542 ANNUAL REPORT OF THE Off. Doc. 



such insects as these on any kind of plants, but those insects, like 

 plant lice, that do not jump readily must be brushed against it. This 

 is such a cheap and eft'ective device that it should come into general 

 use. 



4. Board Traps. (Fig. 44.) 



Simply flat boards are placed on the ground around plants, and 

 as it is warmer under them at night than in the air above them, in- 

 sects of certain species congregate there and in the morning may be 

 brushed off into a can or tray of kerosene and water and thus killed 

 at once. 



This is especially recommended for squash bugs, cut worms, false 

 army worms, crickets, slugs, etc. 



II. FARM PRACTICE. 



1. Clearing up all Rubbish. 



It is particularly important that this be done late in the fall and 

 in the winter. If debris of all kinds available then be raked together 

 and burned many hibernating insects will thus be killed. However, 

 it is advisable that a watch be kept for toads which hibernate under 

 leaves, etc. These animals are of great value as destroyers of in- 

 sects and slugs and they should be preserved with care. They are 

 too fretjueutly burned with leaves and rubbish in the winter time. 



Eail fences are favorite places for insects like the squash bug to 

 pass the winter in hibernation, as well as favorable to the growth of 

 weeds. TN'ire and board fences can be kept cleaner and consequently 

 will contribute toward keeping down insect pests. 



2. Clearing Away Unused Portions of Crops. 



Just as soon as the desired portion of a crop is gathered the remain- 

 ing parts of the plants, green fruits, stems, leaves, roots and all, 

 should be burned, buried or thrown in a heap to decay. The late 

 fall brood of nearly all species of insects mentioned in this Bulletin 

 would be reduced if this practice were general. This means that but 

 few individuals would be able to live through winter and infest the 

 crops for a new brood in spring. 



If at any time plants or parts of plants are killed by insects they 

 should be burned at once. This is a general principle of great im- 

 portance and applies to all crops. 



3. Killing all Weeds. 



Since some of the insects (particularly the plant lice and flea- 

 beetles) mentioned above feed on several kinds of weeds it is very 

 important that the premises be kept free from weeds, because other- 

 wise the pests are able to multiply on the uncultivated plants and 

 from them, constantly come to infest the cultivated crops. 



