22 MISC. PUBLICATION 7 4, U. S. DEPT. OF AGRICULTURE 



THE PINE NEEDLE MINER AND OTHER CONIFEROUS LEAF MINERS 



Recurvaria spp. 



These leaf miners are often important pests of coniferous trees, 

 especially pines, in the forests of the Pacific coast region. The genus 

 is widespread throughout the United States and contains many 

 species attacking other genera of coniferous trees besides pines. In 

 the Yosemite National Park, Calif., great areas of lodgepole pine 

 were killed by Recurvaria milleri Busck (&£). 



THE SATIN MOTH 



Stilpnotia salicis L. 



The satin moth, a recently introduced insect, has become estab- 

 lished in the New England States. It has increased in abundance 

 and spread with great rapidity. The caterpillars prefer poplar and 

 willow, but will feed to a certain extent on other species of deciduous 

 trees, chiefly oaks. The principal damage caused by the insect is 

 the complete defoliation of many poplars and willows {IS), 



THE LARCH SAWFLY 



Nematus erichsonii Htg. 



Larch in the Northeastern States and in the Lake States is period- 

 ically defoliated by the larvae of the larch sawfly. Several of these 

 great outbreaks occuring since 1880 have practically wiped out all 

 the mature larch in the northeastern part of the United States and 

 southeastern Canada. 



The western larch in Idaho is similarly attacked by two related 

 sawflies (36, S3). 



THE LODGEPOLE SAWFLY 



Neodiprion sp. 



The lodgepole sawfly occasionally kills lodgepole pine in Idaho, 

 Montana, and Wyoming. The most recent destructive outbreak oc- 

 curred in connection with the outbreak of the lodgepole needle tier 

 mentioned under that species. 



OTHER SAWFLIES 



Neodiprion spp. 



Jack pine in Minnesota was severely defoliated in 1923 and 1924 by 

 sawfly larvae of this genus. Neodiprion banksianae Ron. and another 

 species near N. scutellaris Roh. were found attacking western yellow 

 pine in Idaho in 1922 and young lodgepole pine in West Yellowstone, 

 Mont., in 1924 and 1925. 



During a widespread outbreak in 1926, which extended from Massa- 

 chusetts to Louisiana, pines in Mecklenburg County, southern Vir- 

 ginia, suffered a severe defoliation, a large percentage of the pines in 

 the county being attacked. 



An outbreak of N. excitans Roh. severely defoliated pines in 

 Montgomery County, eastern Texas, in 1919 and was reported as 

 doing serious damage to pine timber. 



