Types of Garden Enemies
Fig. 61
The caterpillars are very hairy, about an inch long, pale yellow with black spots, and they fill the webs with black pellets of excrement. They winter in cocoons under trash on the ground or under tree bark, and the moths lay eggs on leaves in spring. The first generation webs and feeds for about a month, in June, and the second generation works in late summer, its webs being more numerous and spectacular than those of the first brood.

Control. For small ornamental trees it is quite feasible to cut off the webbed branches and burn the nest. The spray schedule for codling moth controls web worms on apples; on shade trees either DDT or lead arsenate is effective if applied when the caterpillars are only half grown.

JUNIPER WEBWORM (Dichomeris marginella).
Needles of some juniper varieties are webbed together with silk enclosing reddish-brown caterpillars and a large amount of frass. Sometimes the whole top of a small juniper is webbed together with branches turning brown, sometimes dying. Moths lay eggs in June in new terminal growth, and half- grown larvae winter in silken cases in webbed foliage.

Control. Cut out webbed masses where possible. Spray in summer when larvae are young with DDT (adding a miticide to prevent build-up of spruce mite) or with lead arsenate. In spring try pyrethrum or nicotine sprays applied with force enough to break webs.

PINE WEBWORM (Tetralopha robustelld).
Needles near the end of terminal twigs are webbed together with silk containing conspicuous masses of brown frass. If you pull these webs apart in early June, you can usually find hiding rather fat, inch-long caterpillars, olive green with a brown stripe along the body. I have seen young pines severely injured; larger trees are somewhat disfigured but not really harmed. A DDT spray applied in May should help; by the time people notice the webbing and frass, the insect is signing off for the season anyway.

SOD WEBWORMS (Crambus spp.).
These are the lawn moths that fly up in a zigzag motion when you walk across the grass at dusk. They have a pronounced projection from the head, are golden to pale brown, and when at rest their wings are folded so close to the body they look like little cylinders. The fat larvae, much like cutworms, live in silk-lined tunnels or tubes in the soil. The young caterpillars skeletonize grass blades, and older larvae cut them off.

Control. Apply 5% chlordane dust, or water the soil with lead arsenate, using 1 pound to 200 square feet. Pyrethrum or dichlorethyl ether sprays can be used for temporary control.




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