LIME AND DENDROLENE. 



135 



lower edge in such a way as to form a trough and then apply 

 the lime upon this. If this band of paper is placed at a 

 considerable height, it may prevent many of the disagreeable 

 accidents which otherwise frequently happen. Thus far we 

 have had no experience in applying the lime in this manner. 



Other Uses for Insect Lime, 

 Dr. John B. Smith, entomologist of the New Jersey Ex- 

 periment Station, in a paper read by him as president of the 

 Association of Official Economic Entomologists at a meet- 

 ing of that society held Aug. 27, 1895, in connection with 

 the meeting at Springfield of the American Association 

 for the Advancement of Science, gave the results of his 

 experiments with raupenleim and a similar material, **den- 

 drolene."* Dendrolene was invented by Prof. F. L. Nason 

 of New Brunswick, who, at the request of Dr. Smith, experi- 

 mented with a view of obtaining a material of home manu- 

 facture possessing the insecticide and protective properties 

 of the raupenleim. According to Dr. Smith, raupenleim and 

 dendrolene are both crude petroleum products, though the 

 raupenleim has some admixture of a substance resembling tar 

 in color and odor ; but in both cases the base is, or seems to 

 be, a very crude or impure vaseline, which has the appearance 

 of the base of such lubricating mixtures as wheel-grease. 

 Dr. Smith has used both substances on trees to prevent 

 both the entrance and the emergence of certain tree borers. 

 So far he has seen no injury to the tree resulting from the 

 use of either material, even when large areas of bark were 

 covered. While the raupenleim seemed more eflective 

 against borers, the dendrolene remained soft longer, making, 

 as Dr. Smith says, *'a perfect barrier against insects 

 attempting to cross it." He also says that such materials 

 may be employed against scale insects on comparatively 

 small trees where they cover only the trunks and larger 

 branches, and where even a thin coating applied with a brush 

 early in the season before the eggs have hatched or before 

 reproduction has begun in the case of the viviparous species, 

 will absolutely prevent the emergence of young. The appli- 



* See Bulletin of Experiment Station, New Jersey Agricultural College, No. Ill, 

 Sept. 16, 1895. 



