Evening star. [volume] (Washington, D.C.) 1854-1972, 1881-01-29
ACTION OF FROST on PLANTS.
Theory Of Their Protection from
Gofd-The Effect of the Present
Cold ACKNOWLEDGEMENTS Paper by
Prot. William Saunders.

The Following paper was read before the Dis.
trict Il Columbia Horticultural Soci sty at It's
annual meeting On Wednesday, 26th inst, by
Prof VIM. Saunders. Of the Agricultural depart
nent:-
The unusual degree OF cold which has been
experienced here during this winter excites
reasonable auxietIeS with regard 70 its effects
upon vegetation, and although it Is yet rather
early TO decide upon IT'S effects on fruit or
cbards or upon vegetable growth IN general
the time is quite opportune for the conStdera.
tlOn OF some of the phenomena attending the
destruction or plants by frost
THS AMOUNT OF COLD
which plants are capable Of resisting Is quas-
taon especially interesting TO The cuitivabor OF
fruits. and it is ali the more interesting when &c
Is considered that the power OF resistance is
somewhat dependent upon circumsta nces which
are, 10 some extent, under the control OF the
cultfyator. IL frequently occurs that plant
VIII DC destroyed by q less deg.ee or ther-
mometric cold than IL had previously endured
without sustaining any apparent mi Try and
Wnen this fatality taxes place we conclude
mat the plant has been, bS some means or
other. reduced as 10 its power Of resisting cold
o.. that the afmosphericdl conditions affecting
plants are not altogether Indicated by the Their
noineter and both OF these conciusons may D..
GEUect.
am rot aware that it has ever been proved
that frost Is Beneficial TO plants, but 10 Is Well
Established fact, founded upol experience and
observation, that many OF The disc ise5 OF plauts
result from repeated inJurfe5 which they have
received from the effects OF frost or from the
extremes OF temperature during winter and
carly spring.
The exact manner In which the death or
pants Is caused by cold, although ir b IS been a
subject Of close Investigation by physiologtsts,
Is Sill apparently involved In some oo5curity
THE PHENOMENA OF PLANT DESTRUCTION By
FROST.
The commonly received opinion Is that frost
acts mechanically upon vegetable tissues by
expanding their contained fluids and Bursting
the vessels or cells in which they are enclosed.
This cannot, however, be sufficient reason to
account for all the phenomena attending the
destruction OF plants by frost. Doubtless many
pisntS, especially those OF very Succuient
nature. are destroyed by the disruption OF
tissues from expansion Of the sap in freezing.
But plants do not suffer In proportion to the
Intensity of cold as Indicated by the thermom.
eter, nee 1t Is observed that the greatest In
jury 10 vegetation does not result from the low
est temperatures. Plants will bear, without
apparent injury, zero cold In December, but
Will succumo 10 the drying winds of March,
although the thermometer may not indicate
more than ten degrees below the freezing point
In such cases 1t Is evident that destruction Is
caused by
INTENSE EVAPORATION OF THE JCICEs
Similar to what lakes pace by an intensity Of
dry air during summer. Even after winters OF
ordinary severity &c will be found that the buds
Of the grape, for example which were full and
IoGndly developed In November, have bec3me
Shrtyeed and pointed by March, unless pro-
1ected from the drying and exnau5ting Influence
OF arid. freezing breeZeS, Winter prOracCiOn or
even the hardest plants Is therefore OF great
value as affecting tie results or culture: aat in
the production OF fruits. such as the grape
straw berry. raspberry. &C., where efficient pro.
lection can readily De applied, the question of
profit or loss will frequently depend upol the
exposure or protection OF the plants duIlug the
severity OF winter.
PLANT RESISTANCE TO TEMPERATURE
AS formulated by De Candolle the power OF
GiaHta = of
First. In the inverse ratio of the quantity of
water which they coItaiu. Secondly. In pro-
portion TO the yiscldity OF their fluids. Thirdly
In Inc inverse rattle OF the rapidity With which
10 the sze OF the cells, 50 is the liability OF
plants to freeze. and: Filthy. The power of
pants 10 resist the extremes OF Temperature Ia
IN exact proportion u the amount or confined
ali Whlch the structure or the plants themselves
enables them TO contain.
-. Although the above laws may b. correct, yet
they are OF but little value Sd far as they enable
The cultivator To decide as TO the hardness OF
plant. He cannot ascertain the dimensions
OF the cells neither can he measure the Quantity
or decide upon the Quality OF the tllidS with
y htcn they are 11lied.
THE WOOD OF TIE ORANGE TREE
is TO all appearance close, compact and hard
as that OF the oak. but the orange tree IS a
tender plant where oaks are hardy. The wood
OF the willow and that or the fg tree Is l.li
aho SOFT, YET ne llg Vii nos stand 0ur walters
Whit tie Willow tTee = perfectly hardy. Vet
lht Pidcllcal deductions winch can Dc aldaaei
IRON these lawS are valuable for a,taoalrn
Psychologists have n0r been able 10 gtgs IA
r;Oad and well defined distinctions, OF any
"a nhite eApanat1On Why one plant Is harder
Than another, except 10 STATE thai | s con-
Siitnti0n Is adapted &c its natural CLIMATE Sc
itafn tnat ali plants are rendered more cap thle
OF RESISTING extremes OF eli nate HaeD their
wood Is sOIdiied, cT, ao Ii Is properly termed
tL0rCGSaly Tpened; We also know maj the same
plant growing In dry climate, or la 4 DIS s1tl,
or IL situation thoroughly drained from Va n
Outing winter, VIII resist much more cold ta4u
III cultivated 10 d damp climate or In wet soil
or 10 u place affected by water In w,nter
whatever teGdS TO render the tissue OF nlants
moist. OF In any degree sueculent. viii increase
ats power OF conducting heat and consequently
augment the susceptibility or growtns to Inc
II Huence or frost, and on the other hand
Whatever tends 10 diminish their humidity, Will
al the same time diminish the conducting
po"ef OF Tue Tissue. ana with /, the suSceptL
Diiity TO injury.
Thus We cab account for the destruction OF
plants Dy most Independently OF ne injury which
would result from The inecn anlcal eXoansion or
tne sap. bursting or cells ana destruction Of
TISSUE; ana the greater susceptibility to cold tn
spring may be partly aScIfbed 10 The plants con-
RAINING more aqueous matter In theft structure
al That period thau they contain during win
Ter, as well as from the Ordinary causes OF che
greater aridlty OF tue air which occasionally
obtains during the months OF March ant April.
III Is A PREVALENT FALLACY
10 suppose that corresponding degree OF latt-
'"io VIII nave corresponding climate in all
parts OF the world, or that a plant Will grow
equally well Ia al countries that have similar
minimum tnermofneIrfcai temperature to that
or which &c Is native. There are other I'm
polant factors besides that OF the heat degree
IN cue atmosphere, Which Influence che condi-
Tons favorable 70 plant growth such as the rain
iali, sunlight, the Typographical features of
The country, and, most d. dsige OF all the nv
s1omctrlcai condition OF the air
AS FAMILIAR example. We may aliuie TO the
AUSTRALIAN VeGetatiOn-the acaciaS eucalyptt
DO1OAldS, caSuar119s, 6c.,-Whirl fl their native
haDitatS endure as much az Is degrees and "a
Occasionally noted. - degrees OF frost but
which, when grown IN this locality, are mostly
destroyed when the thermometer reaches 70 the
freezing point Ia this case We have evidence
pf the influence which
DRY AND HIGH sUIYsR TEMPERATURES
exercises upon the c0ld-reSlsting powers Of
plants IL IS well Known that the Australian
Climate Is at times exceedingly arid, with
nigh degree OF heat which so thoroughly rtpeus
and hardenS the annual growths thai the
young shoots become quite brittle under It's IN
naehce, and vegetation IS thus fortified against
cold. - ' ~
, me temperature and physical condition OF
tne soI. nave also al important controlling iu-
4uehCe IN the old-reSiSting power OF plants
n!eSs proper degree OF moisture is furnished