New York AGRICULTURAL EXPERIMENT STATION. 19 
DEPARTMENT OF ENTOMOLOGY. 
The willow borer as a nursery pest— The willow borer (Cryptor- 
hynchus lapathi L.) is an insect of growing importance to the 
-nursery interests of this State. Native willows along streams, 
swamps and canals are also frequently badly attacked, and in- 
juries are being sustained by certain species of willows planted for 
ornamental purposes. The species of plants observed to be con- 
spicuously injured are Populus monilifera, Salix lucida, S. caprea, S. 
cordata, S. sericea, S. alba and S. amygdaloides. 
. Investigations were commenced in 1905 to determine the habits 
of the insect and practical means of protecting nursery stock. The 
life history has now been completely studied. It was found that 
this species has one brood a year. Oviposition occurs in the corky 
‘portions of the wood, near a bud or branch, or in overgrowths 
caused by pruning, and takes place during August or September. 
The injury to the plants is caused by the larve which girdle the 
trees, and so weaken them that they often fall with the wind. 
It was noticed in observing the habits of the beetles that they: 
are external feeders, which suggested the possibility of employing 
arsenical poisons as a means of combating this pest in the nursery. 
To ascertain the effects of these insecticides upon the beetles, 
numerous experiments were made which showed conclusively that 
thorough spraying, with an arsenical poison, of poplar and willow 
plantations about July 15th will materially reduce the number of 
beetles and thereby lessen the number of eggs deposited in the 
trees. Experiments are now being conducted to determine the 
actual value of this treatment for field use. 
2 
DEPARTMENT OF HORTICULTURE. 
Bordeaux injury.— Under some conditions bordeaux mixture in- 
jures the fruit and foliage of fruit trees sprayed with it. A study 
of bordeaux injury of this fruit in the State at large showed: 
That in 1905, 70 per ct. of the orchards sprayed had been in- 
jured; that an excess of lime did not prevent the injury; that in 
some orchards spraying did more harm than good; that there had 
been similar losses in past years; that the use of power machinery 
increased tlte injury; that wet weather gave favoring conditions 
for injury; and that some varieties are more susceptible to injury 
than others. Experiments on the Station grounds proved that 
bordeaux mixture causes the trouble known as “spray injury.” 
In these experiments injury seems to follow the first shower of 
a 
