The Hawaiian star. [volume] (Honolulu [Oahu]) 1893-1912, 1901-12-06
RAINFALL AND FORESTS WITNESSES KICKED
THE RELATION THEY BEAR TO
EACH OTHER
Forests, Especially Those with Dense
Underground Sustain Springs They
Exercise an Equaliziug Influence

G. II. Kluegel i'm a recent communica-
ton to the Hawaii Herald thus discuss
es forests and water supply
Recent articles In the Planters
Monthly on the subject OF forests must
leave the reader in doubt about the
facts and the conclusions To be drawn
therefrom.
1t appears to be a frequent error TO
mistake cause for effect. Vegetation is
said to be the cause Of rainfall. when
II is the effect The well known fact
that generally on these islands there is
a heavy rainfall in the upper forest re-
gion while on the bare plains below the
rainfall is small does not prove that the
| forest Is the cause Of rain. Generally
forests viii not grow with less than
thirty inches of annual rainfall
Forests, especially those with dense
underground, sustain springs. They
retard the flow of water to the streams
and delay the melting of snow and ice
/ The flow of streams is therefore equal
| lied. Sudden freshets are less frequent
and periods of low water are shorter
As there is practically the same amount
of evaporation from a forest area as
| from cultivated or bare areas. the total
run-Off is the same in all cases.
In forest water is more readily alb
sorbed and the absorption is longer
continued because the surface run-otf
Is retarded.
The water supply of Oahu is obtain
ed mostly from springs and wells. The
source of the water is in the large for
ested mountainous area in the middle of
the island. Continued rains on this
area cause little surface run-off. The
stream beds seldom carry much water
except from lower springs that flow
from the same general source.
1t is therefore of vital Importance
that this forest be preserved. This can
readily be done. and is already being
done. In no other way can this bounti-
full water supply be stored for the need
ed irrigation.
In Maui and Kauai the conditions are
similar to Oahu
| on the Island of Hawaii crops are
generally not dependent on any forested
area, Forests have remained and they
should remain until a better use can be
made of the land. Such better use In
Hamakua and North Hilo has been well
stated in the report. of one of the men,
| bers of the Committee on Forestry
| The rainfall on the forest area OF
Olaa can practically be utilized only on
| that area There is no spring nor
stream of any size. Should deforesta-
ton reduce the rainfall, that would be
something of an improvement. There
Is no possibility of this area becoming
less useful by it's deforestation.
In Europe, Notwithstanding deforesta'
ton, fertility has increased. While this
is owing to better farming, there has
been practically no decrease in the rain
fall to prevent the increase of produc
tiveness.
The sea and the Typographical fea
lures of a country have much more ef
feet on rainfall as caused by changes o
temperature than the vegetation.
The producing effect of tn
mountains of Oahu which has bee
much observed at the head of Nuuan
| Valley Is far greater than the erect {
a forest Neither the presence of forest
nor their absence causes the diherenc
! of rainfall between Upper Nuuanu an
| Eva plantation.
, One writer thus refers to the Sacra
= mento river: "Ships of moderate ORA
had no difficulty to ascend as far a
A Maryvlle," and that the destruction
: forests is entirely responsible FOR II
q rivers low water mark in summe
n time"
- The fact is that formerly the So
Y cramento was a deep tidal river Du
n ing the dry months of autumn, at lea
a the water surface was practically
y sea level and without any tributal
= whatever there would still have been
e deep. navigable channel. In later yea
the greater part of the channel WI
filed with debris, mostly from &
hydraulic mines.
II A recent State report on forests, ba
10 ing its conclusions on records beginni
IN in 1925 says: And we are forced to I
M conclusion that it is impossible to ira
no any effect, either upon rainfall or tel
= perature. due to the distribution of
to forests"
nd "The result of these studies must
/ regarded as demonstrating that the
m cords of rainfall and temperature fail
k show any difference in climate betWe
re forested and deforested portions of
State which may with confidence be
e. crlbed to the influence of the forests,