Msy 5,1887. ] 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
347 
5 
TH 
Linnean Society at 8 p.m. 
6 
F 
7 
S 
8 
SUN 
4th Sunday after Easter. 
9 
M 
10 
To 
Royal Horticultural Bociety. Fruit and Floral Committees at 11 A.M. 
11 
W 
THE PREVENTION AND DESTRUCTION 
OF INSECTS. 
ARDENERS and cultivators of plants, trees, 
and crops generally have many enemies to 
combat, and must ever be on the watch to 
prevent some of them stealing a march and 
taking a firm position from which they can- 
not be dislodged without injury, not to them- 
selves alone but to the possessions on which 
they' have seized. Insects in various forms 
start into life with the same regularity that leaves unfold 
in spring, and those insects fight for existence with a 
determination that often leaves them victors. 
The increase of insects leads to the ruin of plants and 
crops, disquietude of minds, and the emptying of purses. 
The waste is enormous, and if it were possible to estimate 
the amount of damage done, with the outlay incurred in 
the general warfare against the enemy, it would be startling 
in its immensity. Undoubtedly one of the most important 
duties of the gardener is to mitigate as far as it lies in 
his power to do so the great evil wrought through insect 
agency, and it is certainly in the interest of the owners 
of gardens to give all the assistance they can in futherance 
of that object. 
There is no greater mistake made in gardening, and 
unfortunately few more common, than to lightly ignore 
the presence of one or two insects. It is no more safe or 
prudent to do so than to pay small regard to the out¬ 
break of a fire in a warehouse of valuable combustibles. 
The first spark if seen may be stamped out easily, but 
hesitation is fatal. It is the «same in respect to insects. 
Let the first arrivals remain undisturbed, on the ground 
that such a few cannot do much harm, and it is “ not worth 
while wasting tobacco or other insecticides on them,” 
and injury if not ruin to the plants and crops Avill be 
inevitable. The greatest calamities have followed from 
underrating the strength of the enemy, and permitting the 
aggregation of units till they grow into a mighty force. 
This is precisely what is done and permitted yearly in 
greenhouses and gardens all over the land. The first few 
aphides are weak and easily subdued, but allow them a 
few days’ freedom and they will entrench themselves so 
firmly and increase with such rapidity as to become a 
formidable foe. 
To allow insects to multiply into a devastating swarm 
is both costly and cruel—costly because the deplorable 
results in the form of half-spoiled Vines, fruit trees, and 
plants represent a great waste of wealth; and because a 
far greater outlay must be incurred in insecticides and 
labour in applying them to prevent total ruin, that 
originally would have insured a profitable return in the 
realisation of healthy plants and profitable crops. It is 
No. 358 .—Vol. XIV., Third Series 
cruel to even passively encourage the increase of insects, 
and then, as must be the case, engage day by day in 
the miserable work of carnage—it cannot be otherwise 
designated. It is cruel to the plants and trees also, in 
having their life blood drained away by the enemy that 
has been suffered to infest them, and which might have 
been prevented if the requisite means were provided and 
promptly applied. The owners of gardens are responsible 
for providing the means, the managers for their application. 
Insects have often gained the mastery over gardeners 
through the mistaken policy of waiting till plants and 
trees are seriously infested before even “ ordering ” in¬ 
secticides for their extirpation. Such delay on the part 
of those owners of gardens who themselves order what is 
needed is a serious mistake; in the case of gardeners who 
can provide themselves with every requisite it is inexcus¬ 
able. A shilling spent in insecticides early in the season, 
and the powder or solution applied when the first insect 
is seen, or what is better before, as a preventive, will 
effect the desired purpose far better than can be accom¬ 
plished by an expenditure of 20s. after the shoots of trees 
and plants are crowded with aphides, which, further, by 
puncturing the leaves, cause them to curl over and effectu¬ 
ally protect the enemy that is depriving them of life. 
The rapidity with which plant lice multiply is mar¬ 
vellous, and perhaps not sufficiently recognised. Accord¬ 
ing to the calculations of Reaumur, five generations 
proceeding from one mother produced 5,904,900,000 in 
a season. It is true there are natural enemies for checking 
the increase, as ladybirds and ichneumon flies in nature, 
but they are rarely present, and never in sufficient numbers 
early in the year, where cultivation is practised to a 
large extent under artificial conditions. The natural 
enemies of insects must never be relied on for destroying 
the latter, but other agencies should be resorted to for 
preventing the appearance of the pests, or at least be 
applied with promptitude when the first insect is seen. 
Waiting till the young growths of trees and plants are 
much infested with insects before remedies are applied is 
placing the latter at a great disadvantage, ajid is often 
unjust to the manufacturers of insect-destroying com¬ 
pounds. Used in time, a moderate strength suffices for 
the extirpation of plant pests and leaves the plants un¬ 
harmed, but when insects cluster on each other in layers, 
and so affix themselves as to make their prey their shelter, 
much stronger and repeated applications are called for; and 
^is these cannot destroy the insects they do not reach, and the 
exhausted foliage cannot withstand the strong applications, 
what has been applied is not only pronounced useless but 
dangerous. Nothing can be more unfair. The fault is 
too near home to be admitted perhaps, but it is there 
nevertheless, and not with the insecticides, for if those 
that, have been found safe and effectual by experienced 
cultivators, and used in strict accordance with the makers’ 
instructions, and especially used in good time, before 
insects abound, they will answer the purpose for which 
they were intended. This latter condition is of far 
greater importance than the choice of any particular pre¬ 
paration. Some persons find one kind answer their pur¬ 
pose, some another, and it is a question if there is one in 
the market that is not safe and good when fairly applied. 
Greenhouse plants innumerable, Calceolarias, Cinera¬ 
rias, Pelagoniums, and others; also Roses in and out¬ 
doors; Peaches and other trees on Avails and under glass; 
Vines, Cucumbers, and Melons are crippled in growth, 
seriously injured, and not infrequently completely spoiled 
by aphides, thrips, or scale in their several forms that 
No. 2014.— Vol. LXXVL, Old Series. 
