26 MASS. EXPERIMENT STATION BULLETIN 353 



which are usually spun in folded leaves but sometimes in crevices of the bark, on 

 buildings, on fences, in rubbish, and in other places near their host plants. About 

 10 days later the white, sating' moths begin emerging. In late June and during 

 July the moths are on the wing. They soon mate and the females lay their eggs 

 in small masses on the bark, leaves, or adjacent fences or buildings. The eggs 

 hatch in about 2 weeks. The tiny caterpillars of the first two stages feed on 

 either surface of the leaves, usually the lower, skeletonizing them. After feed- 

 ing for several daj's the first stage caterpillars spin a thin, small web in a bark 

 crevice or on the back of a leaf and change to the second stage. They feed for 

 about the same length of time and then spin a small, firm web or winter case in 

 which they change to the third stage, in which they hibernate. Usually there is 

 only one caterpillar to a web but in severe infestations two or more may occur. 

 There is one generation a year. 



Control. The best control is obtained by spraying the foliage with lead arsenate 

 in the spring to kill the caterpillars when they begin to feed. To 5 pounds of lead 

 arsenate and 100 gallons of water add \H pints of light pressed menhaden fish 

 oil or raw linseed oil to make the spray adhere to the waxy foliage of the host 

 plants. The lead arsenate should be mixed with a small amount of water and 

 stirred to form a thin paste. The oil should then be added, stirred until evenly 

 distributed, and then poured into the tank just before spraying is started. 



The egg masses may be killed with an application of creosote in July soon after 

 the eggs are laid, but inasmuch as many egg masses are deposited on leaves and 

 small twigs this method of control is not so efficient as spraying. 



Birds and parasitic insects attack the satin moth and do much to hold it in 

 check. 



Britton, W. E. Conn. State Ent. Rpt. 32:415-416. 1933. 



Britton, W. E. Conn. State Ent. Rpt. 36: 361-364. 1937. 



Burgess, A. F. U. S. Dept. Agr. Dept. Circ. 167. 1921. 



Burgess, A. P., and Crossman, S. S. U. S. Dept. Agr. Bui. 1469. 1927. 



Collins, C. W., and Hood, C. E. U. S. Dept. Agr. Circ. 189. 1931. 



Glendenning, R. Can. Dept. Agr. Pamphlet 50, N. S., 1932. 



Saddled Prominent 



Heterocampa guttivitta Walk. 



This insect, sometimes called the antlered maple worm because of the antler- 

 like horns on the young caterpillars, is a native species generally distributed 

 throughout the northeastern United States and eastern Canada. The natural 

 enemies of this insect keep it under control for the most part, but occasionally it 

 becomes very abundant and may defoliate considerable areas of hardwoods. 

 The foliage of beech and sugar maple is preferred, but oak, birch, apple, and other 

 deciduous hardwoods are also attacked. The insect is an enemy of woodland 

 trees rather than of isolated shade trees in cities or parks, and generally stands of 

 trees on hillsides are more severely attacked than those in the lowlands. 



Description. The female moths have a wingspread of about 2 inches. They 

 are olive-green or greenish-brown flecked with splotches of creamy-white and 

 black. The males are slighth- smaller than the females and generally' darker in 

 color. 



The tiny eggs are circular, pale green in color, and laid separately on the leaves. 



The newly hatched caterpillars have antlerlike horns on the top of the first 

 body segment just behind the head. Other horns, less prominent, are also found 

 along the bodj'. The horns disappear after the caterpillar molts the first time. 



