DIVISION OF FORESTRY. 607 
productions upon irrigation, the water for which is derived from the 
mountain streams and more rarely from artesian wells, both of which 
sources are fed by the rains and snows which fall upon the forest- 
_covered mountain sides and gradually find their way to the plain 
below. As has been repeatedly stated and explained elsewhere, and 
proved not only by experience but by actual experiment on a large 
scale,* the forest cover regulates and beneficially influences the ra- 
pidity with which these precipitations are carried to the plain for 
utilization on agricultural lands. 
After entire cantons had been impoverished by the action of tor- 
rents, due to deforestation, the French Government found it neces- 
sary to interfere, or rather, interference coming too late, to assume 
or aid in the work of reforestation. The construction of vast reser- 
voirs to retain the surplus waters in flood time, the construction of 
stupendous dams, and the embankment of river courses were first 
suggested as remedies for the evil, just as our ambitious engineers 
are now proposing. But these were soon found not only to be imprac- 
ticably costly but to create new dangers, perhaps greater than the 
old, since the mountain reservoir might burst at any time and the 
embanked river was certain to rise to a dangerous level above the 
surrounding plain. The wiser plan of reforestation was finally re- 
sorted to, with results which have now proved the wisdom of that 
measure. Austria and Italy, under similar conditions, after sending 
commissions to France to study the effects of reforestation, have 
begun similar work. Since the year 1860, the French Government 
acting in co-operation with the local communities, it is estimated that 
over 250,000 acres of mountain lands have been reforested, at a cost of 
* There has been of late much discussion as to whether or not there exists any rela- 
tion between forest cover and rain-fall, and records of meteorological data have been 
brought forward to show that in Ohio, for instance, deforestation, if anything, had 
the effect of increasing rain-fall, while no increase of rain-fall has been noticeable in 
Kansas since tree-planting began there. How little value is to be attached to the 
use of the records on hand for showing any interrelation between tree-growth and 
rain-fall may be inferred at once from the fact that these same records can be and 
have been used to prove exactly the opposite influences, showing, without reference 
to the causes, that an increased precipitation in the Western regions is observable. 
In fact, outside of the special observations which have been made in Germany, and 
less satisfactorily in France, there are no data at hand for definitely proving either 
the existence or the absence of forest influences on the humidity of the atmosphere. 
This influence, as probably most forest influences, is of local character; the extent 
- ag it is felt is limited, and can be measured only by special records for each 
ocality. 
It is not unreasonable to believe that the influence of a forest area upon rain-fall 
may be exactly the opposite from beneficial to the plain beyond, and yet this does 
not alter the proposition that an influence exists. If, for instance, a large uninter- 
rupted forest area were lying towards the side of the rain-bringing winds, it is 
possible that the condensation to which the cooler and relatively moister air above 
the forest would give rise might drain the clouds before they had passed on to the 
plain, and thus a partial removal of the forest growth might be promotive of moist- 
ure on the plain. The reasoning that a-large, dense forest cover of the soil, suffi- 
ciently large and dense to create a considerable difference of temperature and 
with it of moisture in its air strata, should exert an influence upon precipitation 
seems to be sound; but while the actual existence of such influence seems to have 
been locally observed it is not, as a general proposition, proved or disproved. 
That the transplanting in Kansas should have been sutticient t create such differ- 
ences of atmospheric conditions as are necessary to exert an influence upon rain 
clouds is at least doubtful, and the reasons above given for the increase of rain-fall, 
if any, seem more tenable. . 
Meanwhile, the well-proved mechanical influences of forest-growth on the even 
distribution of the fallen rain through the year in springs, brooks, and rivers out- 
weighs all other considerations for practical purposes. ; 
