BEETLES
Beetles comprise nearly a third of all the named insects. They have
chewing mouthparts and are injurious in both larval and adult stages.
Their front wings (elytra) are hardened and thickened to serve as a
convex shield for the membranous hind wings used in flight. Most
beetles are rather oval in shape, their wing covers meeting in a straight
line down the back. Beetles with the head prolonged into a long curved
snout are known as curculios, those with a short snout are often called
weevils. A beetle with short, chunky mouthparts usually feeds on plants
and so is a garden enemy, but those with long, curved mandibles prey
on other insects and so become our friends.
Beetles have complete metamorphosis; the adult is completely unlike the
larva, called a grub, the transformation being made in a pupa. Some
beetle grubs remain in the soil, feeding on roots, some are borers in
woody stems, and some are leaf feeders, skeletonizing foliage.
ASIATIC GARDEN BEETLE (Autoserica castanea)
, a pest in the suburban
New York area and found in scattered locations along the Atlantic
seaboard from Massachusetts to South Carolina. The adult, a rich chestnut brown, 3/8 inch long, hides in the soil during the day, coming out
at night to feast on asters, chrysanthemums, dahlias, zinnias, and other
ornamentals, sometimes beet, carrot, corn, eggplant, or pepper. In its
nocturnal wanderings it bangs against screens and flies into automobiles.
It should not be confused with May or June beetles which do the same
thing and are sometimes nearly the same color but much larger and
found in many more states.
The period of activity, late June to early September, coincides with
that of Japanese beetles, the grubs feed on grass roots in the same way
spring and fall, and in general the same control measures apply. Treat
turf with chlordane or DDT; spray or dust ornamentals with DDT,
methoxychlor, or lead arsenate; dust vegetables with rotenone.
ASPARAGUS BEETLE (Crioceris asparagi),
a pest wherever asparagus is
grown except in California. The beetles are slender, % inch long,
metallic blue to black with orange or yellow markings. They winter in
protected places in the garden; in spring they gnaw tender shoots and
blacken them with rows of dark eggs standing on end. The larvae, olive
gray, humped, rather sluglike, also devour shoots and the feathery summer foliage. There may be 2 to 5 generations a season.
The SPOTTED ASPARAGUS BEETLE {Crioceris duodecimpunctatd) is present East of the Mississippi. The adults, reddish orange with 12 black
spots, feed on shoots and foliage, laying green eggs on the leaves just
before berries form. The orange larvae feed only on the berries.
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Types of Garden Enemies
