
15 
refuse of the plants must burned. On no account must + Ghie be 
dug into the ground ; this is simply sowing the seed for a new crop of 
p 
a which will be waiting for the next lot of onions planted on the 
“Te whenever the disease makes its appearance, the affected parts -of 
the onion are burned, there is some hope that in course of time the 
disease may be stamped out of the Lauda But this is only likely to 
be the case if the destruction of ther pos at universally practised. It 
oes not. And it must an ways be borane in anid that a small patch 
of diseased seme only a few square yards in area, will produce 
enough spores to ching every onion plantation in the Islands. 
It has been shown that the onion disease is perpetuated from one 
“ies : 
crop p: onions nee to appear. Ses northern clim age it is probable 
ere have been no direct da patil to determine how long the 
rag of the onion fungus retain their power of germination, 
but probably not for more than two or thre rs. Hence, if a piece 
to plant it with a different crop for a year o or two. This would afford 
ut. 
rotation of crops, pan with potatoes, is universally 
practised by the onion farmers of the Canary Islands, and is the 
common practice in Europe, Hoia so much because of the disease, but as 
a means of pho: the exhaustion of the soil. Hence, apart from 
the chance of diminishing the amount ai the dis pidii, jt would be 
advantageous to adopt this method of cultu 
cases where it is impossible to rotate the crops, and where onions 
must be planted in ground which was infected last A bea deep trenching i 
y recommended, this means the resting-spores would be 
buried at such a depth that they would fail to reach the surface and 
come in contact with the new onion c 
B 
& 
© 
Planting early in the autumn has to found to answer well in 
England as a means of avoiding the disease. When this is done the 
for the fungus to make its appearance. Owing to the difference in 
climate between on haga and Bermuda, it is hardly safe to predict that 
the same result would follow in the latter place, but the experiment 
might be tried. 
f there is any reason to suspect that the farmyard manure is a 
means of infection, through some refuse of a diseased onion crop being 
mixed foe it, or from any other cause, it would be advisable to water 
th ure with a weak solution of iron sulphate E280») aa 
putting i it on the land. One-tenth of a gramme in 100 grammes of 
Rotation of 
ps. 
Deep trench- 
ing. 
Early sowing. 
