July i, 1925 Overwintering and Dissemination of Cucurbit Mosaic 
19 
Table VIII .—Occurrence of mosaic on Micrampelis lobata in various localities 
as related to the presence of the disease on cucumbers in the vicinity 
Date 
Locality 
Square 
miles of 
area 
covered 
Number 
of cen¬ 
ters of 
Micram¬ 
pelis 
Number 
of 
mosaic 
centers 
Occur¬ 
rence of 
mosaic 
on cu¬ 
cumbers 
in area 
Survey of 1919 
July 9__.. 
Sturgeon Bay, Wis__ 
1.5 
7 
o 
o 
July 10__ 
Ellison Bay, Wis... 
1. o 
2 
o 
o 
Do_.. 
Green Bay', Wis____ 
2. 5 
11 
o 
o 
July 25... 
1.0 
6 
o 
o 
July 24.. 
Menominee, Mich. ... . 
2 0 
13 
o 
o 
Do__ 
Marinette, Wis_.__ __ 
1.5 
11 
o 
o 
July 11... 
Racine, Wis___ 
4. 0 
19 
4 
(a) 
July 18__ 
Madison, Wis__ 
5.0 
24 
10 
(b) 
July 22.. 
Milwaukee, Wis_ __ 
1.5 
6 
o 
(a) 
Aug. 30.. 
_do_I___ 
2.0 
g 
2 
(a) 
July 26_ 
Portage, Wis..... 
3.0 
g 
3 
hi 
Aug. 28_ 
Ripon, Wis____ . 
2.0 
27 
11 
hi 
Aug. 29... 
Princeton, Wis.... 
2.0 
30 
19 
Do___ 
Fond du Lac, Wis. _ _ . . . . 
0.5 
5 
1 
(•) 
Survey of 1920 
June 11_.. _ 
Sparta, Wis____ 
1.0 
g 
5 
( b ) 
July 24__ 
Harvard, HI___ 
2.0 
18 
g 
(b) 
July 26... 
Marengo, Ill___ 
1. 5 
11 
5 
(a) 
Aug. 24... 
Huntington, Long Island__ 
(c) 
1 
1 
(°) 
Aug. 25_•_ 
Riverhead, Long Island___ 
2.0 
3 
1 
(«) 
Aug. 26.. 
Southampton, Long Island. ... 
( c ) 
1 
1 
(•) 
• Indicates presence of mosaic. b Unusually severe mosaic infection. • No definite area covered. 
As shown in Table VIII, no mosaic was found on cucumbers in 
the district around and north of Green Bay, in northwestern Wis¬ 
consin. There is no record of the disease in this section, although 
cucumbers are grown on a commercial scale in most of the localities 
visited. No mosaic was found on any wild cucumber plants in this 
part of the State. On the other hand, a survey over much of the 
cucumber-growing territory in the southern portion of Wisconsin 
revealed the more or less frequent occurrence of mosaic on the wild 
cucumber correlated with its presence on the cultivated cucurbits 
in the vicinity. 
In many localities the disease was found on a considerable num¬ 
ber of Micrampelis plants, while in other places it occurred on but 
few. As closely as could be estimated from observations of this 
type, there was a very striking correlation between the number of 
groups of mosaic plants of the wild cucumber and the extent of the 
disease in the fields, although, as previously stated, it was impossible 
to draw conclusions too definitely from observations made in various 
localities over a period of only six to seven weeks. It will be seen 
from Table VIII, however, that the disease was found on a number 
of wild cucumber plants at Madison, Ripon, and Princeton, Wis., 
during 1919, and that the disease was unusually severe in the fields 
at these points. Ripon and Princeton are of particular interest from 
the fact that the disease is known to have occurred in these localities 
as early as 1900, the earliest record of its appearance in Wisconsin. 
It has always been particularly severe in both places. The survey 
LiBRARl 
CEREAL INVESTIGATIONS’ 
