434 Agricultural Experiment Station, Ithaca, N. Y. 



among which may be mentioned, grafting and budding, when 

 there exists, as is often the case, a disparity in size or lack of 

 affinity between scion and stocli; and abrasions or wounds of any 

 kind made on the tree beneath the ground surface. 



" In the second instance the lack of harmony between root and 

 branch may be caused by an unseasonable loss of foliage, either 

 through severe summer pruning, or the killing of the young 

 growths by a late freeze. The means of transferring the moisture 

 absorbed by the roots being thus suddenly cut off, the sap cells in 

 the lower portion of the tree become congested, resulting in the 

 ruj>tures taat cause the formation of the callus knots, or tumors. 



" As to the remedy for these tumors, I have always found cnt- 

 ting them off quite effective if taken in time, and when the work 

 has been well done I have seldom seen a return of the knots; it 

 is well to cover the wounds thus made with grafting wax or any 

 substance that will answer the purpose of excluding the air with- 

 out injuring the tree. 



" From my present knowledge of root tumors I fail to see 

 where Mr. Smith's solution of bluestone remedy can be of much 

 benefit. Regarding the dead knots he found on trees previously 

 treated with this remedy, I may say I have frequently noticed 

 the same thing, as in many cases the tumors when partly rotten 

 became detached from the tree, often, however, leaving a canker 

 spot that later may endanger the life of the tree affected, if noir 

 attended to. 



" I have more commonly met with these tumors on peach, 

 plum and apple, but also occasionally on over thirty other spe- 

 cies of fruits, shade trees and evergreens." 



The conclusion of the whole matter, then, as we now under- 

 stand it, is that these root-galls are not the work of a parasite, 

 but are a malformation following some injury of the root or 

 some uncongenial condition in soil or treatment. The galls may 

 seriously interfere with the nutrition of the plant, in many cases 

 causing it to become weak and sickly. It is probable that the 

 trouble is not communicable, and that cutting off the gall averts 

 further trouble from that source. As a precautionary measure, 

 however, we much prefer to plant only trees with perfectly clean 

 and normal roots. 



