320 OHIO EXPERIMENT STATION: BULLETIN 332 



A. glutinosa Willd. ; willows, Salix caprea L., S. viminalis L., S. 

 purpurea L., S. triandra L. ; poplar, Populus alba L. ; birch, Betula 

 sp. Jack (1897) states that in America all the native willows 

 except the slender-stemmed species are subject to attack. This is 

 confirmed by C. S. Sargent, Director of the Arnold Arboritum at 

 Cambridge, Mass. Of the imported willows the following have 

 been observed injured in the Arnold Arboritum: Salix alba L., 

 S, fragilis L., S. bablyonica Towm., S. pentandra Linn." 



The following species of poplars are also recorded as host 

 plants: Populus balsamifera L., P. deltoides Marsh., P. alba L. 

 Schoene (1907a) records the following species of willows as host 

 plants : Salix lucida Muhl., S. caprea L., S. cordata Muhl., S. sericea 

 Marsh, S. alba L., S. amygdaloides Anders. In addition two species 

 of birch are known to have been injured, Betula pumila L. and B. 

 nigra L." 



Distribution. This beetle is well-known in Europe and is widely 

 distributed over the northern and eastern section of the United 

 States. 



Control. — Doctor Matheson found that treating the trunks of 

 the trees with carbolineum avenarius is a safe and reliable remedy. 

 The liquid is taken in a small receptacle and the workman dips a 

 bit of cotton waste into the liquid and bathes the trunk of the tree. 

 The work should be one during the latter part of March or the first 

 week of April. It is preferable that the work be done on a warm 

 day since the carbolineum spreads better under such conditions. 



THE HICKORY BAEK BEETLE 



(Scolytus quadiispinosus Say) 



Description. — The hickory bark borer in the adult stage is a 

 tiny, dark-brown beetle about one-fifth of an inch in length. 



However, neither the larvae nor adults are often seen unless 

 special search is made by cutting into a dead or dymg hickory tree. 

 Usually when a hickory tree is dying and the trunk is seen to have 

 numerous, small, round holes in it, the work is that of this beetle. 

 (See Plate LXVI, Fig. 1.) 



Life history, habits and injury. — Doctor Felt summarizes the 

 life history of this species as follows: "The beetles appear from 

 the last of June to the last of July and may be found in New York 

 State up to the middle of August. They bore through young twigs, 

 terminal buds and green nuts, evidently for food, and in this man- 

 ner they frequently cause the wilting of leaves and the death of 

 twigs. They attack the bark of the trunk and the larger branches 



