Walter Ritchie 341 



out before the end of June of each year, so as to be completed before 

 the beetles begin to emerge. 



As soon as the presence of adults is indicated by the cutting of the 

 leaves of the host plants, steps should at once be taken to seek out and 

 collect as many of them as possible. These should be looked for, in 

 Scotland, between mid July and the end of August. 



If carried out, these two measures will ensure the destruction of a 

 large percentage of the surviving larvae and beetles each year, so that 

 the damage will be reduced to a minimum. 



In the case of a few trees, e.g. park trees, oviposition may be largely 

 prevented by ensheathing the lowermost portion of their stems, say, for 

 a foot and a half above the level of the ground with netting of a close 

 mesh, or by coating them with some deterrent substance or wash which 

 would prevent the beetles from laying on them. A repellant wash, such 

 as that mentioned in Mr R. N. Chrystal's paper (18) on the "Poplar 

 Borer," Saperda calcarata Say, might prove useful. The formula is — 



In six gallons of saturated solution of washing-soda dissolve one gallon of soft- 

 soap, add one pint of carbolic acid, mix thoroughly; slack enough lime in four 

 gallons of water, so that when added a thick whitewash will result, then add one 

 half-pound of Paris green ; mix thoroughly. 



Natural Enemies. 



The larva of S. carcharias is parasitised by an Ichneumonid larva. 

 The Saperda larva is attacked while boring the horizontal portion of its 

 gallery. One parasitic larva is found on each host larva. The cocoon 

 spun by the former prior to pupation, may be discovered in the portion 

 of the tunnel which the latter had completed before its death. 



From the comparatively small number of cocoons found, it did not 

 appear that this Ichneumon was very common in this area. Throughout 

 the investigations no instances of fungus-parasitism were observed 

 either on adults or larvae. In the province of Gerona, Spain (17), however, 

 an Entomophagous fungus has recently been found destroying both 

 adults and larvae of this Longicorn. 



In a note on the "Planting of poplars at Kininvie," Banffshire, 

 Scotland, published in the Transactions of the Royal Scottish Arbori- 

 cultural Society, of January, 1919, attention is drawn to the fact, that 

 the cultivation of poplars for economic use has been very much neglected 

 in this country in the past, and that the question of their cultivation is 

 as yet in the experimental stage. It is certain, however, once the 

 possibilities of the various species as economic forest trees have been 



