PLANT LICE OK APHIDS. 



here given ; it is an entrance to a garden 

 in Russia, more elaborate than would be 

 attempted by many of our Canadian 

 gentlemen, but giving some suggestions 



well worthy of consideration. The pic- 

 ture is from the American Florist, and 

 belongs to a garden at Norgorod, which 

 is one of the finest in that city. 



PLANT LICE OR APHIDS. 



T is becoming more apparent every 

 year that to be successful, the 

 ,_1 horticulturist must be familiar 

 with the essential principles and 

 facts of economic entomology. Every 

 season has its especially bad insect pest, 

 and, generally speaking, so little is 

 known of the life histories and character- 

 istics of even our common forms that 

 they are often neglected till too late, or 

 are fought with inadequate and ineffec- 

 tual weapons. No better illustration 

 could be given than the case of plant 

 lice. We have had a scourge of these 

 most injurious insects this year. I do 

 not recall so bad a visitation for six 

 years, and the damage done by them 

 has been greater than that by any other 

 insect, yet, in a very limited experience, 

 I have heard of many cases, where 

 afflicted gardeners and fruit growers 

 have dosed the enemy with Paris green, 

 and have been very much astonished 

 and disgusted to find that it " didn't 

 fizz on them." A very little insect lore 

 would have saved them from such a 

 mistake. 



The question of why we get a big 

 plague of this and that insect, and then 

 are free from trouble for years is an 

 extremely interesting one, but would 

 take too long to enter into here. Clima- 

 tic conditions are largely responsible, 

 and the other main cause is the absence 

 or presence of nature's checks, the para- 

 sitic and predaceous forms of insect life. 

 A decrease in a predaceous species 

 means an increase in its prey. After a 



while the predaceous insects catch up, 

 the oscillation is continued ad iiifiniium, 

 and the balance of natural forces is thus 

 maintained. It is, of course, comforting 

 in a vague way to know that Nature is 

 on our side ; and to feel that next year 

 our special enemies of this year may be 

 wiped out. The comfort is very con- 

 siderably lessened by the fact that we 

 are "getting it in the neck " meanwhile. 

 We must forge our own weapons, but a 

 knowledge of the foe's vulnerable points 

 becomes indispensable, and so, revetwns 

 a nos moutoits. 



Plant lice are members of the family 

 Aphidaa, belonging to the section 

 Homoptera, and the order Hemiptera. 

 This section or sub-order Homoptera, 

 includes all the bark lice, leaf hoppers, 

 plant lice, mealy bugs, scale insects, 

 etc, and contains practically nothing 

 but injurious forms of insects, some of 

 them extremely difficult to fight. They 

 are characterised in common with all 

 the hemipterous insects, by the pos- 

 session of a suctorial mouth apparatus, 

 only taking their food in a liquid form, 

 whether it be animal or vegetable. 

 They are further marked by the general 

 insignificance of their size, and the 

 extraordinary rapidity with which they 

 breed, dangerous characteristics as far 

 as we ate concerned. Of the family 

 Coccidie in this order one would like to 

 speak, if time permitted. The Coccids 

 or scale insects are lice that form over 

 their bodies a protective, waxy scale of 

 various kinds. The most injurious of 



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