8 Farmers’ Bulletin 1193. 
feeding for from three to four weeks before entering the ground to 
pupate. The pupa stage lasts 8 or 9 days. During September the 
beetles leave their food plants and go into winter quarters. 
NATURAL ENEMIES. 
Ladybird beetles of three species devour the eggs of this insect. 
A bug’ feeds on the larve and beetles. Mites and spiders also 
attack it, as does a fungous disease.* Wild birds of several species 
prey upon it and chickens feed readily on the beetles and have been 
utilized to advantage in de- 
stroying this leaf-beetle. 
CONTROL MEASURES. 
Taking advantage of the 
fact that the beetles pass 
the winter in alkali areas 
under tufts of grass, espe- 
cially “tickle grass,” dead 
weeds, and other rubbish, it 
is possible, by thoroughly 
burning these during the winter, to destroy the beetles in great num- 
bers, as has been practically demonstrated. They may be trapped by 
placing heaps of weeds or bunches of straw or hay in these alkali areas 
which they frequent, and after they have gone into hibernation, the 
traps with the beetles are destroyed by burning. If this is done thor- 
oughly, immense numbers may be destroyed, but careless, slipshod 
work will invariably fail to produce the desired result. The best 
time for this work is between the middle of November and the first 
week of March, when the dead grass and weeds may be easily burned. 
Thorough tests with arsenicals and other insecticides have been 
made but without perfectly satisfactory results, neither dusting nor 
spraying being entirely effective. 
lia, 8.—The convergent ladybird, an enemy of the 
beet leaf-beetle. Enlarged. 
®°The most useful are Hippodamia convergens Guer. (fig. 8), H. sinuata Muls., and H. 
glacialis Fab. 
7 Perillus bioculatus Fab., var. clawdus Say. 
8 Botrytis bassiana, 
WASHINGTON : GOVERNMENT PRINTING OFPICH : 1921 
