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Until recently it -was thought that nicotine spray solutions and 
dusts passed into the spiraeles and caused death by suffocation. It is 
now known that spray solutions, without soap or other spreader, do not 
pass through the spiracles into the tracheae. If they contain a spreader, 
however, they do pass into the tracheae, although their presence inside 
the insects does not necessarily cause death. Only nicotine vapor from 
spray solutions, exhalations from nicotine dust, tobacco powder, or from 
dried films of spray solutions, and fumes from "burning tobacco pass far 
into the tracheao and are widely distributed to all the tissues, particularly 
to the nerve tissue, which is the first to be affected fatally. 
V. KINDS OF ANmALS AGAINST VfHICH NICOTINE YlkS EFFECTIVE 
According to the literature prior to 1934, nicotine was effective 
and had beer, recommended against only those organisms having soft bodies 
and others of minute sise, such as mites, thrips, aphids, psyllids, leaf- 
hoppers, crawling scale inseets, capsids, laeebugs, lice on poultry, 
midges, mushroom flies, sawflies, and grapevine moths. These and a few 
mare are discussed somewhat in detail in the following pages, being 
arranged by orders, families, a»d species. 
INSECTS, KITES, AKB TICKS CONTROLLED BY NICOTINE 
I . HW'OJTSEA 
Plant Lice, or Aphids (Aphiidae) 
TToolly apple aphid .--The application of nicotine has usually effected 
a satisfactory control of the woolly apple aphid ( Eriosoma lanigerum (Hausm. )) 
since 1814, but as this species is covered with a woolly or waxy covering a 
spreader is always required ir. the wash or spray solution. This aphid'becurs 
in two forms— the aerial form living on the limbs and leaves, and the root 
form on the roots. It appears to be universally distributed with the apple 
tree, for according to the literature it has been treated in 16 countries. 
In Europe up to the 1890* s the wash or spray mixture consisted of tobacco 
juice, water, and soap, and sometLmos sulfur or lime was added. After 1898 
concentrated tobacco juice, whose nicotine content was determined . 
by the hydrometer or by titration, was incorporated with water and soap, 
and it was common in Europe to add alcohol, sodium or potassium carbonate, 
or even oil. After 1910 it became common practice to use Black Leaf (3 per- 
cent nicotine) and Black Leaf 40 with soap or an oil omulsion in the following 
countries (chronological arrangement ) : United States, New Zealand, Tasmania, 
Australia, Korea, and Canada, 
Since 1884 tobacco has been used as a remedy for aphids on the roots. 
The method is to remove the earth around the base of the tree and over the 
roots, then to put an abundant supply of v/aste tobacco or tobacco dust 
against the wood bearing the aphids, and finally to cover the tobacco and 
roots with earth. The insects in time should be killed or driven away, but 
this method is often unsuccessful. 
