20 BULLETIN 902, TJ. S. DEPARTMENT OE AGRICULTURE. 
CLEAN CULTURE. 
The habitual appearance of this species in great abundance on 
young plants is a factor which prohibits the use of anything except 
immediate application of poisonous substances like the arsenicals or 
repellents, but there is little doubt that in the course of time this 
pest will lessen in numbers, provided concerted action is taken to 
control it. Among the best remedies to be employed is the establish- 
ment of clean culture throughout the year from early spring until the 
crop is off and even thereafter. To accomplish this all cruciferous and 
related weeds on which the insects normally feed and breed should 
be kept down. It is desirable, therefore that the grower become 
f amiliar with all of these plants, or else it will be necessary to destroy 
all weeds and keep the fields free from them at all times. This may be 
accomplished by the ordinary process of weeding and by burning 
over after the crop is off and again before the crop is planted. Plow- 
ing over may be sufficient at either time. 
SUMMARY. 
Cabbage, turnips and other cole crops, sugar beets, other vegeta- 
bles, and garden plants, are severely injured in the Western States 
by a minute flea-like beetle known as the western cabbage flea-beetle. 
Injury is chiefly due to the overwintered beetles during June and 
July, but the beetles accomplish more or less injury during the growing 
season. This flea-beetle develops on the roots of wild and cultivated 
cruciferous plants. The beetles frequently appear in great numbers, 
eat minute pitlike holes in the leaves of young plants, and often 
cause considerable injury in seed beds. 
The entire life cycle from egg to adult may be passed in about 30 
days in June and July and there are at least three generations pro- 
duced annually. 
Crops may be protected by means of a spray of arsenate of lead, 
applied at the rate of 2 pounds, powder, to 50 gallons of water, 
or by Bordeaux mixture, 4-4-50 formula, these sprays acting as 
repellents. It can also be controlled by nicotine sulphate, } pint 40 
per cent solution in 50 gallons of water with 2 pounds of soap added, 
and by tobacco dust, which are deterrents. It is not possible, how- 
ever, to control this insect entirely when it occurs in its greatest 
abundance. 
In addition, it is desirable to keep the plants thrifty and well 
watered; mechanical and trap crops can be used with advantage, and 
clean culture is always advisable, especially the destruction of weeds 
in and near cultivated fields. 
