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of copper sulphate and lime, i. e. with a considerable excess of 
lime. So far as 1 have seen, if Bordeaux mixture is made (like 
that made, from the Woburn Bordeaux Paste) with practically no 
excess of lime,* it either does not adhere so well to the parts 
sprayed, or more quickly washes off under the action of rain or 
dew, and consequently does not protect the plant for long from 
fungus pests. In 1908 I compared the adhesive power of Bordeaux 
mixture made with “ milk-of-lime,” <?., a mixture containing an 
excess of lime, with that of the mixture made with “lime-water,” 
/, e., a mixture containing no excess of lime. The two mixtures 
were tested in potato spraying on a fairly large scale. It was 
found that the latter mixture was washed off comparatively soon 
by the rain, and in consequence of this the “ blight ” ( Phptophthora 
infest ans) was not kept in check to anything like the same extent 
as where the haulm had been sprayed with the Bordeaux mixture 
made with “ milk-of-lime.” Experiments were made during 1909 
with Bordeaux mixture made from the Woburn Bordeaux paste,- 
both on apple trees and on potato haulm. In both cases all 
visible traces of the spray had disappeared several weeks before 
the spray from Bordeaux mixture made with “ milk-of-lime '* had 
become washed off. In the case of apple fotiage, the “ scab ” 
fungus began to grow on the leaves, showing that there was a 
complete absence there of any fungicide. The same experience 
has been reported to me by a fruit-grower in East Kent, who for 
several seasons past has been successful in keeping a large acreage 
of appeals practically free from “ scab ” by spraying with home- 
made Bordeaux mixture, although previously this paste had been 
very prevalent. This grower writes as follows : “ I experimented 
with the Bordeaux paste and used it in exactly the same way as 
that which I made myself and found it practically worthless. 
Those trees which were sprayed with it (three times) were covered 
with apple “scab,” while those sprayed with the home-made 
mixture were kept practically free.” On the other hand, a fruit- 
grower in Sussex tells me that the use this season of Bordeaux 
mixture made from the Woburn paste kept his trees healthy, 
although last season they suffered severely from “scab.”* 
From my own experience I should advise the commercial 
fruit-grower at present — until more experiments have been made— to 
continue to make the bulk of his own Bordeaux mixture himself, 
while using a small quantity of the Woburn Bordeaux paste 
experimentally. 
II. The Application of Bordeaux Mixture - The best type of 
spraying machine for spraying with Bordeaux mixture depends to 
a large extent on such circumstances as the height of the trees 
" Bordeaux mixture containing no excess of lime can be easily made by using just 
enough lime, in the form of “ lime-water,” to precipitate all the copper (see Woburn Expcr. 
Fruit Farm. 8th Report, p. 9 (1908). 
Mr. Pickering (Woburn Expt. Fruit Farm, nth Report, p, (78) says, “Reports re- 
ceived have led to the conclusion that the paste has been about as efficient [during the 
season 1909I as ordinary Bordeaux mixture.” 
