PROTECTION FROM INJURY BY THE JAPANESE BEETLE 3 



FRUIT AND ORNAMENTAL PLANTS ATTACKED 



The Japanese beetle feeds on a large number of plants. It has a 

 marked preference for the foliage and fruit of apple, peach, plum, 

 quince, cherry, raspberry, and blueberry, and the foliage of grapes. 

 It rarely injures dewberries and the Black Diamond variety of black- 

 berries but occasionally attacks certain other varieties of black- 

 berries. Pears are rarely attacked. Among the shade trees, it is 

 especially fond of linden, chestnut, horsechestnut, sassafras, and elm. 

 Other trees such as buttonwood, willow, birch, Lombardy poplar, 

 Norway maple, and certain varieties of oak are occasionally attacked. 

 The beetle rarely feeds on the foliage of most maples, ash, magnolia, 

 mulberry, sweet gum, sour gum, tulip tree, hackberry, and beech. 



Figure 3.— Sprayed and unsprayed apple trees in an orchard near Moorestown, NJ. Note the new 

 growth on the tree defoliated by feeding of the Japanese beetle. 



As a rule, conifers are untouched, although occasionally the needles 

 of larch and of bald cypress are injured. The beetle is likely to 

 injure such ornamentals as flowering cherry, flowering quince, 

 flowering peach, spirea, hawthorn, althea, rose, hibiscus, and Virginia 

 creeper. 



METHOD OF PROTECTING PLANTS 



It is possible to protect the foliage and fruit of many of these plants 

 by maintaining a deposit of spray residue on all portions of the plants 

 subject to attack, during the period when the beetles are flying. The 

 spray residue largely repels the beetle and prevents extensive feeding, 

 the protection being obtained primarily by making the plant non- 

 attractive rather than by poisoning the beetle. 



Diseased and poorly nourished plants are more susceptible to 

 attack than those in a healthy condition. It is practically impossible 

 to prevent the beetles from becoming established in orchards where 

 brown rot and similar diseases are present. Orchards should be 



