336 REPORT OF THE COMMISSIONER OF AGRICULTURE, 
plants to be attacked by blight after the fruit is gathered. The 
death of the plants before the close of the season sometimes results 
from these late attacks. 
Some varieties appear to be more subject to the disease than others, 
but we are unable, at this time, to make any classification based on 
their degree of susceptibility. The following varieties have been 
mentioned* as among those most subject to the disease: Downing, 
Wilson, Russel’s Prolific, Big Bob, Bidwell, Captain Jack, Forest 
Rose, and Manchester; those notably free are Crescent, Windsor 
Chief, and Sharpless. 
(d) CONDITIONS FAVORING THE DEVELOPMENT OF STRAWEERRY-LEAF BLIGHT. 
Heat and moisture favor the development of Strawberry Blight, 
and at any time during the summer when the weather is hot and 
moist the plants are likely to be attacked. Heavy dews or rains are 
essential to infection, but the disease may continue its work of de- 
struction during dry weather; and it not infrequently happens that 
it develops in its worst form in dry, hot weather succeeding a period 
of frequent or heavy rains. The fungus causing the malady is truly 
parasitic in its habits, and, except that the conditions which may 
favor its development be inimical to the plants, the health or vitality 
of the latter does not enter into consideration. Other things being 
equal, plants, however vigorous and well cared for, are no less subject 
to the blight than those in feeble health. 
In respect to the soil, the disease is undoubtedly most severe when 
the land is heavy or wet and undrained. We have in mind an in- 
stance which will illustrate this point. <A plantation of about 5 acres. 
was bordered on one side by a brook, towards which the land grad- 
ually sloped. For about 60 feet back from the brook the soil was 
marshy and wet, while the remainder of the field was fairly well- 
drained. The plants on the narrow strip of wet land were much 
more severely diseased with bight than those on the comparatively 
dry soil adjoining. The effect was like that sometimes observed 
when two varieties—the one resistant and the other susceptible to the 
disease—grow side by side. In the present instance there were a 
number of varieties planted in rows running at right angles to the 
brook, so that the greater severity of the disease on the wet land 
could not be attributed to any difference in susceptibility of varieties. 
The disease in the locality here noted appeared early in May, some _ 
ten days after a heavy rain-fall which was succeeded by damp, cloudy 
weather. 
A deep and thoroughly well drained soil will supply sufficient 
moisture to keep the strawberry plants in good condition, but not 
enough to favor excessive development of the blight. 
(e) BOTANICAL CHARACTERS. 
The fungus causing the Starwberry-leaf Blight, although of micro- 
scopic size, is a plant like the strawberry itself, and consists of a vege- 
tative and a reproductive system; the former is the mycelium or plant 
body of the parasite; the latter comprises the spores or reproductive 
bodies and the organs supporting or containing them. 
The myceliwm.—The vegetative part of the fungus is made up of 
slender, thread-like tubes which grow between and sometimes into 
he cells of the host. These threads are colorless (sometimes tinted 
* Trelease in Second Ann. Rept. Wisc. Agr. Exp. Station, p. 48, 
