100 
In the greenhouse this insect may breed thrnout the year, but 
as a rule it is not to be found during the winter months, when 
temperatures in the greenhouses are decidedly cooler than at other 
seasons. In the Chicago greenhouses I first found the leaf-tiers 
on the small plants in the latter part of April, but they do not be¬ 
gin to be noticeably injurious until some months later. 
This leaf-tier is found in all parts of the United States, and 
altho it feeds on outdoor plants to a slight extent, it is essentially 
a greenhouse pest. 
Among the more important greenhouse plants on which it has 
been bred, are Ageratum, Geranium, violet, dahlias, chrysanthe¬ 
mums, carnations, Cineraria , Begonia , rose, Pelargonium, and 
spearmint. The chrysanthemum and hothouse spearmint are, 
however, the only plants which I have found badly injured by it. 
In one greenhouse, containing several varieties of chrysanthemums, 
it seemed decidedly to prefer the Major Bonnaffon and the 
Rosiere, while the Timothy Eaton and the Yellow Eaton, which 
were growing between the benches of these, were but very slightly 
infested. 
Natural Enemies. —A hymenopterous parasite of this leaf-tier 
was common in the greenhouses in Chicago, and no doubt in many 
of them it was doing much to hold the leaf-tier in check. The. 
species was determined by Mr. Chas. T. Brues as Apanteles 
glomeratus Linn. A tachinid fly bred from this leaf-tier was 
determined by Mr. C. A. Hart, as Phorocera parva Bigot. 
Remedies. —To deal effectively with this insect, the grower 
must be on the watch for its first appearance, in April or May; 
or, if it has previously infested the house, it is better to commence 
spraying as soon as the chrysanthemums are well started. The 
larvae are then comparatively few, and the killing of one is equiva¬ 
lent to the destruction of dozens at a later time. Treatment of 
the plants is easier then than afterwards, and requires less time 
and material. Of the various poisons that may be used arsenate 
of lead is to be preferred, as it does not injure the chrysanthemum 
leaves, and remains on them much longer than Paris green sprays. 
The under side of the leaves must be thorolv sprayed, as it is 
there that the larva is usuallv to be found. Care should be taken 
to get a standard brand of arsenate of lead, such as Bowker’s 
“Disparene” or Swift’s or Grasselli’s arsenate. 
Light traps and hand-picking, recommended for the leaf-roller, 
(page 98) are equally effective against the leaf-tier. 
