86 INSECTS AFFECTING VEGETATION 



The Giant Root Borer. Besides the crown borer, the blackberry 

 also harbors in its roots an enormous beetle larva, between two and 

 three inches in length, white in color, with strongly-marked con- 

 strictions at the segments, a distinct enlargement anteriorly, and a 

 small, smooth, brown head, with stout, dark-brown jaw r s. The parent 

 of this larva is a long-horn beetle. 



The pupa is formed in June or early in July, and the beetle 

 makes its appearance at about the middle of the latter month. It 

 is rarely seen, even where not uncommon, and flies principally at 

 night. Fortunately this borer is comparatively scarce; but where 

 it does occur, signs of its work are readily observable. It lives in the 

 large, woody portions of the main root, in which it bores huge chan- 

 nels, and the sudden dying off of several canes in a hill is a certain 

 indication of its presence. Rarely only a single cane will be affected, 

 and then if a crown borer is not found, the presence of this insect 

 in the main root is almost certain. 



As with the preceding, the remedy is mechanical. Whenever 

 signs of its presence are noted, it should be at once sought for and 

 destroyed. It is more common in old, carelessly-kept fields and, 

 where numerous in such places, it will be better to grub out and 

 burn all suspected stocks, and replace them by new plants. This 

 should be done before the middle of June, to prevent the maturing 

 of the beetles. 



The Raspberry-root Borer, or the Blackberry '-croivn Borer. The 

 parents of this borer are of the clear-winged moths belonging to the 

 family Sesiidce and the species is a near relative of those producing 

 the peach and squash borers. In appearance in the field it is not 

 unlike a wasp or hornet, and may be readily mistaken for one or the 

 other by a casual observer. 



The body of the insect is rather more than half an inch in 

 length, black, the thorax with narrow yellow markings, the abdomen 

 with six distinct yellow rings and a tuft of yellow hair near the base. 

 The legs are also clothed with yellow hair and scales. The wings 

 expand about one inch, are narrow, transparent, and with a bronze- 

 brown margin. The primaries or fore-wings have also a narrow, 

 transverse, brown band about one-third from tip. 



The moths make their appearance in the fields late in August 

 and early in September, and soon after begin ovipositing. A single 

 egg only is laid on the cane, near the surface of the ground, or even 

 a little below. The young larva, when hatched, immediately eats 

 through the bark and begins work at the base of the stalk, where it 

 joins the crown or main root, confining itself largely to the sap- 

 wood. The young larva is yellowish white, usually with a faint red- 

 dish tinge. It attains a length of from one-quarter to one-third of 

 an inch during the fall, and has at that time eaten about half 

 through the cane, sometimes entering the pith and boring up into 

 the stem for a short distance. Usually, at the seat of injury there 

 is a morbid enlargement of the cane, and this gives room for the 

 pupal cell. The pupa is small in proportion to the full-grown larva, 



