Florida Agricultural Experiment Station


usually eat more than half of the potato, hollowing it out on
one side. They seldom eat the main stem of the plant. These
grubs are a fa-
vorite food of
moles which in
tunneling the
ground for the
grubs, do more
damage to the
potato t han do e a b
t e grubs. By FG. 102.-May-beetle or June-bug (Lachnosterna arou-
 grubs. y ata): a, Adult; b, pupa; c, egg; d, young grub; 6,
ridding his fields full-grown grub. Natural size. (From U. S. Bur.
of white grubs
the farmer will greatly lessen the number of moles. Moles do
not, as is commonly supposed, feed on vegetable matter but
break off the roots and subterranean stems of plants in their
search for insects.
 White grubs are slow-growing and very long-lived. All
spend many months in the larval stage, some spending 3 years.
 When full-grown the grubs form pupae (fig. 102, b) in
 earthen cells in the ground. The adults (fig. 102, a) are the
 well-known "June-bugs" or "May-beetles" which are so
 abundant about lights. Like the cutworms, the white grubs
 are active thruout the year in Florida.
 Control.-The only practical control measure is to rid the
ground of the grubs as thoroly as possible before the crop is
planted. This is best done when the ground is plowed. En-
courage chickens and turkeys and such wild birds as crows and
grackles to follow the plow, or turn pigs into the field. It is
particularly important to take these precautions if there has
been much grass on the land. Skunks are persistent enemies
of white grubs as well as other insects and should be protected
by the farmers.
 The large Carrot-beetle (Ligyrus gibbosus) does about the
 same damage as white grubs, has a similar life history and
 calls for identical control measures.

 COLORADO POTATO-BEETLE (Leptinotarsa decemlineata)
 This notorious pest of the Northern potato grower fortun-
 ately has not yet made its appearance in the main potato-grow-
 ing sections of our State. This beetle is present in the northern
 counties of Florida. The infected area is spreading slowly but