1016 
on Nob Hill and Fruitvale varied between 
20 degrees and 23 degrees* The reports 
from these districts showed much uni- 
formity and many readings were made 
from reliable instruments. Moxee varied 
only a degree from North Yakima, and 
Sunnyside, which more often corresponds 
with Moxee, was even warmer. An inter- 
esting problem is here presented and its 
solution may disclose some interesting 
facts. The following is suggested by ob- 
servations this spring: 
A study of a topographic map of the 
region should be made in order to appre- 
ciate the situation. The Yakima valley is 
inclosed on all sides by mountain ranges 
varying from 2,500 to 3,000 feet in height 
and higher in the Cascades to the west. 
Access is had to the valley by two gaps 
on the north and one on the south. Noc- 
turnal air drainage will always be from 
north to south under normal conditions, 
following the slope of the land, and ob- 
servations show this actually to be the 
case. Fruitvale and the northern slope 
of Nob Hill are the first to benefit by the 
northwest breeze from the Naches can- 
yon, a&S they lie directly in its course 
and in close proximity to the Nachez 
gap, from which it issues. There may 
be a similar breeze from Selah gap, a 
little to the eastward, but observations 
do not cover this point, nor are there 
any extensive orchards in line with Selah 
gap to benefit by such a breeze if there 
were one. 
The Naches valley above Naches gap 
forms a natural reservoir for the air 
drainage from a vast mountainous area, 
and it is natural to conclude that when 
the convergent air is expelled into the 
Yakima valley below through the outlet 
formed by Naches gap a mixing of the 
air and possibly an adiabatic warming en- 
sues, which would account for the com- 
* This statement was based on temperatures 
as recorded at Scudder’s station, located at the 
mouth of the Moxee valley. Had we more sta- 
tions in the valley southeast of Scudder’s I hbe- 
lieve they would show that minimum tempera- 
tures do not vary a great deal from those re- 
corded at Bender’s station in North Yakima 
The district at the junction of the Moxee and 
Yakima valleys, represented by the Scudder sta- 
tion, is probably the coldest in the region above 
Union gap, due to the air drainage from not 
only the Selah and Naches valleys, but also 
from the Upper Moxee. 
ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 
paratively higher temperatures encoun- 
tered in the region lying directly in its 
path, as at Fruitvale, and the compara- 
tively lower temperatures in the Fair- 
view and Moxee districts, which lie sev- 
eral miles southeast of Fruitvale. 
The Weather Bureau station is located 
in the city of North Yakima, and, there- 
fore, between the two districts under dis- 
cussion, Fruitvale being northwest of the 
city and Fairview and Moxee southeast. 
The thermometer at this station strikes a 
pretty fair mean, for while Fairview is 
often two degrees and Moxee five degrees 
to eight degrees colder than the North 
Yakima station, Fruitvale is usually a 
few degrees warmer. As the breeze from 
Selah gap spreads out and flows across 
the valley it loses its force, its tempera- 
ture is lowered by radiation, and with 
further southeastward movement its 
character is changed from a protective 
wind to a more or less destructive one. 
On the morning of the 11th, when the 
conditions in these districts reversed, a 
freezing wind was blowing from the south 
and southwest, having blown from this 
quarter throughout the night. There was 
no counter breeze from Naches gap, and 
the minimum temperature reported from 
the Naches valley above, a district from 
which comparatively high temperatures 
are usually looked for, was 22 degrees. 
Thus it appears that strong connection 
exists between a reversal of the customary 
wind direction and a reversal of tempera- 
ture conditions in the several localities 
under discussion. 
Boise 
Epwarp lL. WELLS 
(See diagram C) 
The Boise valley is well suited to the 
growing of such fruits as apples, pears, 
prunes, sour cherries, and common ber- 
ries. Some fruit has been grown in the 
valley for many years, but it is only with- 
in the last few years that scientific fruit 
growing on a commercial scale has be- 
come an important industry. 
While the entire region is more or less 
subject to spring frosts these frosts are 
rarely sufficiently severe to cause wide- 
spread damage. For this reason, prior to 
