FALL ARMYWORM {Laphygma frugiperda).
This is a year-round pest in
the Gulf States, but it migrates North. The caterpillars are tan
or green or nearly black with yellowish lines and a conspicuous white
V on the head. They prefer grass, go to corn as a second choice, and then
many vegetable crops. When all the food in one garden has been eaten,
the army marches on to the next.
BAGWORMS
BAGWORMS (Thyridopteryx ephemerae for mis and related species)
are caterpillars that carry their houses around with them in the form of
spindle-shaped bags, 1 to 11/2 inches long, covered with bits of leaves and
twigs of the tree being fed upon, bags hanging on junipers differing from
those on pines or deciduous trees. Bagworms are fairly general feeders
on trees and shrubs, but they are special pests of arborvitae, juniper, and
larch and often injurious to spruce, pine, and hemlock. They are common
in the North but somewhat more injurious in the South. I have seen arborvitae killed in Texas and miles of red-cedars dying in Virginia. Larch is
sometimes entirely defoliated.
Eggs winter inside the bag, and the larvae hatch in very late spring,
June in some states. Each young black and white worm crawls out,
starts to feed, and immediately starts to spin its own bag, keeping its
body inside this as it moves about. In late summer the female changes
inside the bag to a wingless moth, is visited by the furry, black, winged
male, lays her eggs, and dies.
Control. If there are only a few bags and you can reach them, by all
means cut them off for burning during the winter or early spring. DDT
does not control bagworms. Spray as larvae hatch (May in the South,
early June in New York) with lead arsenate, using 3 level tablespoons
per gallon of water. Parathion and other phosphates will kill older caterpillars, but nurserymen can use these more safely than home gardeners.
Toxaphene is reported effective.
BEES
Bees are so tremendously important in pollinating plants we should
not mind a few harmful effects. Small carpenter bees nest in tunnels in
pithy plants and leafcutting bees disfigure some foliage.
LEAFCUTTER BEES (Megachile spp.).
These are solitary bees, medium-sized,
hairy, with long legs, nesting in burrows in old wood or hollow
stems of plants. They cut perfect ovals and circles from the margins of
leaves, preferably rose leaves, using the ovals to line the sides of their
nests, and the round portions as partitions between the 10 or 12 cells,
each containing pollen, nectar, and an egg, in their burrows. Because the
bees do not eat the leaf tissue, they are not readily poisoned. Besides, it
would be a shame to kill these intriguing insects which work with such
mathematical exactness and are important pollinators.
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Types of Garden Enemies
