24 



FOREST ENTOMOLOGY. 



Eriophyes avellan^e (Nal.) 



The nut-tree mite is found in filbert and cob-nut plantations. The 

 swollen and deformed buds can easily be recognised before the devel- 

 opment of the leaves ; and they are also afterwards conspicuous, as 

 shown in the accompanying illustration (fig. 23). 



The species living in buds of hazel lend themselves more or less to 

 periodical examination throughout the whole of the year. Having 

 examined them in February from young hazel plants, I found the 



enlarged buds, more especially the infested 

 terminal bud, conspicuous as globular balls 

 about \ inch in diameter. ^Numerous mites 

 were found in all portions of the bud, 

 from the outer scales to the centre. They 

 were discovered in all stages viz., eggs, 

 larva?, nymphs, and perfect mites. This 

 species of mite is larger than the species 

 found on the black currant. The eggs are 

 whitish, smooth, and oval. The nymph is 

 approximately about one-half or one-third 

 the size of the perfect mite, and the four 

 legs are stretched out in the direction of 

 the mouth. 



An examination of the swollen buds 

 during May, when the leaves were half 

 developed, showed the infested buds 

 to be tenanted in all parts, and a 

 few mites crawling along the leaf- stalks. 

 They were in all stages viz., full - grown mites, nymphs, and 



Fig. 23. Abortive swollen bails 

 caused by Eriophyes avellanae 

 on hazel. 



eggs. 



In July another examination was made, and it was found that the 

 mites were chiefly in the interior portion of the swollen buds. There 

 were a few on the leaf-stalk and on the portion of the stem adjacent 

 to the infested buds. At this time the swollen buds were quite half 

 an inch in diameter, and the young buds for the forthcoming season 

 were just formed. 



