Nov. 20, 1916 
Laspeyresia molesta 
375 
DISTRIBUTION OF THE SPECIES 
So far as known to the writers, the insect in the United States is still 
confined to the general region of the District of Columbia. It is very 
generally present on peach trees in yards and elsewhere in the city of 
Washington and adjacent towns in Virginia and Maryland within a 
radius of 15 or 18 miles. Examples of injury to the peach by what is 
believed to be this -insect have, however, been seen in the environs of 
Baltimore. The insect is thought to have been present in the District 
of Columbia for four or five years, or perhaps somewhat longer. Speci¬ 
mens of injured twigs were received at the Bureau of Entomology in the 
fall of 1913, and the work attributed to an unknown lepidopterous larva, 
although they are now believed to have been injured by Laspeyresia 
molesta . A few examples of injured twigs were received or collected during 
1914 and 1915, but it was not until the fall of 1915 that its injuries were 
at all common. The writers were, unfortunately, not successful in obtaining 
adults from the larvae until the spring of 1916, and the single specimen 
then obtained did not prove sufficient for identification purposes. During 
the summer of 1916, however, an abundance of adults were reared and cer¬ 
tain observations made concerning the biology and injuries of the insect. 
CHARACTER OF INJURY AND HABITS 
The larvae have been found injuring twigs of the peach (Amygdalus 
persica ), plum (Prunus spp.), and cherry (Prunus spp.) and the fruit of the 
peach. The scarcity of the plum and cherry during 1916 in the infested 
area prevented observations as to the extent to which these fruits are 
attacked. The plum and cherry, however, have not shown such general 
infestation as observed for the peach, and it would appear that this 
latter is the insect's preferred food plant. It should be stated, however, 
that flowering cherries growing here and there in parks in Washington, 
especially the extensive plantings of Japanese flowering cherries in 
Potomac Park, are very generally infested. The twig injury to the 
cherry and plum is essentially the same as for the peach, though it is less 
conspicuous, due to less gum exudation (PI. 26, A, B). 
m 
TWIG INJURY 
In one peach orchard under observation an examination in mid-Sep¬ 
tember showed that from 80 to 90 per cent of the twigs had been injured, 
and an even higher percentage of twigs of adjacent peach nursery stock 
had been attacked. Its injuries to the twigs of bearing orchards, while 
important as interfering with normal growth, are of less significance than 
the injuries of the caterpillars to the fruit. Twig injury in nurseries, 
however, is of much more importance, as the destruction of the terminal 
growing shoots results in the pushing out of shoots from lateral buds, 
producing a much-branched and bushy plant unsuitable for nursery 
stock (PI. 27). Twig injury to newly planted orchards and to replants 
