38 
BULLETIN 828, U. S. DEPARTMENT OF AGRICULTURE. 
ments were June 19, 28, July 6, 13, 18, 28, August 3, 13, and 16. 
Table I gives the details as to the number of plants, kind and num- 
ber of treatments, and wilt records for each plat in the field, and figure 
10 shows graphically the relative effect of the various treatments 
as compared with the control plats. Photographs of plats Nos. 1, 6, 
and 11, taken August 25, 1916 (Pis. II and IV), show the appearance 
of the vines with all the applications of Bordeaux mixture and lead 
arsenate, with lead arsenate alone, and also without any treatment. 
Each stake shown in these photographs represents one case of wilt. 
in all cases the cucumbers were picked when about 6 inches in 
length. Xo new or special combinations of insecticides were used 
in this test, as the insect control, per se, is a matter left to the Bureau 
of Entomology. In the earlier tests, Bordeaux mixture with lead 
arsenate gave a better control than either mixture alone, so that 
2 pounds of lead arsenate paste were added to each 50 gallons of 
Bordeaux mixture used in this experiment. 
Table I. — Bacterial wilt record of the spray experiment in Field Ila at East Marion, 
Long Island, 1916. 
New cases 
3i wilt at different dates. 
Num- 
ber of 
plants 
at the 
start. 
Wilt for the 
season. 
Treatment. 
Plat 
No. 
July— 
August— 
Total. 
Per- 
cent- 
age. 
11 
18 29 
9 
15 23 
1 
2 
3 
4 
5 
6 
8 
9 
10 
11 
6 
7 
8 
3 
3 
1 
3 
9 
2 
11 
12 
21 
26 
8 
6 
5 
12 
32 
48 
19 
56 
50 
48 
52 
58 
21 
30 
36 
41 
51 
66 
25 
29 
12 
43 
33 
17 
24 
20 
26 
IS 
16 
11 
6 
14 
5 
6 
7 
15 
1 
4 
3 
2 
2 
8 
5 
248 
325 
230 
234 
227 
267 
268 
282 
231 
260 
264 
Ill 
103 
106 
131 
110 
60 
82 
90 
IIS 
134 
137 
Bordeaux mixture plus lead arsenate: 
32 
2-3-50-2, fir-^t two only . . . 
2-3-50-2, first onlv 
56 
2-3-50-2, all but first four 
2-3-50-2, all applications 
48 
22 
2-3-50-2, all but first. . . 
2-3-50-2, all but first and second. . 
41 9 
14 3 
8 2 
18 7 
32 
51 
Lime and tobacco dust, all applica- 
51 
Lead arsenate, 2-50, all applications.. 
52 
Total 
60 
196 
509 
263 
108 1 46 
2,836 
1,182 
It will be noted that the reduction of wilt was greater with the 
2-3-50 Bordeaux mixture than with the 1-2-50 mixture, although 
the number and weight of fruit picked was slightly greater for the 
weaker mixture. The wilt records show the effect of the treatments 
on the wilt alone, while a comparison of the number and weight of 
fruit for the various plats shows the combined control against both 
wilt and downy mildew (caused by Pseudoperonospora cubensis). 
The latter disease became prevalent during the month of xVugust 
(fig. 3). For control of wilt the last five treatments had no appre- 
ciable effect. Of the remaining four applications the two most 
