8 
COLORADO EXPERIMENT STATION. 
For the later sprays, a nozzle producing a fine mist is desir¬ 
able. A nozzle of the double-vermorel type, arranged in such a way 
that the direction of the nozzle can be placed at any angle with the 
spray pole, is wanted. The size of aperture wanted in the nozzle 
cap will depend upon the pressure maintained. The higher pres¬ 
sures can be directed through larger apertures and still produce as 
fine a spray. Higher pressures economize upon material and time, 
and under ordinary conditions are most desirable. 
In the experiment conducted upon the orchard of Mr. G. W. 
Marchant, of Fruita, two sprayings with Swift’s arsenate of lead (12 
pounds per 200 gallons) applied at the times indicated in the above 
table, and in a thorough manner, produced 98 per cent winesap, 95.6 
Ben Davis, and 91.8 Jonathan apples free at picking time from all 
worm holes. Picked, unsprayed Jonathans in a block in the same 
orchard gave only 43.1 per cent free from worm holes, and 49 per 
cent of the apples, by actual count, originally borne by the trees, had 
fallen to the ground, 96 per cent wormy before picking. Onlv 15 
per cent of the total crop of sprayed Jonathans fell to the ground as 
windfalls, and 74.1 of these were perfect apples. The apples in the 
sprayed plats were treated with a repetition spray following a heavy 
rain, though by comparison with plats left untreated with such spray 
it was found that the additional or repetition spray was unnecessary. 
The complete details of this summer’s experiments and obser¬ 
vations upon the codling moth will be available in a special bulletin 
issued by the Colorado Agricultural Experiment Station, which bul¬ 
letin is now under preparation. 
HOWARD SCALE. (Aspidiotus howardi Ckll.) 
This pest is one of greatest importance to the pear growers of 
parts of Colorado. Besides the pear, it is known to infest prune, 
plum, apple, almond, and certain shade and forest trees. 
The life history of the insect was partially worked out during the 
year and experiments conducted showed the insect to be possible of 
cheap and complete control by spring applications of the lime and 
sulfur wash. 
As a bulletin is also soon to be issued upon this pest and its rem¬ 
edies, based principally upon this season’s investigations, details of the 
work on the insect may be ommitted in this general report. 
PEACH TWIG-BORER. (Anarsia lineatella Zell.) 
Introductory —Experiments conducted at Palisade have demon¬ 
strated the great value of arsenate of lead against the twig-borer of 
the peach, which caused considerable damage to the peaches in this and 
other localities of Western Colorado. 
Former recommendations for the control of this insect have been 
for spring applications of lime and sulphur washes. This has in fact, 
been a most successful treatment, but the use of lead arsenate against 
the twig-borer of the peach is destined to meet with equal popularity 
when its efficiency, cost, and convenience of preparation and application 
are considered. 
