INSECTS AND OTHER ANIMAL Pests InJuRIoUS TO FreLp BEANS 1005 
than one-fourth as many flea beetles were present as there had been the 
year before. The food supply of the young larvae was removed at a 
critical time, apparently causing many to die of starvation. 
The parent beetles are often numerous on ragweed and lamb’s-quarters 
growing among wheat and oat stubble in the fall; and it has been noticed 
that when beans were planted in these fields the following year, the beetles 
were often abundant. Beans grown on land that had previously been 
in clover in which some ragweed 
had also sprung up, often show 
as heavy an infestation of S. 
taenvata. If sod land or stubble 
land of this type is plowed deep 
in September, when the larvae 
are small, so as to destroy the 
larval food supply, it is probable 
that the infestation of the follow- 
ing spring will be much reduced. 
Artificial control measures 
tested against S. taenzata and the 
red-headed flea beetle, S. fron- 
talis, are discussed on page 1009. 
THE RED-HEADED FLEA BEETLE 
(Systena frontalis Fab.) 
A rather large, black flea 
beetle, with a red head, Systena 
frontalis (of the family Chryso- 
melidae), may be found more or 
less abundant in bean fields in 
New York every year. In dry 
seasons it is often numerous 
enough to cause considerable Fic. 93. BEAN PLANTS DAMAGED BY THE RED- 
damage to the foliage (figs. 93 HEADED FLEA BEETLE 
and g4). This insect has been A few beetles may be seen on the plants 
found at Perry, New York, each 
year since 1917, and in 1918, when there was little rain, many beans turned 
yellow as a result of the feeding of this species and the closely related 
form, S. taeniata. Thirty beetles have been counted feeding on the upper 
surface of the leaves of a single plant. They often congregate on a few 
plants, seriously damaging them, while other plants are almost free from 
the pests. 
S. frontalis is a common insect in the United States east of the Rocky 
Mountains, and in parts of Canada. It has been reported as injurious 
to grapes, cabbage, beets, potatoes, corn, beans, clover, cranberries, goose- 
berries, mangle-wurzels, and pear leaves. It is known to occur also on 
