MINNESOTA STATE HORTICULTURAL SOCIETY. 161 
ae and the preservatio no the natural forest. 6th. The adop- 
of the plan of protecting orchards and small fruit grounds 
a belt of evergreen trees. 
Ts compliance with the conditions in the first proposition may be 
noticed the introduction of the Red Astrachan, Alexander, Duchess, 
and the testing of numerous other varieties from similar sources. 
In complying with the terms of the second proposition, the process 
of acclimatizing by the process of reproduction is laborious, and 
considerable time must necessarily elapse before the desirable, le- 
gitimate results van be accomplished. In promise of its eventual 
fulfillment may be cited the production from seed of a number of 
varieties in Minnesota, Iowa and Wisconsin, possessing considera- 
ble constitutional vigor or hardiness, which may serve as the founda- 
tion for the reproduction of other varieties possessing still greater 
inbred constitutional adaptation to the climatic influences with which 
they have come in contact. 
The requisite conditions specified in the third proposition have 
promise of fulfillment in the past and present efforts of earnest and 
eminent horticulturists to obtain by hybridizing, varieties of apples, 
the trees of which will be as hardy as the crab, and the fruit of 
which shall partake of the size and flavor of the best and most 
promising varieties of apples now in cultivation. 
The requirements of the conditions of the fourth proposition may 
be fulfilled by the general adoption on the part of orchard growers 
of the cheap labor system of sowing rye, millet, Hungarian grass 
or buckwheat in the latter part of the month of July, and allowing 
it to remain on the ground through the winter, and thereby pre- 
venting the alternation of freezing and thawing which has pro- 
duced so much injury to the roots of trees and small fruits. 
In the fifth proposition, for the purpose of modifying tempera- 
ture, increasing rainfall, and to retard the evaporation of moisture 
from the soil, and to break the force of winds, efforts should be en- 
couraged for the more general planting of trees in the form of for- 
ests and timber belts upon the boundaries of farms, and at least 
one line of trees upon each side of the line of railways, and two 
lines of trees upon each side of all public highways. 
The sixth proposition requires for its fulfillment the adoption of 
the plan of enclosing all orchards (which are not favored by natural 
forest protection,) with belts of evergreen trees ; hence it is impor- 
tant that such facts as have a bearing upon the supposed advantage 
to be derived from such protection should be brought to notice. 
It is conceded that ‘cold air in motion has the property of ex- 
tracting heat in proportion to its velocity.’’ In illustration of this 
principle we will suppose that when the mercury in the thermome- 
ter is below the freezing point, a person may emerge from a forest 
or place where the air is not in motion, and enter a treeless plain, 
or place where the air is in motion at any given velocity, and there 
is apparently a sudden increase of cold; the apparent lowering of 
temperature being attributable to the increase of the extraction of 
heat from the physical system, caused by the moving atmosphere. 
In this instance there is not only increase of loss of heat by extrac- 
tion, but there is also an accelerated loss of moisture by exhalation 
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