INSECT PESTS AND WAYS TO 

 DESTROY THEM 



HOWEVER carefully and judiciously we may cultivate our gardens by 

 growing the plants most suitable for the soil, and placing them in the 

 most favourable situation for their growth, we still have to reckon 

 with a host of insect pests that are almost certain to infest them. 

 In spite of all our care, there is no doubt but that plants grown in 

 favourable circumstances and in robust health are less liable to the 

 attacks of insects and fungi than those which are unhealthy and not 

 in a vigorous condition, but still they are liable to be attacked. It is 

 impossible on the present occasion to describe all the various insects 

 that injure plants ; but that is not really necessary, as the great thing 

 from the gardener's point of view is to know how to destroy them, 

 and many may be dealt with by the same means. It is important to 

 realise that an insect may be found in four different states or condi- 

 tions, namely, as an egg, a grub or caterpillar, a chrysalis, and as a 

 perfect insect capable of propagating its species. It is true that some 

 insects are never grubs or caterpillars, or become chrysalides, for at simi- 

 lar periods of their life-history they more or less resemble their parents ; 

 still the change from one state to another is well marked, and the four 

 different conditions are assumed (of course, there is no rule without 

 an exception). It is important to bear this in mind, for sometimes, 

 though an insect is quite harmless in one state, it is very destructive 

 in another, and it may be that it is easier to destroy it in its harmless 

 condition than in the one in which it is injurious. Insects, as far as 

 their powers of injuring plants are concerned, may be roughly divided 

 into two classes : those that injure the plants underground, and those 

 that attack the parts of the plant which are above the surface of the 

 soil. The former are, on the whole, perhaps the most injurious, for 

 they attack a plant at a very vital part, namely, the root, and for 

 obvious reasons the first intimation of their presence is given by the 

 plant beginning to flag or droop, or show some signs of distress, so that 

 the plant has already sustained considerable injury before we know that 

 it is attacked ; then when we realise that a certain plant is infested at 

 its roots by some pest we cannot in most cases destroy it by means of 

 an insecticide, as a large quantity would have to be used, and of more 

 than ordinary strength (for the soil acts as a filter to a great extent), 

 which would be very hurtful to the plant already weakened by the 



injuries to its roots. So that, in the case of plants grown in the flower 



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