BULLETIN" 256, U. S. DEPARTMENT OF AGRICULTURE. 



Fig. 1.— Orange 

 bud injured 

 by katydids. 

 (Original.) 



is so large that a day's feeding by a single individual may mean the 

 destruction of several small oranges. Once an orange is attacked it 

 is invariably rendered unfit for sale, and therefore usually left on the 

 ground in the field at picking time. 



The young katydids are on the trees and actively feeding at about 

 the time the latter are beginning to lose their petals, and the injury 

 usually begins at this stage. The insect will sometimes 

 attack the blossom buds, generally gnawing a hole 

 through the petals to reach the pistil and ovary, these 

 organs often being destroyed in a considerable number 

 of blossoms (figs. 1, 2). The petals themselves have 

 apparently but little attraction for the insect. 



Whenever as many as 15 or 20 of the nymphs are 

 found on a tree, the injury to the immature fruits 

 becomes quite noticeable and a quantity badly chewed 

 will be found on the ground (PI. I, fig. 1). The injured 

 oranges usually have been more than one-third destroyed 

 or have received one or more holes large enough to 

 admit the head and thorax of the slender katydid nymphs, such 

 holes often extending entirely through the oranges. Many other 

 oranges which have been two-thirds or more eaten away will be 

 indicated by the portions remaining on the trees. The oranges 

 which have been only slightly chewed when small and those which 

 receive the injury after they are considerably grown and have "set" 

 firmly to the tree remain to ripen only to be "culled" out either at 

 picking time or in the packing-house. At picking time 

 many of these damaged fruits are conspicuous owing to 

 the clean-cut circular holes in the rind, which vary from 

 the size of a dime to about that of a silver dollar (PI. I, 

 fig. 2; PI. II, fig. 1). The insects have the habit, how- 

 ever, of chewing into the larger fruits from the side 

 toward the tree trunk, seeking the shade and also pro- 

 tection from birds, and the injury may not then be noted 

 until the fruit is picked. The holes in the more mature 

 fruits, as in the very young ones, are often deep, extend- 

 ing through the rind and rag, well into the pulp. Many 

 oranges are split wide open as the result of katydid 

 injury inflicted when they were only about one-fourth 

 matured, due to inability to expand along the dried 

 edges to accommodate growth (PI. II, fig. 2). All oranges which 

 have been attacked after the crop has thoroughly set mature with 

 the sound fruit, on the trees, and although edible they must be 

 considered a dead loss, since they are unfit for shipment. 



Examination in the orchards of hundreds of boxes of oranges 

 throughout the San Joaquin Valley during the picking seasons of 



Fig. 2.— Young 

 Navel orange 

 from which 

 the pistil re- 

 mains and 

 part of the 

 fruit has been 

 eaten by 

 katydids. 

 (Original.) 



