INJURIOUS TO C ABB ACE AND RE LATE I) CROPS 49 

 The Cahhace CuKcrLio 



Ccutorhynchus rajxv GyllcMihal 



One of the minor pests of cabbage, cauliflower, kale, radish 

 and horse-radish is a small ash-gray weevil about ^ inch in 

 length. This beetle is a native of Europe where it has nexer 

 attracted attention as an enemy of cultivated crops. It was 

 apparently introduced into America in New England about 

 the middle of the last century but is now generally distributed 

 throughout the northern states from New York to Virginia 

 westward to Nebraska and Colorado. It also occurs in Cali- 

 fornia. 



The insect hibernates in the adult condition and the WTcvils 

 appear in the field in early spring. They feed slightly on the 

 leaves and also puncture the stems of their food ])lants, eating 

 out a cavity as deep as they can reach with the beak. The 

 female deposits her eggs singly in similar punctures in the 

 stems. The tissue surrounding the egg-puncture becomes en- 

 larged, forming a noticeable scar. The egg is about -^5 inch 

 in length, oval and shining white. The eggs hatch in about a 

 week and the grubs, several of which may infest a single stem, 

 hollow out the contents, often causing the plants to turn 

 sickly and die. The full-grown grub is ^ to J inch in length, 

 milky white with a brownish head. The larvte become mature 

 in about three weeks, gnaw their way out of the stem and 

 enter the ground where at a depth of less than an inch they 

 transform to milky white pupve in oval earthen cells. The 

 beetles appear in about a week, or during the early part of 

 June in the District of Columbia, and feed for a time on the 

 stems and leaves of their food plants. Although the new brood 

 of beetles appears at this early date, there is apparently only 

 one generation annually. 



Larvit' of the cabbage curculio have been found in the stem 

 and crown of cabbage and cauliflower, the petioles of liorse- 



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