Counts range as high as 20 aphids per head. 

 It takes an average of 30 to 50 aphids per head to cause measurable damage. Make 

 a careful count, taking head samples in several areas of the field to obtain an 

 average figure. If control is indicated, have a commercial applicator apply methyl 

 parathion at 1/4 pound of actual chemical per acre. There is a 15-day waiting pe- 

 riod between treatment and harvest for methyl parathion. 



Homeowner Insect Problems 



Bagworm hatch is now complete in southern sections, and sprays should be applied 

 immediately. The target date for spraying in the central sections is after 

 June 15; in northern sections, after June 30. 



Make plans to apply treatments early this year, while the worms are still small 

 and easy to kill and before damage is evident. Carbaryl (Sevin), diazinon, or 

 malathion are all effective. Malathion will also provide fair control of mites 

 that might be present. Follow label directions and check the plants that may be 

 injured if sprayed with the insecticide you are using. 



Oystershell scale hatch is about complete in the central and southern sections ; 

 sprays will control them if applied during the next few weeks. In northern sec- 

 tions, sprays should not be applied until after June 15, when hatch is complete. 

 Careful and thorough spraying with malathion (2 teaspoons of 50- to 57 -percent 

 liquid concentrate per gallon of water) will effectively control oystershell scale. 

 An additional treatment will likely be needed in early to mid-August for second 

 generation crawlers. Even though scales are killed by spraying, the scale cover- 

 ing will persist for several months. 



Chiggers will be a problem soon. They annoy campers, hikers, picnickers, fisher- 

 men, and berry pickers--even homeowners in their own yard on occasion. When enter- 

 ing possible chigger- infested areas, use a repellent such as DEET (diethyl toluarnide) 





