Albuquerque morning journal., 1922-04-19
BY J. c. KIRCHER,
u. S. Forest Service.

U. S. Forest Service.
Drainage of the Rio Grande val
ley will not permanently increase
the agricultural prosperity of this
region. according to District For
ester f. c. w. Pooler. of the Unit
ed States forest service, unless the
watershed of the Rio Grande is
Kept timbered and the ranges are
kept in good shape.
improving the conditions of an
irrigated valley" said Mr.. Pooler
most people fail to appreciate the
fact that it is just as important to
watch the timbered watersheds as
1T is to make improvements In the
valley itself. without properly
handled watersheds, it is futile to
expect that storage facilities and
drainage in the valleys will per-
manently keep them productive.
I'm the southwest most of the
snow and rain falls in the noun
tains. If IL falls on bare, steep
slopes, snow causes slides which
may denude timbered areas below
Rain on such slopes runs off rap
idly, taking much soil with 1t and
making deep gullies. In either
case disastrous floods which carry
much soil may come down the
mountain sides into the rivers. In
addition to the damage caused by
such floods, the soil is carried into
irrigation reservoirs where 1t set
Ties and ultimately fills them up.
SNIhn rnn1a 81 l..
oughly alive to this sitting process,
and Is much concerned over it.
Sooner or later, depending upon
the amount of overgrazing and
timber denudation on watersheds.
dredges must be put to work clean
ing out such reservoirs as Elephant
Butte and Roosevelt. The fire.
quency Of dredging is dependent
largely upon the way the water
sheds are handled"
But when these watersheds are
kept timbered and are not over
grazed, what can be expected?
Trees Check Erosion.
=. Perhaps the most obvious rela-
tlon that exists between forests
and water is the tendency of the
tree cover to check erosion. Tho
leaves and branches of the trees
prevent the rain from beating upon
The soil as 1t does in the open; the
cover which they afford delays the
melting Of snow in the spring; the
upper layers Of the forest soil act
as an enormous sponge that alb
serbs large quantities of water
which. in turn. are passed on to
the great reservoir of mineral soil
beneath and finally, the surface
cover of stumps, fallen twigs.
branches and even whole trees,
acts as a mechanical obstruction
TO prevent rapid run-off. The sur
face run-off from forest areas Is
less, both in total amount and IN
velocity, than that from similarly
situated interested areas. The
sleeper and more rugged the to-
Biography, the more marked Is this
contrast.
In. hilly country some. erosion, IL,
of course, Inevitable under any con-
ditions. When the soil cover Of
trees, underbrush and litter is kept
intact. however, this is more often
beneficial than otherwise, since
only the lighter soil particles are
washed away, to be later deposited
in the level lands below, adding to
their fertility. But when this pro-
tective cover is interfered with,
whether by fire, destructive lum-
boring, overgrazing or intudicious
clearing of land for agriculture, the
proportion of coarser, infertile ma
terials washed away increases
greatly and transforms erosion
from q constructive into danger
ously destructive force, difficult Of
control and capable of doing un-
told damage.
Important To Water User.
From the standpoint of the water
user, the tendency of the mountain
forests to prevent erosion is of the
utmost importance. Wherever stor-
age reservoirs must be used, whethe. I.
for municipal supplies, irrigation
or water power, they are exposed
to the ever-present danger OF sitting
up. Every bit of soil brought
down by the streams and deposited
in them reduces their capacity and
consequently their effectiveness by
Just so much. This sedimentation
is serious under any condition, but
doubly so when. as not infrequently
happens, no other satisfactory dam
sites are available and, the reser-