SPRAYING EXPERIMiCNTS AND APPLK DISEASES. 7 



used. Up to June 3 no difference could be observed between 

 tihe foliage on the trees on this plot and that on those which had 

 been sprayed with lime-sulphur, but shortly after the second 

 application of the spray very evident injury began to appear. 



This injury was in the form of spotting and more or less 

 browning of the margins of the leaves and continued to develop 

 slowly till the time of the third application on June 24. After 

 the third application this spray injury developed very rapidly 

 and became quite severe. On July 7, 75 to 90 per cent of 

 the leaves on all of the trees on this plot were spotted or burned 

 at the margins, or both, many of tliem being badly injured. 

 Much yellowing and leaf drop showed at this time. The 

 specimens shown in Fig. i were collected on this date. 

 The yellowing and falling of the leaves continued for over a 

 month afterwards and conditions on July 15 were recorded as 

 worse than on July 7, the ground being nearly covered with 

 fallen leaves at this time. As a result of this leaf fall the 

 ^'Soluble sulphur" plot presented a marked contrast to the other 

 fungicide plots when viewed at a distance. It could be located 

 readily on account of the sparse condition O'f the foliage. 



"Soluble sulphur" appeared to be fully equal to standard dilu- 

 tion lime-sulphur in controlling scab on the leaves. 



Plot 6, sprayed with "Atomic sulphur" showed nothing on 

 the foliage throughout the season which could be definitely 

 classed as spray injury, although an occasional brown spot was 

 observed on the leaves. With regard to scab control it equalled 

 or exceeded all others except the bordeaux plot. 



Plot 7, unsprayed check. Scab on this, like the sprayed plots, 

 did not appear on the leaves till about June 10, or midway be- 

 tween the dates of the second and third applications, but from 

 then on it developed very rapidly on both foliage and fruit. 

 It was recorded as very common and severe, especially on some 

 trees, on July 7 and 15, and nearly every leaf was reported as 

 affected on August 4. Nothing like what has been classed as 

 spray injury on the other plots was observed on the check, but 

 frost injury was noted on this as well as on the others early in 

 the season. 



Plot 8, sprayed with one pound of dry arsenate of lead in 

 50 gallons of water. Throughout the season it was plainly 



