96 
thé more restricted tracts of suitable river 
bottom soils. 
BE. R. LAKE, 
Oregcn State Boaid Yorticulture, 1911. 
See also article on “ADAPTATION OF Va- 
RIETIES TO ENVIRONMENTS.” 
Voleanic Ash and Apple Culture 
The question is often asked, “Why is 
the Pacific Northwest becoming so famous 
for the production of apples?” There are 
three general answers to that question. 
The first is that the latitude is in the 
great apple producing belt of the world. 
Even where the latitude would seem not 
to be far enough north the altitude of 
the hills and mountain ranges often com- 
pensates for the distance south, and gives 
cool nights, and a temperature favorable 
for the growing of the best fruits. 
Second, in a large part of this country 
there is during the day a bright sunshine 
and at night a cool air, both of which tend 
to give color and flavor to the apple. 
Third, the character of the volcanic 
ash soil, of which a large portion of this 
region is built, is favorable for the growth 
of the apple tree and its fruits. 
The following are the principal soil 
elements necessary to the growth of the 
apple tree: 
1. Nitrogen. 2. Salts of lime. 38. Salts 
of potash. 4. Salts of phosphorus. 5. 
Salts of iron. 
In the arid regions the soil is rich in 
mineral substances, because the volcanic 
ash, rich in these elements, has never 
been leached by heavy rains. This soil 
may be improved by the addition of barn- 
yard manure or the growing of cover 
crops like clover, alfalfa, or vetch, to 
supply humus and nitrogen. In the hu- 
mid regions where the rains of centuries 
have leached the soil and where there is 
a large vegetable growth it is sometimes 
necessary to supply mineral fertilizers. 
However, the general character of the 
soil in the inland region is volcanic ash, 
rich in lime, potash, phosphorus and iron. 
Further, there are numerous valleys, 
with good drainage systems that are pro- 
tected from heavy winds by hills or moun- 
tain ranges, and in these valleys orchards 
can be successfully grown without dam- 
ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 
age to the fruit from storms. In these 
valleys irrigation is successfully carried 
on and the melting snows in the moun. 
tains furnish abundant water . 
In the bottoms the soil is sometimes a 
deposit of sand, gravel, and wash from 
the hill sides, favorable for the deep root- 
ing of trees. On the uplands it is gener. 
ally a fine ashy substance, into which 
the roots may penetrate to considerable 
depth. In places the wind has carried 
it for ages, and deposited it in coves, shel- 
tered places, and behind the hills, so that 
it may be under such conditions, 50 to 100 
feet deep. However, in such deposits the 
tendency is, under irrigation, for the soil 
to puddle and become impervious to the 
water, which prevents aeration, and the 
percolation of water to a depth sufficient 
for the root development of the large 
trees. In such a case the best remedy 
is the growing of alfalfa, with its strong 
root system, which penetrates below the 
puddled stratum, lets the water down, 
aerates and nitrogenizes the soil and 
opens up a new world of food for the 
roots of the trees. In some places there 
are strata of hard pan, which must be 
broken up with dynamite; but in general 
a volcanic ash region is a region most 
favorable for the growing of apples. 
GRANVILLE LowrHer 
WEATHER CONDITIONS 
The liability to frost is one of the 
things that must be kept in mind in se- 
lecting the most favorable site for an 
orchard. Reference is made in the article 
on frosts to the Thermal Belt where there 
is not likely to be injurious frosts during 
the seasons of blooming and fruiting, (See 
Frost.) In this connection we would say 
that there are three natural conditions 
that protect from frost. The first is ele- 
vation; the second, air currents; and the 
third is the modification of temperature 
by the warmer atmosphere from large 
bodies of water. 
Elevation 
By elevation, we do not mean the dis- 
tance above the level of the sea, but rel- 
ative distance above the surrounding 
country. For instance, if the general 
level of a particular portion of the country 
