32 
usual shelter from long east winds, have passed 
through even those very severe winters, so well 
remembered, in which this island proportionally 
participated.” * * * “J believe,” the Doctor 
adds, “ that in a great many matters appertain- 
ing to vegetation, whether in horticulture or agri- 
culture, the question of light is often of much 
more importance than that of heat, however 
much it has been overlooked by agricultural as 
well as philosophical writers. It is of most mate- 
rial importance as to the perfection of flowers, 
whether in vigour, colour, or odour; and not less 
So, as is very well known, as to the ripening of 
fruits. Nor does it appear to me less so as to 
ordinary agriculture, whether as it relates to the 
_ perfection of certain herbaceous plants, or the 
ripening of grain. I think this is peculiarly visi- 
| ble in certain parts of Scotland, where the most 
serious differences in this respect occur ; where 
no other circumstance of difference than that of 
the annual quantity of light can be discovered, 
and when indeed the condition as to temperature, 
and soil both, is highly in favour of those climates 
where the produce is worst. This is remarkably 
true in comparing the eastern and western sides 
of Scotland generally, and in noting the singular 
limitation of the region of wheat thus produced ; 
| and, unless I mistake, a difference in the vigour, 
and especially in the vigour of flowering, in clo- 
ver, not to be accounted for by differences in the 
soil, method of cultivation, or quantity of manure. 
And while the power of producing wheat, or what, 
for the present purpose, is analogous in principle, 
the early ripening, as well as the superior quality 
of barley, diminishes in proceeding westward on 
a parallel of latitude, till we arrive at the cloudy 
region, it reappears on passing this again to the 
westward ; insomuch, indeed, that much more 
northern latitudes, if the lands are insular and 
flat, are superior in these respects to the south- 
ern ones, while there are no differences as to soil, 
cultivation, or aught else, capable of explaining 
the facts.” 
Plants, in general, bear to be removed from 
cold to heat better than from heat to cold; and, 
therefore, a greater proportion of the plants of 
this country thrive in the south of Europe, than 
of the plants of the south of Europe will thrive 
in this country. Yet the reverse of the general 
rule, in both of its applications, may frequently 
be observed. ‘The removal of some of our plants 
to considerably warmer climates than our own, 
is often a task of much inconvenience and diffi- 
culty ; and the successful removal of a few others 
is an utter impossibility. Wheat and barley, for 
example, will not grow within the tropics ; and 
several of both our shrubby and our succulent 
plants would soon wither to extinction in any re- 
gion of much heat anddrought. Many plants of 
hot countries, on the other hand, readily accom- 
modate themselves to our climate, either by means 
of the protection they obtain during winter from 
snow, or with the help of the warmth and shelter 
ACCLIMATATION OF PLANTS. 
afforded by our shrubberies and_ plantations. 
“ Every one, on entering a wood in winter, must 
have been struck with the difference of the tem- 
perature from that of the open field, as well as 
seeing there several plants, such as the cowslip, 
violet, and snowdrop in full flower ; while, in the 
neighbouring gardens, their leaves have scarce | 
made their appearance. It is well known that 
many rare plants, which had disappeared with 
the cutting down ofa wood, have reappeared when 
it has again grown up. ‘ One reason why the 
American plants grow so luxuriously at Fonthill 
Abbey,’ says a writer in the Gardener’s Magazine, 
‘is, that they were introduced among native un- 
derwood, interspersed among bushes of hazel, 
dogwood, &c., and sheltered by firs, oaks, and 
other timber trees,’ A shrubbery is therefore to 
be considered as the best place for acclimating 
exotics, whether trees or herbs, and more espe- 
cially if the soil be dry, and the shrubs chiefly 
deciduous ; for it should not be forgotten that. 
many believe that a coppicewood of evergreens is 
always colder than one of deciduous bushes, owing 
to the leaves presenting a greater surface for eva- 
poration. Groves of evergreen trees, on the other 
hand, especially of the pine and fir tribe, present 
a warmer climate beneath them than groves of 
deciduous trees; because the former, from the 
closer texture of their exterior surface, reflect 
back more completely the heat radiated from the 
ground below. The more any plant is shaded in 
winter, the less danger it will be in of suffering 
from frost. For, when a plant or water is so 
situated as to be overtopped by trees, the radia- 
tion of caloric is ina great measure checked ; and 
thus, in such situations, we may often observe 
water unfrozen, and plants unhurt by the cold, 
and many retaining their leaves, when others of 
the same species, at a short distance, but un- 
shaded, lose their leaves, and suffer considerably.” 
—| Paper of J. 8. Bushnan, Esq., in Quar. Journal 
of Agriculture.| Yet constant shade in summer 
might, in many instances, far more than counter- 
work all the advantages of constant shelter in 
winter ; and the want of a free soiland a suitable 
ventilation during winter itself, may, in some 
cases, be ill compensated by mere protection from 
some degrees of cold. The shelter of woods and 
shrubberies as a means of acclimatation, there- 
fore, must be understood to have decidedly re- 
stricted limits, and ought to be employed only in 
the case of plants which naturally grow on poor 
soils, and receive little damage from the dropping 
and the shade of trees. 
Mr. Bushnan, immediately after the passage 
which we have quoted, says, “ Mr. John Strut, 
the gardener at Beil, who has succeeded in ac- 
climating numerous plants, states, in the Trans- 
actions of the London Horticultural Society, that 
he has found poor, dry, and shallow soils and 
declivities to be best adapted for preserving plants 
through the winter season. The quicker the su- 
perabundant fluid passes away from the roots the 
