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ACCLIMATION OF PLANTS.
In the discussion of this topic, I have started out with an unusual number
of quotations from eminent scientists and horticulturists. As I proceed, you

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will notice that the word denoting the subject under consideration is spelled
or pronounced in several different ways.

AN ADVERSE OPINION.
Several of the first quotations are from an editorial in the Gardeners' Chronicle, page 492, October, 1875. He writes: "Incorrect terms are a great
hindrance to the progress of natural science, because they not only convey
false ideas but imply their acceptance as acknowledged truths. Now, if ever a
word was unluckily chosen to express a fact or process, actual, possible, or only
wished for, it is the word ACCLIMATIZATION. And the worst of it is, that it
is now too late to make a change. Twenty or thirty years ago the world's expectations in this matter were probably more sanguine than they are at present;
for endeavors made have not been crowned with the success anticipated."
The author mentions begonias and some other plants as cases in which horticultural art has not been able to effect the slightest change in their constitutions
in that respect, -they remain exactly what they were from the first. These
plants were propagated by cuttings or lavers. He adds, " What have the acclimators acclimated?" May we not venture to reply, 'Nothing whatever;'
because, as we believe, the hardiness found to exist in plants and animals after
their introduction to this and other countries, was already innate and inherent
in them before they left their native shores. Their change of home has sim-
ply tested their robustness, but has not altered their constitution. Acclimatization has failed (in Britain) to make Bobbett's corn the staff of life; it has
not made New Zealand flax grow as luxuriantly out of doors here as in New Zealand; it has not even acclimated the potato. With this experience of facts,
may we not be permitted to doubt whether the process which we understand
by acclimatization really and practically exists at all? Strange plants and
animals introduced into countries, new to them, have immediately shown
their fitness for the soil and climate and have multiplied and spread to such
an extent as to become naturalized." Of this class of plants I may mention
most of our weeds, nearly all of which are imported. In Australia, New Zealand, and many parts of South America, some of the introduced plants thrive
better than the native plants and are fast crowding them out. The editorial

"What may be effected by natural causes, in the course of millions of years, we
cannot tell, what is done in the way of acclimatization by human agency during
one or several human lifetimes, appears often to be infinitesimal and quite inappreciable. The original nature of plants is little changed by art. Much that
has been written, and more of what is believed concerning acclimatization, is
sheer fallacy. But little of actual fact can be sifted out of the masses of chaff
to prove that any plant is one whit hardier than it was when first imported."

OTHER OPINIONS.
The late Mr. McNab of Scotland, was an eminent botanist and lived a long
life as a most successful gardener. In 1874, in his opening address before the
Botanical Society of Edinburgh, he says: "I am one of those skeptical individuals who do not believe in it [acclimatization], and still maintain the
opinion that a plant is as hardy when first introduced into this country as it is
after being half a century in cultivation." He gives numerous examples " to
show that certain plants, although long grown in a conservatory and planted
out will thrive during a series of good seasons, but will succumb after an
adverse summer followed by a severe winter."

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Dr. John Lindley, in Morton's Cyclopedia of Agriculture, writes, "That
cases in support of this view are not numerous, however plausible the theory
may be, and it may be doubted whether in fact any one example of acclimatization, in any considerable degree, if at all, can be produced."

The editor of the London Horticultural Magazine writes: "We deny that
a seedling can be rendered more hardy than the parents; although we do
admit that seedlings may be more hardy than their parents." Cases of some
seedling dahlias and potatoes are cited as examples; that is, some of the
seedlings will endure more frost than others." He adds: "The question of
acclimatizing plants, therefore, is only tenable if we put another construction
on the word, and instead of using it as meaning the making a plant more
hardy than it naturally is, use it in the sense of proving how hardy a plant
naturally is, for such is all we can do."

THE TERM DEFINED.
"A. R. W," probably A. R. Wallace, in the Encyclopedia Britannica, says:
"Acclimation is the process of adaptation by which animals and plants are
gradually rendered capable of surviving and flourishing in countries remote
from their original habitats, or under meteorological conditions different from
those which they have usually to endure, and which are at first injurious to
them. The subject is very little understood, and some writers have even
denied that it can ever take place. It is often confounded with domestication
or with naturalization. Perhaps in most cases of naturalization there is no
evidence of a gradual adaptation to new conditions which were first injurious,
and this is essential to the idea of acclimation." The author goes on to say
that "It is evident that acclimation may occur (if it occurs at all) in two
ways, either by modifying the constitution of the individual submitted to the
new conditions, or by the production of offspring which may be better adapted
to those conditions than their parents. The alteration of the constitution of
individuals is not easy to detect. Habit has little (though it appears to have
some) definite effect in adapting the constitution of animals to a new climate;
but it has a decided, though still slight, influence in plants, when, by the process of propagation by buds, shoots, or grafts, the individual can be kept
under its influence for long periods. In most cases, habit, however prolonged,
appears to have little effect on the constitution of the individual, and the past
has no doubt led to the opinion that acclimatization is impossible."

TESTIMONY OF PROF. DARWIN.
I next make some extracts from the writings of Charles Darwin. He calls
it "the much disputed subject of acclimation," and says: "The attempt to
acclimate either animals or plants has been called a vain chimera. No doubt
the attempt in most cases deserves to be thus called, if made independently of
the production of new varieties endowed with a different constitution. Habit,
however much prolonged, rarely produces any effect on a plant propagated by
buds; it apparently acts only through successive seminal generations." On
the whole, he concludes that "habit does something towards acclimation,"
even where the plants are propagated by budding, layers or cuttings. As an
illustration he mentions that vines taken to the West Indies from Madeira
have been found to succeed better than those taken directly from France.
This is the only example I can find.

Darwin and Wallace, and the editor of Nature use the term acclimatization
in a broader sense than it is used by editors of the Gardeners' Chronicle, the

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editor of the Garden, the editor of the London Horticultural Magazine, Dr.
John Lindley, or Dr. McNab, of Scotland. The former set of authors believe that it is a legitimate part of acclimatization to produce new hardy varieties, races, or hybrids from seeds.

EXAMPLES OF ACCLIMATION.
In this broad sense, every one must certainly believe that most plants, if not
all can be acclimated in a climate more or less uncongenial to them. One of
the most remarkable cases of this kind is Indian corn. All of our races of
corn have evidently been derived from one species. We have numerous varieties of pop corn, sweet corn and field corn; corn with long, pointed kernels,
or with round kernels, or indented kernels. We have kernels which are
hard or soft, red, yellow, white, violet, black or striped. We have ears with
eight rows of corn, and from this up to thirty or more. We have ears of corn
varying in length from one inch to fifteen or sixteen inches, and stalks varying in height from twenty inches to sixteen or more feet. We have in the United States corn which will ripen in ninety days, and other varieties which require in the warmer sections six or seven months to mature.

The cabbage (brassica oleracea) also varies much, and has produced all sorts
of cabbage, early and late, all sorts of cauliflower, broccoli, kohlrabi, etc. The
list of grains, vegetables and flowers might be indefinitely extended. The
examples of a difference in the hardiness of seedlings of trees is also familiar
to all of us. The Baldwin and Large Yellow Bough are tender in many portions of Michigan, where the Red Astrachan and Ben Davis are hardy.
Examples might be given of a difference in the hardiness of pears, plums,
cherries, peaches, grapes, blackberries and other fruits. The same thing was
long ago noticed in the hardiness of seedling oranges in Italy. The previous
example and the next example are taken from Darwin's "Animals and Plants
under Domestication,” to which all are directed if they wish for further illustrations.
Mr. Grigor states that seedlings of the Scotch fir (Pinus Sylvestris), raised
from seed from the Continent and from the forests of Scotland, differ much.
The difference is perceptible in one-year-old, and more so in two-year-old
seedlings. Closely similar facts have been observed with seedling birches.
Pomologists of Iowa and Minnesota are raising seedling fruits some of which
are hardier than the parent plants.

AN OPEN QUESTION.
In striving to obtain seedlings better adapted to any peculiarity of climate,
I cannot find that any experiments have been made to decide the following
point: Shall we plant seeds raised in a more congenial climate, or shall we
be more likely to gain the point desired by planting seeds raised in the climate
for which we want suitable trees or shrubs? I should expect the results would
be more favorable by planting seeds grown in the same locality, or, still better,
in one with a similar climate a little distance away, provided the seeds were
from tolerably well-grown and healthy specimens of fruit.

Before closing, I will briefly refer to the matter of attempting to acclimate
specimens of trees or plants. For example, we often hear people speak of
acclimating a certain individual young evergreen tree. As we have seen, there
is probably no such thing as acclimating a single tree or plant. We can plant
it in the most favorable spot at our command. The soil should be of suitable
texture and well drained. The cultivation should be such that the tree may



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grow at a moderate rate and mature well. A young tree generally grows faster
than an old one. It is more likely to be injured by extremes of heat, cold,
drought or moisture than a tree which has become established and has arrived
at the prime of life. We may shelter or otherwise protect a tree while it is
young, and thus carry it through the most precarious part of its life. This is
almost always done with seedling evergreens. When well established they may
be allowed to take care of themselves. This early nursing of trees is not
acclimation.

President Lyon .- Whether technically there is any such thing as acclimatizing plants, the fact is pretty well understood that plants become adapted to
certain climatic conditions by following certain methods of caring for them.
There is another matter connected with this subject that is worthy our attention. It is the selection of seed to produce the best plants. The thought has
come to me from certain experiments performed by Mr. Downer and Mr.
Hathaway in the production of new varieties of strawberries. Mr. Hathaway,
I think took fully as much pains with his work as Mr. Downer and still the
latter brought out several fine seedlings, while Mr. Hathaway brought out but
one of value. My impression is that the difference lies mainly in climate; the
seasons of Kentucky are more favorable to the perfecting of the species than
those of Michigan; and it occurs to me that this is worth our consideration
in developing any sorts of plants by means of seed. We should seek such a
climate if possible as is the best adapted to the plant. A corollary to this
might perhaps be added that is already taken advantage of by foreign
seed growers-plants set apart for seed growing with the view of developing a
better strain should at the time of seeding be subjected to the most favorable
circumstances and conditions. A common example of climate affecting
seed, is that of Indian corn; in the north it gradually deteriorates, while farther south where it is naturally adapted we may look for the best opportunities
of perfecting the seed. If the germ of vigor is in the germ of the seed it is
important that we make that seed as healthy and vigorous as possible.