76 BULLETIN" 479, IT. S. DEPARTMENT OF AGRICULTURE. 
into the original container for several minutes. To avoid boiling, 
a naphtha soap may be used, but the quantity of soap must be 
doubled and the water must be soft (rain water). This is the 
stock solution and it must be diluted with water before using, thus : 
To each 2 gallons of water add 1 gallon of the emulsion in the fall, 
and one-third of a gallon of emulsion in the spring. The size of 
the spraying apparatus will have to be determined by the size of 
the nursery. In most of them a knapsack sprayer will probably 
be most satisfactory. Using potash soaps and warm solutions, well 
strained, will prevent clogging of nozzles. 
The other standard aphid remedy is 40 per cent nicotine sulphate, 
1 part in 1,000 to 2,000 parts of water, with fish-oil or laundry soap 
added at the rate of 1 poimd for each 50 gallons of the spray 
mixture. 
PIXE-TIP MOTH. 
A pine-tip moth has been injuring the western yellow pine at the 
Bessey Xursery, Nebraska, since 1909. The small larvae effectually 
kill the succulent growing tips of these trees by boring into them. 
On account of the extensive distribution of the insect in the planta- 
tions adjoining the nursery, no effective practical remedy has as yet 
been worked out. 
BIRDS. 
Mourning doves, juncos, the Canada jay, the blue jay, the red- 
polled linnet, and the black-headed grosbeak do some damage at the 
Forest Service nurseries by scratching up the seed or nipping off 
the tops of newly sprouted seedlings to which the seed coat is still 
attached. They are held in check either by poisoning with grain 
prepared in the same way as for mice or by shooting. 
RODENTS. 
Rodents damage plants in a number of ways: By destroying seed 
in the seed beds, by digging in the nursery, by covering up plants, 
by girdling the stems, and by eating the tops, particularly during 
the winter. The white- footed mice, chipmunks, ground squirrels, 
gophers, and moles are the chief offenders. Against the first three 
and to some extent against birds several cats have been found to 
afford very good protection. Poisoning is also practiced. To be 
effective against mice and chipmunks the poison should be thor- 
oughly distributed over the area immediately surrounding the 
nursery, under old logs, brush piles, outbuildings, rock piles, or any 
other likely retreat for these animals. Poisoning is most effective 
during spring or early summer before the natural food of these ani- 
