74 



THE GARDENER'S MONTHL Y 



[March, 



detached, but when the conservatory is attached 

 to the dwelling, either of the two former will 

 answer. 



The next best known enemy to plants under 

 glass is the Red Spider, always found in greatest 

 abundance in a hot and dry atmosphere. When 

 a good force of water is obtainable, so that 

 plants can be syringed by hose, there is little 

 excuse for this insect, for it cannot exist to do 

 much injury where leaves can be forcibly wash- 

 ed by water. When there is not sufficient head 

 of water to syringe by hose, the next best thing 

 is some form of garden engine or hand-syringe, 

 in addition to which the paths and under the 

 branches should be copiously watered so as to 

 counteract the aridity of the air consequent from 

 lire heat. The fumes of sulphur is also destruc- 

 tive to red spider, but this can only be safely 

 applied by painting the hot water sides with sul- 

 phur, or if the greenhouse is heated by flue, it 

 is only safe to do so at the cold end, for if sul- 

 phur is volatilized in a temperature much higher 

 than 200° it will injure the leaves. 



The next insect in importance as injurious to 

 plants under glass is the mealy bug, a pest which 

 has made rapid increase in nearly all greenhouse 

 establishments, of late years, owing to the im- 

 mense increase in the growing of plants in high 

 temperature for the forcing of flowers in winter. 

 The usual method has been the tedious one of 

 rubbing the insects oflf with a soft brush ; and 

 until recently the scores of substances with which 

 we have tried to destroy the insect either failed to 

 do so, or else in ruining the insect they destroyed 

 the plant. I say until recently, for there is now 

 a certain remedy known as "Cole's insect ex- 

 terminator." This put on with a Barber's atom- 

 izer at once kills the mealy bug, without 

 injuring the most delicate or tender plant. The 

 serious objection to the " exterminator" is its 

 price, which is upwards of S2.00 per quart. A 

 quart, however, is sufficient to go over at least 

 1000 square feet of plant surface, as it is thrown 

 out by the atomizer in spray fine as mist. 



The Black Rust on verbenas, heliotropes, 

 petunias, etc, is caused by an insect known as 

 the verbena mite, too small to be visible 

 without a microscope. This, like nearly all 

 other parasites that attack plants, is rather a 

 consequence than a cause of disease, for we find 

 whenever plants are neglected, by being pot- 

 bound, or by insufficiency of water, or any other 

 cause that lessens the vigor of the plant, it is 

 more likely to be attacked. It is thought that 



the fumes of sulphur, given out by painting the 

 sides, is destructive to it, but of this we are not 

 certainly assured. There is but little doubt that 

 this insect spreads quickly, and it is safest when 

 plants are affected to at once throw them out, 

 for if seriously a8"ected they rarely recover. 



Ants are often troublesome in greenhouses. 

 A simple remedy is to steep pieces of bread or 

 sponge in some solution of sugar. They will 

 leave everything else for that, and soon thou- 

 sands of them may be thus caught and destroyed. 



Snails are often destructive, as they usually 

 keep under the benches during the day and come 

 up to feed on the leaves at night. I have 

 found that salt strewed along the edge of the 

 table was a complete barrier to their getting at 

 the plants from below. 



The Thrip is a troublesome insect, appear- 

 ing in quite a number of varieties on different 

 plants. The same directions may be given for 

 its destruction as for that of the red spider, 

 though in such plants as cannot be reached by 

 the syringe there is nothing for it but sponging 

 the leaves, or else in using the "exterminator" 

 with the atomizer, as is done with mealy bug. 



The Carnation Twetter, — so-called for want 

 of a better name, — is an insect but little known, 

 as its ravages are often ascribed to red spider 

 or thrip, but it has no resemblance to either. 

 Its presence is indicated on carnations or pinks 

 (we have never seen it but on plants of this 

 family), by the end of the shoot having a slight 

 curve or twist. If this twist is carefully unfold- 

 ed, the insect will be seen varying in length from 

 the sixteenth to thirty-second part of an inch, 

 and as thin as the point of a fine needle. It is 

 either green, yellow, or black, according to its 

 stage of development. In many places it has 

 completely destroyed, year after year, the whole 

 crops of carnations. It is believed to be fostered 

 by growing the plants in too high a temperature, 

 as we find it makes but little headway under 50°. 

 I can give no remedy except the general one, 

 to stimulate by manure water, or by any other 

 means plants so affected into a vigorous growth, 

 so, as it were to outgrow its ravages. 



I now come to the Rose Bug, the insect that 

 of all others is of interest at the present time, 

 owing to the vast quantities of roses grown un- 

 der glass, but as the subject has been recently 

 so thoroughly discussed, I can say but little new 

 in the matter. The rose bug, so-called, is in the 

 perfect insect about the size of a large house fly, 

 of a leaden-grey color, resembling in appearance 



