TWO LEAFHOPPERS INJURIOUS TO APPLE NURSERY STOCK. 



Fig. 1. — Distribution of the apple leafhopper (Empoasca mali) in 

 the United States. 



points in the Province 01 Ontario, from Mexico, Porto Kico, and Cor 

 rientes, Argentina. In the United States this species is widely dis 

 seminated, doubtless 

 due to the variety and 

 abundance of its host 

 plants. From speci- 

 mens in the collection 

 of the United States 

 National Museum, 

 and from the collec- 

 tion, correspondence, 

 and notes of the Bu- 

 reau of Entomology, 

 it appears to be pres- 

 ent in almost every 

 State in the Union. 

 (See fig. 1.) It is found in greatest abundance throughout the east- 

 ern humid area of the Upper Austral Zone. 



FOOD PLANTS. 



The food plants of Empoasca mali (Le B.) are very numerous and 

 varied. In nurseries this insect prefers apple but it also feeds in 

 great abundance on Norway maple and various oaks. Among field 

 crops it is partial to alfalfa, clover, potato, and beets, in about the 

 order named. 



A list of all host plants reported, upon the majority of which the 

 writer has noted this insect feeding, follows: 



Acer negundo, box-elder. 



Acer platanoides, Norway maple. 



Alihea rosea, hollyhock 



Amygdalus persica, peach. 



Apium graveolens, celery. 



Avena sativa, oats. 



Beta vulgaris, beets. 



Betula sp., birch. 



Cannabis sativa, hemp. 



Castaneasp., chestnut. 



Corylus americana, hazelnut. 



Crataegus sp., hawthorn. 



Cydonia oblonga, quince. 



Dahlias^)., dahlia. 



Gramineae, grasses. 



Hamamelis virginiana, witch-hazel. 



Hicoria pecan, pecan. 



Juglans nigra, black walnut. 



Juglans sp., walnut. 



Medicago sativa, alfalfa. 



Phaseolus vulgaris, beans. 



Populus sp., poplar. 



Prunus virgianiana, choke-cherry. 



Prunus pissardi, purple-leaved plum. 



Prunus spp., cherries and plums. 



Pyrus baccata, Siberian crab. 



Pyrus communis, pear. 



Pyrus malus, apple. 



Quercus spp., oaks. 



Rheum rhaponticum, rhubarb. 



Rhus cotinus, smoke-tree. 



Ribes oxyacanthoides, gooseberry. 



Ribes rubrum, currant. 



Rubus spp., blackberry and raspberry. 



Rosa spp., roses. 



Secale cereale, rye. 



Solanum tuberosum, potato. 



Sorbus americana, mountain ash. 



Sorghum sp., sorghum. 



Syringasip., lilac. 



Tilia americana, American linden. 



Trifolium sp., clover. 



TJlmus americana, American elm. 



Viburnum sp., snowball. 



Ftospp., grapes. 

 Zea sp., corn. 



