The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1901-03-28

structure of all living organisms. 1t is
not only the agent which makes possible
the mobility of other constituents of the
plant, conveying them from one location
to another, but it enters in large pro-
portion into the structure of the organ |
ism itself. Consequently plants and |
trees at all times hold a great volume of |
water, the supply of which is constantly |
replenished by the water taken up by |
the roots and as constantly depleted by |
the moisture given off into the air by |
means of Transportation. 1t is these guam
titles that we require to know something
definite about.
Experiments with the sugar cane to
determine these quantities have been
carried on by the writer at the Hawaii
an experiment station. The specific pur-
pose was to determine the volume of wa
fer required by the cane at different
stages of its growth, and to come at a
rational mode of irrigation. The expert
ment was carried out as follows: Two
tubs were used, having perforated bot
TOMS over which pieces of linen were
laid to prevent the soil from going
through or filing up the perforations.
One hundred and twenty-five pounds of
| similar soil We're put into each tub. The
tubs were then set into galvanized iron
rams containing water. The water was
kept up to a certain level. which level
between the soil in the tubs and the wa
ter in the pans. The pans were careful
ly covered with moisture-proof oil-cloth
to prevent any escape of water except
ing through the tubs. The volume of
water taken up by the soil in the tubs
and given off was daily measured and
recorded and an equal volume restored to
the pans. The volume of water that the
soil could absorb and contain-that is,
ha poaa NJ abSnrntiVa
was 49, per cent of it's own weight. In
tub No. three pieces of sugar cane
were planted when the experiment was
begun. and nothing in tub No. l. after
which the water given off by each tub
was daily recorded for the following six
months. During the first twenty-six
days the two tubs gave off like volumes
of water, each one evaporating during
that period 1920 grams, or thirty-one
pounds. After the twenty sixth day tub
No. g. in which the cane was planted.
began to give off more than tub No. l,
containing soil only.
1.-The weight of the cane grown in tub
No. 2 by the consumption of 1870 grams
of water was $3.50 grams of water-free
material, consisting of roots, Bis grams;
stems, 53.S grams; leaves, 1882 grams.
These figures show that in order to form
one pound of water-free substance the
cane organism transpired 1878 pounds Of
water"
SALTS IN SOIL
| Mr. Maxwell discusses at some length
the matter of salts in Hawaiian soils
and waters, saying:
THE waters of the Hawaiian Islands
are of excellent quality, provided they
do not come in contact with the sea in
flow or with soils having high contents
of salts, due to the overflow of the sea
ot ,lta Ja
ties however, contamination by sea wa
ter has gone so far that the water is
destructive to vegetable life In most
instances the deleterious agent is COM
mon salt: in others there is mixture of
are most injurious to plant life, and, In
common salt with bittern salts. or chlor-
id of magnesium and lime. The latter
| lowlands, lying almost level with the
sea, where there are no means of get
ting these salts removed, their impreg-
nation renders the soil useless
| "a considerable portion of the water
supply for irrigation In the Hawaiian
Islands Is derived from the underground
flow. Ground waters as a source of sun
| ply for irrigation present more elements
to be considered than the waters of riv-
ers or surface waters, which latter are
almost invariably suitable for Irrigation
uses. Ground waters on account of the
considerable proportions of certain high
lily desirable elements they contain may
be very valuable for application to crops.
On the other hand because of the large
amount of substances inimical to plant
life held in solution, they may be quite
unfit for irrigation. Numerous instances
of the unfitness of some waters for plant
use are furnished by other countries and
special examples have been found by the
writer upon the Hawaiian Islands.
"In soils containing over OBS per cent
of salt, unless liberal allowance Of
some vital element such as nitrogen, is
present to force on the growth. the su-
gar cane is liable to suffer-
RICE AND SUGAR CANE.
THE chief crops,' writes Mr. Maxwell,
that are grown by the aid of artificial
irrigation in Hawaii are rice and sugar
cane. The lands used for rice are the
lowest flats found at the outlets OF val
leys and close on the sea. Irrigation is
practiced upon all these lands, but no
means of determining the volume used
per acre have been adopted and data are
not at hand bearing on the question.
Sugar production is, relatively speak
ing, a recent matter so far as the pres
ent volume of production is concerned
So late even as 1880 the output is record
ed as being $1,000 tons, while the produc-
ton last year dS99) was 2S2,S 07 tons The
part played by artificial irrigation in
the production of the Hawaiian crop Is
seen from the following statement: Su-
gar grown by natural rainfall 1882 tons:
sugar grown by irrigation, 1885, 25 tons.
1.-THE area to which water Is artificial
ly applied is yearly increasing, and in
two years more than two-thirds of the
crop, which is also vastly increasing, will
be grown by aid of irrigation.
1.-THE richest lands upon the islands are
those lying toward and a little above sea
level. In most of the districts, however,
the rainfall over the low-lying lands, and
especially upon the leeward side, is ut
terly insufficient to produce the sugar
crop. Until the practice Of irrigation was