done in other countries with the same characteristics both of soil and 
climate. (See American Meteorological Journal, 1891, Vol. VII, p. 
41.) 
WIND. 
The effect of the wind on vegetation is quite various. Among other 
influences, we note the following: 
(a) It is considered that the mechanical action of the motion of the 
stems and trunks and stalks is to strengthen them and to stimulate 
the growth of the roots. 
(6) The winds distribute the pollen and the seed and thus assist, 
or even entirely control, the preservation of the plant and its geo- 
graphical distribution. 
(c) The wind renews the air, so that a superabundance of the 
hecessary gases is then assured. 
‘(d) During cool, clear nights a wind, by renewing the supply of 
heat, prevents the formation of frosts by radiation. 
(e) On dry, cold, frosty nights the wind, by its dryness, evaporates 
any frost that may be formed upon the plant, but does not prevent 
the freezing of the plant as a whole. 
(7) By bringing moisture, fog, and clouds from the lakes and 
ocean up over the fields and forests the wind prevents frosts and 
favors the growth of delicate plants on the leeward side of large 
masses of water. 
(g) Gasparin states that when a cold, dry north wind suddenly 
blows over plants in active growth they become stunted, and it is 
said that the plants have taken cold. A similar phenomenon occurs 
in the valleys of California. 
Gasparin’s description is as follows (Cours d’Agriculture, 2d ed., 
138520. 202) : 
In, the valley of the Rhone the north wind produces a lowering otf 
the normal temperature of about 7°; all the vegetation is more or “less 
involved if after several days of calm, clear weather, during which 
the heat has increased, such lowering of temperature is experienced. 
Even, if there has been no frost and the plants have preserved their 
vitality unimpaired, it produces a singailar effect on them; their growth 
stops and they remain stunted. Our agriculturists describe this con- 
dition by saying that the plants have “taken cold.” The leaf buds 
which put out later resume their growth, but the leaves and branches 
experiencing this cessation of growth never entirely recover from it. 
This accident is especially injurious to natural and artificial meadows 
and to the leaves of the mulberry tree. As regards the meadows, 
the best thing to do is to hasten the mowing of the grass, in order to 
gain time for the succeeding crops to prosper, and for the mulberry 
trees it is advisable to await the development of new buds. 
The more rapid these dry winds are the more they hasten the drying 
up of the soil. After they have prevailed for several days the earth 
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