Types of Garden Enemies
But as adults they can be quite injurious, ravaging flowers and foliage of Japanese anemones, asters, etc., in late summer in the North and attacking a great many vegetables and ornamentals through the season in the South.

Control. Dust ornamentals with DDT, vegetables with cryolite or a pyrethrum-rotenone combination. Wear gloves if you pick these beetles off by hand. They contain cantharidin, a chemical that can blister the skin.

COLORADO POTATO BEETLE (Leptinotarsa decemlineata).
A native insect, primarily a potato pest but occasionally feeding on petunia, nicotiana, pepper, tomato, eggplant, and related plants. The adult, 3/8 inch long, with black and yellow stripes lengthwise of its very convex wing covers, winters in the soil, laying egg clusters in spring on underside of leaves. The humpbacked larvae are reddish with black spots, just over 1/2inch long. They pupate in the soil, and there are usually 2 generations.

Control is easy now with DDT, a 3 or 5% dust, or a spray using 2 tablespoons 50% wettable powder to a gallon of water. Some of our grandfathers had to spend their summers picking off potato "bugs."

ELM LEAF BEETLE (Galerucella xanthomelaena).
As you drive through the country in summer you feel sick at the sight of all the elms along the highways with their leaves brown and full of holes, half of them already on the ground. Trees so weakened are easy prey to bark beetle vectors of Dutch elm disease. Many of the beetles winter in houses, crawling in around the screens in late summer to hide until spring when they fly back to the elms. They lay yellow, lemon-shaped eggs in short double rows on young foliage, and the sluglike black and yellow larvae skeletonize the leaves, eating out everything but epidermis and veins. After feeding about 3 weeks they crawl down the trunk to pupate. The beetles are 1/4 inch long, yellowish or olive green with a dark stripe near the outer edge of each wing cover; they chew irregular holes clear through the leaf tissue. There are 2 or 3 generations, the overwintering beetles being rather dull in color.

Control. Have trees sprayed thoroughly with lead arsenate, 6 pounds per 100 gallons, or with DDT, 2 pounds 50% wettable to a 100, when they come into full foliage; repeat in July if necessary.

CUCUMBER BEETLES.
The Striped Cucumber Beetle (Acalymtna vittata) is the most serious pest of cucurbits, cucumbers, melons, squash, pumpkin, gourds, east of the Rocky Mountains and the Western Striped Cucumber Beetle (A. trivittatd) takes over for the Pacific Coast. The larvae are slender rootworms, 1/3 inch long, white with brown ends, tunneling in roots and underground parts of stems.




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