34 



SULPHUR AS AN INSECTICIDE AND FUNGICIDE. 



The fumes of sulphur are well known to be destructive to both 

 plant and animal life, but in its crystalline or "brimstone" form it is 

 wholly insoluble and therefore inactive as an agent of destruction to 

 either plants or animals. 



Almost every season the report comes to us through the agricultu- 

 ral journals or from other sources, of experiments made with the in- 

 soluble form of sulphur for the prevention of insect injuries to the fo- 

 liage of fruit or other trees. 



The most common method of application is to insert the sulphur 

 in holes bored in the trunks of the trees, with the idea that it will be 

 dissolved by the sap of the tree and carried to the foliage or fruit in 

 such quantities as to render it offensive to insects. No longer ago 

 than the past spring it was reported that the Forester of the city of 

 Boston had bored large holes in many of the large elms within the 

 city limits, and had inserted sulphur to prevent the elm beetle from 

 injuring the foliage. 



Now, it has been found upon cutting down trees that have been 

 plugged with sulphur that the material remains unchanged for many 

 years, and from the very nature of these conditions it is absurd to 

 suppose any good result can come from this practice. We have in 

 the Botanic Museum a specimen of a tree cut down and split open, in 

 which is found a mass of sulpiiur wholly unchanged. It had been 

 inserted m an inch augur hole twenty-five years before the tree was 

 cut down. See Hovey's Magazine of Hort. No. CCLXXX, P. 182. 



It is hoped that at the close of the coining season some of the trees 

 thus treated by the city of Boston may be cut down and examined, 

 and the results made public, for, while we spend so much time in 

 trying to prevent injury to our trees from borers, we certainly ought 

 not to make holes in them many times larger than those of any 

 known species of insect borers. 



While we would discourage anything that may be of such serious 

 injury to the tree as the above, the suggestion comes to us that sul- 

 phur in a soluble form may be introduced into a tree in sufficient 

 quantity to affect fungus growths which cause the rusts, blights, 

 mildews, etc. 



In order to test this matter, a lot of rose bushes of large size, 

 which were badly mildewed, were selected and the following solu- 

 tions inserted by boring a hole with a small gimlet and forcing 

 the liquid into the opening with a medicine dropping tube. 



