?ol. LXII. No. 2777. 
NEW YORK, APRIL 18, 1903. 
II PER YEAR. 
A BETTER FUNGICIDE THAN BORDEAUX. 
EXPLANATIONS BY A SCIENTIST. 
How to Improve the Mixture, 
ACTION OP COPPER.—In The R. N.-Y. of Janu¬ 
ary 17 three wants were expressed as follows: An 
improvement in Bordeaux Mixture; a better insecti¬ 
cide for the Potato beetle, and a remedy for Melon 
blight. The scientist as well as the grower has been 
anxious to find some mixture that will give the pro¬ 
tection desired with less labor of preparation and 
application than is required with the Bordeaux Mix¬ 
ture. It was found that solutions of copper salts were 
more effective fungicides than any other easily- 
obtained chemicals, and of the copper salts, copper 
sulphate was equal in activity and cheaper in price 
when compared to other copper compounds. Thus we 
are limited from the side of expense and from the 
side of efficiency to copper compounds. The fruit 
grower know's that poorly-made Bordeaux Is likely 
to injure his foliage; the scientist has recognized the 
same fact and by careful experimentation has found 
that the injurious effect is 
due to exactly the same 
action as the beneficial ef¬ 
fect of Bordeaux Mixture. 
A living plant cell has the 
power of absorbing from 
solutions the chemical 
compounds which they 
may contain, whether 
these compounds are help¬ 
ful or injurious to the 
health of the plant cell it¬ 
self. This absorbing pow¬ 
er varies with the plant 
and with the chemical 
concerned. It has been 
found oy careful test that 
the copper salts are easily 
soluble in the plant juices, 
and when so absorbed are 
fatal to the life of the 
plant cell if in consider¬ 
able amount. The pro¬ 
perty of absorbing chemi¬ 
cal solutions, whether in¬ 
jurious or otherwise, is 
the means whereby the 
fruit grower protects his 
trees when he sprays them 
with Bordeaux Mixture. It is a “fruit insurance.” 
The copper compounds contained in the Bordeaux Mix¬ 
ture are dissolved by the activity of the germinating 
fungus spore just as they would be by the cells of a 
germinating seed, and they kill the spore as it germi¬ 
nates just as they would kill the cells of the germi¬ 
nating seed or plant cells, absorbing the solution. 
WHY LIME IS ADDED.—Lime is added to the Bor¬ 
deaux Mixture in order to check the rapidity with 
which the copper solution may be absorbed by the 
plant on which it is sprayed. The fungus spores, 
however, as they germinate, absorb sufficient copper 
sulphate from the Bordeaux Mixture upon the leaf to 
Pause their own death. The lime checks the solubil¬ 
ity of the copper sulphate and hence decreases the 
amount absorbed in any given period by the cells of 
the leaves to which it is applied. In the case of 
peaches the cells of the leaves are not protected by 
any considerable protective coating, such as exists 
in most other leaves except Japan plum, and as a 
consequence, the copper sulphate is readily absorbed 
if applied in the ordinary Bordeaux strength. Hence 
for peach and plum we use a more diluted prepara¬ 
tion, in which the proportion of lime is much in¬ 
creased, making the solubility of the copper less but 
leaving It still available for the killing of the fungus 
spores as already described. So much for the action 
of Bordeaux. Now for a better Bordeaux. 
IMPROVING BORDEAUX.—As stated, copper solu¬ 
tions are the most deadly of those easily obtained by 
the farmer when applied against fungus diseases. So 
far as the effect is concerned, Bordeaux Mixture is as 
good as we need. So far as convenience of applying 
is concerned, there is opportunity for considerable im¬ 
provement. A large portion of this improvement 
should come through the increased skill on the part 
of the growers, enabling them to economize in time 
and labor and in material. Another point which the 
fruit grower may help himself is in the application 
iti'elf. It has been shown by careful experiments that 
a fine mist-like spray is more effectual as a fungicide, 
that it protects the foliage better, and that it remains 
longer on the surfaces than when applied in large 
drops and wetting the surfaces to the dripping point. 
It is a matter of common observation that a person’s 
clothing will retain more water uiion the .surface when 
exposed to fog than it will when exposed to rain. 
This, of course, does not apply to the amount of water 
passing through or running off from the garments in 
question, but simply considering the amount remain¬ 
ing on the surface of the clothing. After one has been 
exposed to fog, it would be difficult to place a pin head 
on his clorhing where it would not find a globule of 
the fog to wet it. The same thing is true in regard to 
spraying. It is that part of the Bordeaux which stays 
on the plant which is beneficial, not that part that 
runs off or that gathers along the margins of the leaves 
and there becomes injurious. The injury in the latter 
case is due in a large measure to the evaporation of 
the v/ater from the spray solution and the consequent 
concentration of the mixture adhering to the leaves. 
Bordeaux is recommended of a certain strength, as 
that strength has been found under normal conditions 
to be effective and safe, but when the ordinary coin- 
ditions are lost through the concentration of the mix¬ 
ture on the leaf, the normal proportions are no longer 
maintained and injury results. This injury, as has 
been already stated, is very much less likely to occur, 
for it is practically absent, when the spray is applied 
in the form or a mist. 
A STOCK SOLUTION.—Labor of preparation of 
Bordeaux Mixture can be materially decreased by the 
use of stock solutions, in which each gallon of solu¬ 
tion contains one pound of sulphate or of lime. Hence 
instead of weighing out the amount to be used each 
time a barrel is fiiied with the spray mixture, enough 
sulphate is dissolved and enough lime slaked to a 
creamy consistency at one time to last for several 
applications. By taking from this stock solution as 
many gallons as the formula may call for, the sprayer 
secures as many pounds of the mixture as he takes 
gallons of the solution, and does not have any weigh¬ 
ing to do. Unsatisfactory results are often caused by 
the improper mixing of the Bordeaux. The two com¬ 
ponents, sulidiate and lime, should be diluted to at 
least one-fourth of the final amount and then poured 
both nt omv into the spray tank. When diluted to one- 
fourth each, the remaining amount of water should 
be added immediately, and stirring should be carried 
on at all times while in preparation. Here in Mary¬ 
land it is the custom to dilute each solution to one- 
half the final amount and then mix by pouring at one 
time into the spray tank, which is meanwhile stirred. 
Bordeaux prepared as above has been found here to 
be thoroughly satisfactory 
and effective, and not to be 
seriously difficult or incon¬ 
venient in preparation. 
SPRAYING A NECES¬ 
SITY.—There are opera¬ 
tions on or about the farm 
that are just as hard and 
just as dirty as the prepar¬ 
ation and application of 
Bordeaux Mixture, but 
through generations of 
custom the farmer regards 
them as part of the sea¬ 
son’s work, and hardly 
gives the dirt or incon¬ 
venience a thought. Spray¬ 
ing is something new, and 
from this point its difficul¬ 
ties are magnified beyond 
their proper relationship 
and used as arguments 
against the use of the 
“f r u i t insurance.” The 
fruit grower will soon 
think as little of applying 
Bordeaux or lime, sulphur 
and salt as he now thinks 
of the application of barn¬ 
yard manure or other regular occupations which may 
be thoroughly disagreeable and bothersome, if he 
should stop to think of that side. The object then, 
cannot be gained by a substitution of some other 
remedy for Bordeaux Mixture with our present knowl¬ 
edge of the action of chemicals upon plant life, but is 
rather to be found in a better adaptation on the part 
of the fruit grower to the necessities in the case, so 
that he will find in spraying only another of the regu¬ 
lar duties of the year, and will with practice find 
him.self able to apply the remedies without trouble. 
Maryland Exp. Station. v. ii. blodoett. 
R. N.-Y.—Too much emphasis cannot be put upon 
the need of a very fine spray, just as near fog as pos¬ 
sible. When spraying liquids containing substances 
likely to cause clogging there is a temptation to use a 
nozzle so open that there will be no trouble of this 
sort, but this is only an apology for spraying, and 
never gives satisfactory results. Like a heavy rain, 
most of the liquid reaches the ground, and the force 
with which it strikes the leaves knocks off much that 
would otherwise remain. It is better to have an oc¬ 
casional tussle with a clogging nozzle that puts the 
misty spray where it should be, than to use one that 
wastes the liquid, but does a quick job. 
< i J f / ,• / : 
Mil. Fak-mkk: ‘-Ah! Here is a signboard. Perhaps that 
will tell me how to get thei-e.” 
He strikes a m.iurh and ilnds out. 
A MATCH REVEALS ’THE ROAD TO GET THERE 1 Fig. 105. 
