Oxford Democrat. [volume] (Paris, Me.) 1833-1933, 1920-11-23
seaweed as a Fertillzer.
VALUABLE NATURAL SOURCE OF
POTASH.

& VALUABLE NATURAL SOURCE OF
Eighteen years ago the Maine Agricul-
tursl Experiment Station published Q
bulletin on seaweeds common along the
coast Of Maine. This publication is now
out of print. As inquiries chiefly from
correspondents along the coast continue
to be received few Of the. more impor
tant points relative to the use OF sea-
weeds az manure are here presented.
The principal deeper water sesweeds
are two species of Lansindrid, the ribbon
weed or kelp; and the broad ribbon
weed, or broad-leafed kelp, frequently
called DEVILS apron. Perhaps three
fourths of the shore weeds covering the
rocks between tide marks are two spe-
cies of Fucus, the dat-stalked rockweed
and the round. stalked rockweed. The
specimens collected In the winter month
carried for the most part much more
nitrogen, phosphorio acid and potash
than the same species collected In the
summer season. On this account 1t is
advisable to collect the seaweeds during
the winter months, and II 1t is not con-
venient to apply them at once to the
fields, they may be stored In large heaps
until spring.
While the different species Of seaweeds
probably differ in composition, not
enough samples have been examined to
clearly indicate that fact. Winter col.
lected seaweeds, both kelp and rock
weed, carry about 80 per cent of water,
4 per cent nitrogen, Il per cent phos-
phoric acid, g per cent lime, and g per
cent potash.
On account Of the large water content
and consequent weight OF seaweeds,
transportation far inland is not profit
able. A part OF the water can be re-
moved by spreading out thinly on the
shore and allowing exposure to q hot
sun for few days, but 1t is question
whether this practice is economical oD
account of the increased labor involved,
and If the material is leached by rains
after it has become partially dried part
of the fertilizing constituents are lost.
Seaweeds decompose rapidly SO that
their fertilizing constituents become
speedily available. AS they have no
power of absorbing liquids there is no
advantage In composing them. They
are best applied directly In the green
state.
Seaweeds produce their chief effect the
first season. This adds rather than de-
tracts from their value az q fertilizer,
since when they can be obtained at ell,
they can usually be had one year ss we'll
as another, and can be applied annually.
The analyses shows that ssaweeds are
not evenly balanced manures. They con-
tain relatively considerable amounts of
nitrogen and potash, and but little phos.
phoric acid. Consequently land dressed for
along time with sesweed alone becomes
exhausted in phosphoric acid unless q
large excess of manure is added which
would be wasteful of the nitrogen and
potash. Excellent results have been OBJ
tanned by using phosphates with these
mauures. Dissolved bone or acid South
Carolina rock may be used, 800 to 500
pounds to the acre, with 20 to 80 tons Of
the fresh seaweed.
With most crops the best results are
obtained by applying the fresh material
In the spring and either plowing or hsr-
rowing 1t into the soil, but potatoes and
some root crops, like the sugar beet, are
said to be injured in quality by spring
applications. This is probably due to
the large amounts of chlorides of msgne-
nesis, sodium, etc, they contain, as It is
we'll known that these substances have
the effect of depressing the amount of
starch in tubers and thereby impairing
the quality. Farmers who use seaweeds
for potato manure can overcome this
difficulty by applying it to the fields in
the fall before planting In the spring. In
this way potatoes of much better quail
ity, 1t is claimed, are grown than by ap-
plying the seaweeds at planting time.
In some localities sesweed is applied
"a q top dressing to moving fields, but II
applied fresh In the summer season care
must be taken not to apply too thickly,
as there is danger Of killing out the
grass, especially on new fields. Some
farmers prefer composing for this pur.
pose with stable manure in order to 6pe
the material 90 that 1t will spread more
evenly over the field. Il is probable that
the addition of acid South Carolina rock
to the compost would greatly increase
it's value and aid in holding the ammonia.
If the fermentation 10 carried very far,
land plaster or muck should be spread
over the heap to prevent ammonia from
escaping.
Eel grass is not true seaweed, but
belongs to the pond weed family, group
of mostly fresh water plants. Eel grass
carries about the same amount of plant
food as the sesweeds, but tits only with
difficulty that they can be made avail
able. Eel grass will hardly rot any here
either In the soil, in the hog pen, or ir
the manure or compost heap. Wber
dried 1t is used as filing for cushions
mattesses, etc. But the plant has no ag'
| ricultural use.
A good dressing for potatoes would be
had by applying 20 tons OF winter CO.,
lected green seaweed, 400 pounds of acid
phosphate, and 100 pounds of nitrate ol
soda to an acre. This would give about
100 pounds of nitrogen, of which sixth
is Immediately available; IS pounds Of
phosphorio acid; 100 pounds Of lime anC
120 pounds Of potash.
Seaweeds have, in common with com
mercial fertilizers, the advantage of free
dom from weed seeds, the spores o
fungi and the eggs of insects. To Rhode
Island, where seaweeds are quite largel!
used ss manure for potatoes, the farm
ers are almost unsnimous>in saying tha
potatoes grown on seaweed are smoothe
and freer from scab than those grown OF
stable manure.-Chas. D. Woods, Di
rector.
Il