112 MANUAL OF VEGETABLE-GARDEN INSECTS 



young ]:>lants by covering them with some kind of screen. 

 Cheesecloth, mos(iuito-nettiiig and wire screen are often used 

 for this purpose, ^'arious methods are followed to hold the 

 covering in place over the plants ; sometimes a shallow wooden 

 box is used, open at top and bottom and the screen is tacked 

 over the top ; sometimes a barrel hoop is cut into halves, the 

 two parts crossed at right angles and the ends stuck in the 

 ground ; the screen is placed over the hoops and earth thrown 

 on the edges to hold it down ; sometimes the cover is made 

 entirely of wire screen in the form of a cone and one grower 

 successfully used wire pie-covers. The difficulty in using covers 

 is that they have to be removed before the plants become very 

 large and if the beetles are very abundant injury may follow. 



INIuch may be accomplished to prevent injury by keeping 

 the plants thoroughly covered with bordeaux mixture or arse- 

 nate of lead (paste), 3 pounds in 50 gallons of water. This 

 renders the plants distasteful to the beetles and is especially 

 valuable on cucumbers if used in connection with trap crops. 

 Squashes are often more attractive to the beetles than cucum- 

 bers and have been used successfully for trap crops. When it 

 is desired to protect a field of cucumbers, a few rows of squashes 

 should be placed around the field about a week before planting 

 the cucumbers ; another planting of squashes should be made 

 at the time the main field is set and if the beetles are abundant, 

 more squashes should be planted about a week later. The 

 beetles will collect on the squash plants, where it is sometimes 

 possible to poison some when they first arrive and before they 

 have had a chance to feed on unpoisoned foliage. Only a part 

 of the trap crop should be sprayed or dusted with the poison 

 for fear of driving the beetles to the cucumbers. Whenever a 

 trap crop is used, it is important to keep the main crop well 

 sprayed with bordeaux mixture or arsenate of lead. Experi- 

 ments in New Hampshire have shown that arsenate of lead is 

 just as effective as a deterrent for the beetles as bordeaux 



