Five-year Tests with Summer Treatments 
The data presented in table 1 summarize the results of five years of 
experiment with pruming and with Bordeaux mixture (Corona), Koppers flotation sul- 
‘phur, Koloform, and Kolodust,. 
Table 1.--Results in disease control in nursery elms obtained from 5 consecutive 
seasons of pruning, spraying, dusting, and pruning combined with 
spraying or dusting. 
————— 
No. of trees Difference in Percentage of 
Plot numbers No, of trees contracting favor of (+) or control (+) 
and originally disease in against (-) or lack of 
treatments used present 5 years treatment _ control (-)* 
Piot IIT 
Check 300 nite 
Pruning 500 7 + 26 + 78,8 
Bordeaux spray 300 38 - 5 - 15.2 
.Bordeaux + pruning 300 29 + 4 ied 
Plot IV 
~ Check — 500 7 
Pruning 500 6 ae + 14.35 
Koloform spray 500 9 - 2 - 28.6 
Koloform + pruning a HOD 13 - 6 - 85.7 
Plot VII 
Check 711. 151 
Bordeaux spray 4°74 113 - 18%** - 11.9 
Flotation sulphur 
spray 474 116 — 20%% ~ 15.2 
Plot VIII 
Check 400 64 
Pruning 400 67 - 3 - 5,0 
Kolodust 400 46 + 18 + 28.1 
Kolodust + pruning 400 535 + 31 + 50.0 
Plot IX=L 
Check 347 113 
Koloform spray 547 142 - 29 = 2567 
* Percentage of control obtained as follows: Treatment difference (col. 4) x i900, 
Disease in check (col, 3) 
**k Calculated on the basis of 711 trees in each treatment. 
=Gee 
