This section is from the book "The Standard Cyclopedia Of Horticulture Vol2", by L. H. Bailey. See also: Western Garden Book: More than 8,000 Plants - The Right Plants for Your Climate - Tips from Western Garden Experts.
Slender, flattened grubs, 3/4inch long when mature, burrowing under the bark and girdling the trees.
-Cut and burn infested trees to prevent spread.
Small, green lice attacking the terminal shoots.
Small, black lice attacking the terminal shoots.
Works in the leaves.
A large, dark brown scale covered with a waxy secretion 1/5inch in length. Surface of scale sculptured like a miniature barnacle.
Resin wash or kerosene emulsion before the waxy covering is secreted.
Small, dull black lice, curling the leaves and killing the new growth.
Contact sprays before the leaves curl.
A black, oval scale 1/4inch in diameter with an "H"-shaped mark on the back of the female. The young are light yellow to brown, unmarked. The scales secrete honey dew in which a fungus grows smutting the fruit.
Fumigation. On citrus, use a half to three-fourths of regular dosage between September and January. On deciduous fruits and olive, water distillate, caustic soda mechanical mixtures or distillate emulsion may be used to kill scales less than one-half grown.
Bright red, minute mite, frequently abundant on fruit and foliage.
Dusting with sulphur or commercial lime-sulfur solution diluted 1-35 or 50 of water.
Slender, minute, orange-yellow insects, less than one-thirtieth inch in length, scarring the fruit and injuring the foliage.
Lime-sulfur solution one part in eighty parts water (likely to cause slight injury to foliage) or "Black Leaf 40" tobacco extract, one part in 1,800 parts water. Make four applications: (1) As the last of petals are falling; (2) ten to fifteen days later; (3) three to four weeks after the second; (4) during the months of August or September (for California). In greenhouses, fumigate with hydrocyanic acid gas.
Red or yellowish scale insects with large, white, fluted, cottony masses which cover the eggs from 1/4 to 1/2inch in length.
Natural enemies, principally by the common Vedalia.
Circular flat, brown scales, 1/16to 1/8 inch in diameter.