Daily Kennebec journal. [microfilm reel] (Augusta, Me.) 1870-1975, 1896-09-09
Preventing and Lcssenins Frost Iniur.

|
upon plants and other objects. and tn
, temperature lowered below freezing NV
radiation OF heat. Radiation is mos,
rapid through a dry air accomnan,oa
> by a clear sky. Clouds or anv otha.
opstructions have tendency to retard
, II. 1t takes place more rapidly from,
the surface of plants, etc, than it doos
from the air surrounding them, so tina,
on quiet nights plants are FREQUENTLY
cooled several degrees below the tenn.
pcrature Of the surrounding air. A,
such times. also, the air arranges itso,,
according to density with the colder
heavier layers near the surface Of tho
ground. thus increasing the liability tn
INJURY of plants and trees This ia
reasonably uniform on level fields. bur
where the ground is uneven, the cool
air accumulates at the lowest points
frequently causing severe frosts on the
loWlands while the hillsides remain nm.
injured on windy nights frosts are
less liable to occur, from the fact that
the different strata are mixed and tho
temperatures kept more uniform.
Early frOSts cause great destruction
particularly to fruit growers and gar
| dcncrs. To prevent them. its is neces
sary TO diminish radiation Of heat from
| the plants, add heat To the air. drain
off the cold air. or mix the air so as to
prevent the cold layers sinking to the
surface of the ground. In level
country some means Of obscuriug the
sky by forming a smoke or d vapor
| cloud over the fields To be protected
| has been most successful. 1t is ,prac-
ticed on the level plains of the west
and northwest and in the orchards of
the Pacific coast. Heaps Of rubbish
are placed along the edge of the field,
| 50 that when the fire is lighted the
smoke and v&por will be blown over
| the surface. The material for making
tho fire may consist of hay. straw. old
| leaves. tar or any other material which
! VIII produce large quantities Of smoke
! The danger does not appear until past
midnight, consequently these heaps
should be prepared beforehand. the
Thermometer watched during the night.
and when it becomes apparent that
frost VIII appear. these should be
lighted. on the Pacific coast it has
determined that at the following tenn
pcraturcs the various crops are liable
1" frost injury after the period of fruit
setting: Apples, Is. apricots, 50, aspar-
aeus. &c. beets. -, cabbages, 15-27.
d lery, ~. grapes. IS. lemons. Is. lettuce.
l--2S. okra, 81, onions, %, peaches. 20,
pears. Is. peas, %. plums, -, potatoes.
-. radshcs, -. Strawberries. 80. and
tuluips. %.
The presence of steam and vapor in
the atmosphere is also a means of pre-
venting radiation, consequently it is
advisable to spray the fires lightly with
water. causing Il fog or Vapor cloud in
addition to the smoke. This plan is al
most certain protection on the plains,
but IN valleys it is not So useful. The
heat of the fire causes the air at the
lowest point to expand and rise. Its
place must be supplied. and the cold
air flows down the sides of the depres-
sion. settling at the bottom and en-
danScrinG not only the plants at the
lowest point but also those on the hill
side which would otherwise escape
III this ease it is necessary to provide
fires up the sides of the valleys as well
a. at the bottom. The expense of this
snudge is small and it can be profit
ably tested.
1t has been observed that frosts are
more destructive during dry time
than when the ground and atmosphere
are saturated with moisture. Conse-
Qucntly. where irrigation is practced,
turn on the water until the ground is
thoroughly moistencd. Then eVapora-
ton from the surface will saturate the
lower layers of air and greatly aid in
preventing radiation of heat from
plants and shrubs. This method has
been fairly successful in protecting
citrus groves. The irrigation should be
done at as early an hour as possible.
preferably the day before frost is ex-
pectcd. Spraying the trees with water
has been even more successful than
irrigation. especially with plants which
are not injured unless the temperature
falls several degrees below the freezing
point, for in this case the water will
freeze before the fruit is injured and in
freezing Will libcrate large amounts of
heat, thus preventing any radical
change Of temperature. The spraying
must be continued until the air begins
to warm up.
The best method of protecting from
frost is to provide thorough air drain
age for orchards, berries and garden
truck. Do not obstruct by such crops
rs corn or orchard the mouths of ra-
vines or the points from which the
cold air would naturally flow out.
Avoid putting tender plants on low
ground. especially if the field is be-
tween higher points of land Hardy
fruits may do well at these points but
the tender varieties should be placed
farther up the sides or on level areas.
Air drainage may be secured by plant
ing thick hedge halfway down the
hillside and on the upper sides. making
Il ditch. If this can be filled with
water so much the better but in any
aase the cold air coming down from the
higher levels will be carried off by this
barrier and not go further down to in
ure the crops. 1t is best, however. to
plant these low lands to crops which
mature before frost comes. and keep
ruits and tender vegetables on higher
areas, or at least those that have a
borough circulation of air This mat
er of air drainage is being carefully
studied and is of paramount import
'nce. 1t is much easier to. by this
means, lessen the liability of frost than
Fl nv oil a,.