PROTECTING TREES FROM CANKER WORMS. 21 



vation. After flowering they were put under the stage and kept 

 either too wet or too dry. 



President Strong introduced the subject of protecting trees from 

 canlier worms, having received a circular describing Mathew's 

 Tree Protector. A model of the contrivance, which consists of a 

 zinc trough with a roof of the same material, was also shown. 

 The only noveltj- appeared to be in the oil, which, it is claimed, 

 not only destroys the worm mechanically, filling up the breathing 

 pores like ordinary oil, but is also poisonous, and, the outside of 

 the trough being covered with oil by capillary attraction, the worms 

 are killed in the attempt to crawl over it, and hence the trough is 

 never filled with their dead bodies. 



Benjamin P. Ware said he had had some experience in protecting 

 trees ; the objection to this contrivance is the expense, twelve 

 cents per inch of internal diameter, or for trees twenty inches in 

 diameter, two dollars and forty cents per tree. Unless the protec- 

 tors are carefully looked to they are ineflJ'ectual ; leaves blow in, 

 spiders spin webs across, thus making bridges over which the 

 worms travel. It would be unwise to use this protector, when 

 with the same or a little more care they can be protected with 

 tarred paper and printers' ink for ten cents per tree, as was done 

 bj^ Joseph S. Howe of Methuen, who kept an exact account of all 

 expenses of thus protecting a large orchard. The tarred paper will 

 last two years ; the ink should be renewed in from one to two 

 weeks, or in very dry weather twice a week. It is very important 

 to protect the trees when the insects first begin to run, which 

 always happens with the first frost in autumn, and never before. 

 The insects will deposit their eggs on the bark below the ink, and 

 it should therefore be applied when the eggs first hatch, to prevent 

 the larvjE from ascending. 



Edwin W. Buswell said the trees would soon outgrow these pro- 

 tectors, and then the cultivator would be subjected to the expense 

 of removing them to smaller trees and providing new ones for the 

 larger trees. He spoke with approval of those used by John G. 

 Barker, when gardener to G. G. Hubbard of Cambridge, w^hich 

 consisted of a square box, about a foot high, with a zinc trough 

 covered by a roof on the outside, the space between the box and 

 tree Jieing filled with coal ashes. The oil used was crude petro- 

 leum. 



