THE NATIONAL NURSERYMAN 
io8 
features suggests that the moths from hawthorn and cherry 
and those from apple constitute a single species; but cross¬ 
breeding experiments are desirable to settle definitely the 
status of the two forms. 
An outbreak of these insects is to be expected from two 
sources: (i) From the annual importation of infested 
foreign-grown nursery stock, and (2) from spread of the 
pests that may have established themselves along the 
avenues of trade in previous shipments. The remedy is 
careful inspection of nurseries during June and the destruc¬ 
tion of infested plants. As fruit pests, the insects would 
prove amenable to prevailing spraying practices. 
ARTIFICIAL MANURES AND PROPAGATION 
The use of artificial manure is now so general that it 
would be easier to find gardens where but little else in the 
way of manure is used than one wholly free of it. That 
there is much to be said in favor of artificial manure can¬ 
not be gainsaid, but at the same time the wholesale use of 
it has many drawbacks. In competition, nowadays, produce 
has to be grown to a pitch of excellence hardly attainable 
by what might be termed natural methods. Take for a 
moment Chrysanthemums; these can be fed with natural 
manures up to a certain point, but then, if the flowers are 
to excel, a more concentrated stimulant must be relied 
upon in order to give the last finishing touches, and rush 
the plants, if such a term may be used. 
Not long ago I saw a statement to the effect that it was 
unwise to “poison” Sweet Peas with doses of artificially com¬ 
pounded manures. This set me thinking. After due 
reflection and observance of the action of such manures, 
I must say that I have come to the conclusion that artificial 
manures do, to a very great extent, poison a plant. Of 
course, this process varies in intensity much as alcohol does 
to a man who drinks intoxicants, and just as a man who 
partakes of a moderate quantity of alcoholic liquor works 
off the effects, so to speak, and possibly benefits by the 
stimulant, so a plant which receives but little artificial 
exhausts the baneful after-effects, and by becoming hungry 
again does not accumulate poison. On the other hand, 
if a man drinks to excess we know what happens. He may, 
up to a given stage, wax fat, like the old time inn-keeper, 
but beyond that, if he once collapses, it is most difficult to 
“feed him up.” So, exactly, does this apply to vegetation, 
if fed artificially. The whole tendency is towards a gross 
growth, and the whole plant is working at forced speed, 
which, although very encouraging while it lasts, is neverthe¬ 
less liable to suddenly stop, and no possible means can then 
be devised to start the plant again with anything like its 
natural vigor. It is, in fact, poisoned. 
Now, what is the result of artificial manure on the next 
generation? I do not think it is an exaggeration to say 
disastrous. In many instances that have come under my 
notice during the last few years of several species of flowers 
which are popular as exhibition subjects, I have been struck 
with the difference in the cuttings taken from naturally 
grown plants or stools and those from artificially fed but 
otherwise similar stock. This fact is not so remarkable 
perhaps in the case of Chrysanthemums and similar flowers, 
where to a certain extent the cuttings are produced from the 
lower portion of the original stem, and from roots still remain¬ 
ing in the same soil as was frequently saturated with the 
manures. It is when we come to tubers, as in Dahlias, that 
the far-reaching effects of stimulants given during the pre¬ 
ceding autumn is plainly traceable. Very often roots or 
tubers grown in this way are extremely large, yet in spite of 
the apparent force thus stored up in the way of nourishment, 
the eyes start weakly, and the cuttings are both delicate and 
of bad color. Why this should be so I am quite at a loss 
to say, but from repeated experiments on roots of the same 
variety, I can definitely say it is so, and there is no question 
that, in the way of a tuber, which is grown absolutely on 
natural manures will produce better cuttings than the 
larger but artificially fed one. Also the cuttings of the first 
named will root much quicker than the other. 
This brings us to another most important point, and that 
is, what is the ultimate result of the artificial feeding? For 
instance, many growers maintain that cuttings taken from 
stools that have produced fine flowers are possibly weaker 
in constitution, but their strength runs more into bloom 
than foliage, and in the end a better flower is obtained than 
would be the case if the cutting had been stronger, but taken 
from a naturally grown parent plant. If this is so, the 
artificial manure may not be so hurtful as at first appears,, 
but I cannot fall in with this view, although it would at times 
look almost as if there is some truth in it. As, for instance, 
when a new Chrysanthemum is introduced, and it becomes 
more floriferous year by year, as if gradually the stock be¬ 
came more capable of producing flowers; but this, I think, 
is to be accounted for by the growers becoming more and 
more used to the habit and peculiarity of any given variety. 
—Harry Stredwick, Journal of Horticulture. 
PHYSIOLOGICAL EFFECT OF BORDEAUX 
MIXTURE 
During the past five or six years experiments were carried 
out in Germany with a view to determine whether the in¬ 
creased yield resulting from spraying with Bordeaux mixture 
was due to a physiological effect on plants. In some experi¬ 
ments with potatoes, radishes, and beans, the crop decreased 
with an increased strength of Bordeaux mixture used. 
The mixture was found to have a favorable physiological 
effect only in dry weather, the mixture acting by hindering 
transpiration from the leaves. It was considered possible 
that the coating of copper sulphate also acted as a shade 
to the plant from an excessive amount of sunlight in hot, 
sunny weather, and thus prevented an early ripening of the 
haulm. The repeated spraying of currants and gooseberries 
with Bordeaux mixture had the effect of increasing the 
sugar content of the sap of these fruits. This was shown 
not to be due to the fungicidal action, as spraying immune 
varieties of fruit had the same effect; nor to any increased 
assimilative activity of the leaves, the latter, indeed, decreas¬ 
ing as a result of the spraying .—The Gardeners' Magazine. 
