DKSTKoyiNc; I'liE lU.ACK KNOT. 



Tlie results of spra3nng" for the destruction of the Bhick Knot or 

 wart, are shown in the following tables : 



*S prayed 189.5. 



The trees were sprayed witli copper sulphate solution, Bordeaux 

 mixture and aninioniacal carbonate of copper. The knots were 

 painted with keiosene and mineral pigment during the summer, and 

 remoA'ed during the early part of winter. When found on small 

 twigs the knot and branch were removed, but when found on large 

 limbs or strong shoots the knots were sliced off and the wound painted 

 with lead and oil. This treatment has been given to sprayed and 

 unsprayed trees alike. By studying the above table, which shows 

 the results of the treatment on a row of Washington and Lombard 

 trees we find : 



1st. That the total number of knots has been steadily decreasing. 



"id. That the average number on the unspraj^ed trees has decreased 

 to one half the number in 18!) 1 , while on sprayed trees it has decreased 

 to -^ of the number found fonr years ago, or where one knot has 

 been destroyed by painting and cutting, twenty-six have been 

 destroyed by combining this treatment with spraying. 



In Dec, 1895, 88 plum trees, of bearing size including many 

 varieties were examined and the knots removed. These trees, with 

 the exception of two Wild Goose, one Pottawattamie and three 

 Japanese varieties, are all European plums. The young orchards 

 containing the Japanese and native pluins,having never been attacked 

 with knot, are not inclnded. 



