THE G00SE13EERY MILDEW 
141 
of the Gooseberry in the United States. It not only attacks the fruit, 
but often extends over the whole plant, effectually checking its growth. 
So prevalent has this become that the foreign varieties are almost 
universally discarded, as there are few localities where they will succeed." 
The following account is given of the manner in which the fungus 
commences its attacks : — " The mildew first makes its appearance upon 
the young half-grown leaves and the unfolding terminal bud of the shoot. 
In its early stage it has a cobwebby appearance, which soon becomes 
white and powdery from the development of the light conidial spores. 
Soon after this thin patches of the same character may be found upon the 
forming berries. Usually one side is more attacked than the other, and 
as the berry continues to grow it becomes one-sided or curved, because 
the fungus retards the development upon the infested side. If the berry 
is entirely covered its further development is generally checked. Later in 
the season the leaves, and especially the petioles and the young stems 
bearing them, turn a rusty-brown colour, and become thickly coated with 
the fungus. The berries at the same time are covered with brown 
patches of mycelium, which may be readily peeled off from the smooth 
skin of the fruit." 
Goff (2), in 1888, tried the effect of potassium sulphide as a fungicide 
for diseased bushes, and found that the new^ growth, as well as the crop 
of fruit, was very perceptibly greater on the treated plants. The sub- 
stance was applied in solution in the proportion of one-half and one- 
fourth of an ounce of the potassium sulphide (" liver of sulphur ") to a 
gallon of water, and the spraying was commenced as soon as the 
leaves had begun to expand. The application was repeated after every 
hard rain. 
Close (3) has a valuable article on the present mildew, in which are 
detailed the results of experiments in treating the disease on a commercial 
scale. The attacks of the fungus are fully described as follows :— " The 
Gooseberry Mildew generally makes its appearance during the last half of 
May or first half of June. It is first noticed as glistening frost-like spots 
on the fruit on the lower part of the bush where there is usually dense 
shade. As the disease progresses the spots enlarge, turn dark brown, 
and form a felt-like covering over a part or all of the berry. . . . Two or 
three weeks after the mildew attacks the fruit it appears on the young 
tender twigs, especially on the tips. If the attack is severe the new 
growth will be destroyed, and the older growth will be considerably 
injured. In the case of a very severe attack the fruit will be rendered 
worthless, and the foliage will be nearly or entirely killed during July. 
As a result no fruit-buds are set for the next year's crop, and the bushes 
are so badly weakened that they may suffer from winter injury. In a few 
commercial plantations, where little or no spraying was done, the crop of 
fruit was destroyed and the bushes practically ruined by this disease. In 
other plantations, where spraying was carefully done, the greater part of 
the crop was saved, the foliage remained in good condition, and fruit-buds 
were set for a succeeding crop." 
A series of experiments was made during three seasons to test the 
comparative value of potassium sulphide, Bordeaux mixture, lysol, and 
formalin as a fungicide, and it was proved conclusively that potassium 
