THE AMERICAN BOTANIST 



151 



snakeroot as the state flower of Illinois when its connection 

 with history is better known. 



Tree Doctoring for Insects. — In country districts, one 

 may still find tree doctors who go about from door to 

 door offering to cure sick trees by the use of iron and 

 sulphur. The iron is supplied by driving a handful of 

 nails into the trunk of the tree and the sulphur added by 

 boring a hole in the tree and putting in the sulphur in 

 powdered form. To those who still dose themselves with 

 sulphur and iron tonics, this treatment of the trees seems 

 the most rational thing in the world, but the botanist 

 scouts the idea that it can be of any use whatever. A 

 writer in Science, however, advocates something similar 

 for preventing the attacks of insects. Having specimens 

 of Spanish broom that were badly infested with the cottony 

 cushion scale, he bored holes in the trunks and filled them 

 with crystals of cyanide of potassium, carefully plugging 

 up the openings. In a very short time all the scale insects 

 dropped from the trees, dead. Cyanide of potassium, it 

 may be said, is one of the deadliest poisons known and the 

 question then arose as to whether similar treatment of 

 trees with edible fruits would render the fruits harmful. 

 Accordingly peach and orange trees were tried without 

 apparent ill effects. H. A. Surface, however, who is State 

 Zoologist of Pennsylvania, reports that the good effect?' 

 of this treatment are only temporary and the bad effects 

 very permanent inasmuch as trees treated with cyanide 

 of potassium are ultimately killed by the treatment. He 

 cites scores of orchards that have been killed in this way. 

 The idea of "vaccinating" trees against the insects seems 

 to have originated in Pennsylvania, but in spite of the 

 warnings of scientific men, the fakirs are making money 

 in the business. 



