Iv] Mildews 55 
be ascertained by squashing one under a coverslip. 
This fungus also causes considerable damage to straw- 
berries. This mildew also lives on several weeds, such 
as dandelions, meadow-sweet, and wild geraniums, but it 
has not yet been shown that hop plants can be infected 
from these weeds. 
Remedial Measures. 
Its position on the outside of the plant offers easy 
means of attacking this fungus. Sulphur in various 
forms has proved very useful. There are several 
fungicides used against this mildew: 
(1) Flowers of sulphur, 
(2) Liver of sulphur, 
(3) Lime and sulphur, 
(4) Bordeaux mixture. 
It is important to spray the plant early, i.e. as soon 
as or even before the mildew makes its appearance. 
Later spraying depends on the weather. All badly 
diseased plants should be burnt. 
American gooseberry mildew, Sphaerotheca mors- 
uvae, is a member of the same genus as the hop mildew. 
It is scheduled under the Destructive Insects and Pests 
Act, and all cases should be reported to the Board of 
Agriculture and Fisheries. 
Rose mildew (Sphaerotheca pannosa) which causes so 
much trouble to rose growers is a suitable form on which 
to try experiments. Watch some rose trees as soon as 
the leaves are out for the appearance of mildew and 
when it appears treat them in the following manner. 
Leave Set I untreated for comparison with Sets IT 
and III. Dust the trees of Set II with a coating of 
