J2 NEW YORK STATE MUSEUM 



of the inner bark, evidenced by a marked brownish discoloration, 

 was apparent and ten days later, namely March 12th, there was an 

 evident invasion of the compound, the inner bark and the outer 

 portion of the sap wood being dark brown. At this time the untreated 

 upper portion of the limb was green and normal, there being an 

 abundance of sap in the inner bark and the sap wood, though there 

 was some drying back at the very tip of the small branches. With 

 a knife the outer bark was then carefully shaved from the entire stick 

 in order to remove all the oily portion and thus show more clearly 

 the condition of the inner bark and sapwood. This uncovered 

 a series of plainly discolored areas having a transverse diameter of 

 one-half to three-fourths of an inch, a length of an inch or more and 

 extending frequently through the inner bark and into the sapwood. 

 This shows clearly that under certain conditions an oily compound 

 may penetrate the outer bark, pass through the inner bark and 

 invade the sapwood. It is not claimed that this limb was under 

 normal conditions and that therefore this result would invariably 

 follow when such treatment was given to trees standing in the open. 



This test was supplemented by applications March 8th to healthy 

 forest trees standing in a location where there was no reason to 

 suspect that unnatural conditions might influence the outcome in 

 the slightest. The material was applied rather thickly from near 

 the ground to a height of about 6 feet between 3.30 and 5.30 p.m. 

 of a moderately warm, clear day, the sap in the sugar maples flowing 

 abundantly. All the trees were so well protected by the surrounding 

 growth that there could be no unusual exposure of trunk or branches 

 to the sun. 



Tree 1 was a sugar maple with a trunk diameter of ii inches and 

 a height of approximately 12 feet. On May 29th the bark was 

 moist, greasy, and the leaves full size, though beginning to dry and 

 presenting an unhealthy, brownish green appearance. This tree 

 stood in a moderately open place so that the foliage received con- 

 siderable light. The inner bark showed a brown discoloration in its 

 outer layers and below a brownish green, unhealthy appearance. 

 June 28th the tree was mostly dead, the inner bark was light brown 

 and somewhat sappy. On November 10th the tree was dead save for 

 some evidences of life at the very base and below the treated part. 

 The oiled portion of the bark was brown and showed a distinct, 

 dark line just beneath the surface. The tree had been entered 

 by Ambrosia beetles, indicating an earlier, unhealthy condition. 



Tree 2 was a sugar maple with a trunk diameter of 1 J inches and a 

 height of 12 feet. The bark was lightly scored with a knife just 



