26 MISC. PUBLICATION 273, U.S. DEPT. OF AGRICULTURE 



Species of Megastigmus Hosts and distribution 



albifrons Wlkr Ponderosa pine. Arizona, California. 



lasiocarpae Crosby Alpine fir, Pacific silver fir. Colorado, Wash- 

 ington. 



milleri Milliron Grand fir, Shasta red fir. California, Canada 



(British Columbia). 



"piceae Rohw Blue spruce, Engelmann spruce, Colorado. 



Sitka spruce, California, Oregon. 



pxceae var. montana Milliron. Engelmann spruce. Montana. 



pinus Parfitt Pacific silver fir, grand fir, white fir, California 



red fir, Shasta red fir, Noble fir. California, 

 Oregon, Washington, Nevada, Colorado, 

 Idaho. 



rafni Hoffmeyer White fir, grand fir, California red fir, Shasta 



red fir. California, Colorado, Idaho, New 

 Mexico, Oregon. 



spermotrophus Wachtl Douglas-fir. Western U. S. and Canada. 



spermotrophus var. nigrodor- 



satus Milliron Bigcone spruce. California. 



tsugae Crosby Mountain hemlock. Oregon and Washington. 



OTHER TREE SEED INSECTS 



Nuts and acorns of various western hardwoods are frequently 

 infested by the curled white grubs of the nut and acorn weevils, 

 belonging to the genus Curculio. The adults are medium-sized, 

 yellow, brown, or nearly black weevils with robust bodies, long 

 legs, and prominent, slender, curved or nearly straight beaks. 

 The adults appear in the summer. With their beaks they gnaw 

 holes in the shells of new acorns or nuts and in these they place 

 their eggs. The larvae feed on the meat and destroy the seed. The 

 winter is passed in the larval stage, either within the acorn or 

 in the ground. Pupation occurs the next spring, and the adults 

 emerge in the summer. Several species of Curculio are found in 

 oak acorns in the Western States. The most common of which is 

 the filbert weevil Curculio uniformis (Lee), which is distributed 

 through New Mexico, Arizona, Utah, California, Oregon, and 

 Washington. 



The filbertworm (Melissopus latiferreanus (Wlsm.)), a small 

 white or pinkish caterpillar about 3 4 inch long, may be found 

 boring through oak acorns and galls, hazelnuts, filberts, chestnuts, 

 chinquapin, Catalina cherry, and various other fruits and nuts 

 throughout the United States. In the Pacific Northwest there is 

 one, and a partial second, generation a year. The larvae hibernate 

 in cocoons beneath or on the surface of the ground, or in the dam- 

 aged host. Emergence of adults seems to be synchronized with the 

 formation of nuts or acorns. 



The maple seed caterpillar (Proteoteras aesculana Riley) works 

 in the seeds of bigleaf maple, completely mining them out. 



The ash seed weevil (TJujsanocnemis sp.) is a small yellow 

 weevil y 8 inch long, which lays its eggs in a puncture on the young- 

 developing seeds of ash. The tiny larvae penetrate the seed without 



