20:4 REPortT oF THE BOTANICAL DEPARTMENT OF THE 
showing blight and there was evidently more of it on the check 
rows than on the adjacent rows treated with paris green 
in water or on those treated with paris green in lime water. 
Series IV and V, sprayed with bordeaux, were not affected. 
On August 10 the check rows were seriously affected and the 
superiority of the rows treated with paris green was pronounced. 
On September 8 the check rows were nearly dead from blight, 
while the rows receiving paris green (Series II and III) still re- 
tained about one-half their foliage and the rows receiving bor- 
deaux (Series [IV and V) were in almost full foliage. It was 
very plain that the application of paris green had materially 
checked the blight but that the bordeaux lad been much more 
effective. The rows treated with paris green in water and those 
treated with paris green in lime water were equally blighted and 
there was no apparent difference between the rows treated with 
bordeaux and paris green and those treated with bordeaux 
alone. 
On September 16, Rows 14, 15, 16, 17 and 18 were photo 
graphed (See plate XVII).*? Row 14 (bordeaux and paris green) 
and Row 15 (bordeaux only) were about equal. Two-thirds 
of their foliage was still green. On Row 16 (check) the plants 
were all dead and dry over at least one-half the length of the 
row.’? Row 17 (paris green in water) and Row 18 (paris green 
in lime water) were about equal. Both were superior to the 
check, but markedly inferior to the bordeaux rows Nos. 14 and 
15. Most of the plants were still alive with tufts of green 
leaves at their tips. 
Effect on the yield.—The potatoes were dug by hand on Oc- 
tober 17 and 18. The product of each row was carefully sorted 
into two sizes, marketable and unmarketable, and the weight of 
each size taken. All tubers showing the least sign of rot were 
rejected. On all of the rows there was an occasional rotten 
tuber, but they were so few that no record of their weight was 
kept. Moreover, on Series I, II and III most of the affected 
122Jn order to bring out better the condition of the foliage on the different 
rows a white back-ground was made by sifting air-slacked lime over the 
ground under the plants. 
123Row 16 fell in a dead-furrow and for that reason its yield was left out 
of consideration in making up the yields of the different series. However 
this had no bearing on the blighting of the tops. Plants are neither more 
nor less subject the late blight for being in a dead-furrow. 
