34 MISC. PUBLICATION 657,.U. S. DEPT. OF AGRICULTURE 
As the mash dries, it becomes less attractive, so it 1s necessary to 
apply it when the grasshoppers are beginning their first feeding of 
the day, usually early i in the morning. Duri ing “migrations the hoppers 
may feed at almost any time where food is found. In such case the 
bait should be spread on a clear day, when the temperature is between 
70° and 85° F. An easy way to determine whether conditions are 
right for bait spreading is to scatter a few handfuls where the grass- 
hoppers are thick. If feeding begins at once, spreading should be 
continued. 
Most sawdusts if fairly fine and a year or more old are suitable, 
although fresher sawdust from cottonwood can be used; fresh pine 
sawdust is not suitable. A bulletin by Parker (329) gives detailed 
discussions of control inethods. 
According to Snyder (392), the lesser cornstalk borer (2lasmo- 
palpus lignosellus (Zell.)) can be controlled with the bran mash 
recommended for grasshoppers. 
LEAF-CHEWING INSECTS 
A great many species of insects feed on the foliage of nursery plants, 
but these can ‘be discussed in a few broad groups, as the control 
measures for the species within a given group are very similar. The 
common method of control is to spray a poison, or contact spray on 
the infested foliage, so that the poison will be eaten with the food 
of the insect. 
Caterpillars and Slugs 
Caterpillars and slugs can be readily controlled by applying con- 
tact sprays as described on pages 52-53. 
Tip Moths 
Tip moths boring in the ends of branches are not so destructive in 
the nursery, but the danger lies in carrying the infestations to planta- 
tions with infested nursery stock. Infested stock should be dipped 
in a miscible-oil insecticide. See page 54, formula 10. 
For more information on the tip moths the reader is referred to 
Graham and Baumhofer (295, 796), and Friend and West (177). 
Blister Beetles 
Spraying the foliage with 114 pounds of lead arsenate to 50 gallons 
of water will usually protect the seedlings, largely by repelling the 
beetles, although some of the beetles will be ‘poisoned. Bordeaux 
mixture, a common fungicide, is also repellent to these beetles. Com- 
bining the lead arsenate with bordeaux mixture should give better pro- 
tection than the arsenical alone where the beetles are numerous. As 
the new growth comes out, beetles will return to feed on this unpro- 
tected foliage, and it will be necessary to spray several times to give 
good protection. The use of a sticker in the spray is not advisable 
where these repeated appl cations are made. 
Bordeaux mixture may cause gastric disturbances if taken in- 
ternally. It is also somewhat irritating to the eyes and skin. 
