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The main idea of this book is not to give detailed
technical descriptions of the flowers of the Highlands, but to describe
each one in easy language so that you, my readers, will have little
difficulty in recognizing the commoner species.
My object is to describe each plant in relation to its
environment and the conditions of life it has to face, with special
reference to its adaptations to combat these conditions. I shall also
describe the beautiful places these plants inhabit with descriptions of
some of the loveliest spots in the Highlands. I shall also show you how
flowers are amazingly constructed with regard to insect visitors and
fertilization.
I want you to regard wild flowers not just as museum
exhibits, as lists of difficult Latin names, or as splashes of colour upon
the masterpieces of Nature. No, I wish you to regard them as sentient
beings with hopes and fears and ambitions much like our own. Their
beauty, their colour, their perfume and their form are not just there to
adorn the fields and mountain sides or to delight the eye. They are part
of the personality of the flower and are all adapted to their insect
visitors and pollination.
For example, the honeysuckle has pale almost white
flowers and a beautiful perfume in the evening time, solely for the
purpose of making itself conspicuous by night to its benefactors, the
nocturnal sphinx moths. As we study this book, we shall meet many
examples which show that colour and perfume are but devices for making
flowers conspicuous to their insect visitors.
No woman ever took more trouble over her complexion,
her dress and her deportment to attract the man she loved than the flower
has taken to attract its particular benefactors. The bright hued petals,
whose every line and vein have their significance, the beautiful perfume
and the sweet nectar hidden where its benefactor alone can find it, are
utilized with just as much success as the cosmetics and perfumes of my
lady.
Verily the Great Master said truly the lilies of the
field that ‘Solomon in all his glory was not arrayed like one of these’.
Yes, for where in all the world, whether among the works of Nature or of
man, can one find such exquisite beauty, such wealth of colour and
perfume, and such a subtle mixture of loveliness and freshness as we find
among flowers?
We may ask why it is that the insect knows that a
certain flower has hidden its nectar for its benefit?
For this reason. Insects existed long before flowering
plants were evolved. Certain types, however, were probably dependent on
existing plant forms such as club-mosses, ferns, etc. for life, so that a
relationship already existed between the Insect and Plant worlds. But as
plant forms evolved, types akin to pines developed, which produced pollen
and were dependent of the wind for pollination. Certain insects gradually
took to pollen as a food for themselves and their larvae instead of spores
of Ferns and Club-Mosses. They included primitive bees, beetles, etc.
In the course of evolution, flowers produced the
pollen-bearing stamens and the receptive stigma in the same flower, and
they found that insects visiting flowers for pollen pollenized the flowers
in their visits much more surely than the wind could do. So the commenced
to produce coloured petals and then perfumes to attract insects. Other
types produced nectar in special glands, and certain insects, especially
bees, visited the flowers for this nectar, mixing it with pollen to form
food for their young.
As flowers became more and more adapted to their insect
visitors, so did the insects become more and more adapted to the flowers
they visited.
Flowers, finding that many insects visited them solely
for nectar and transferred no pollen in return, began to hide the
nectarines in spurs and tubes where only certain insects could reach it.
The first primitive bees were short-tongued, but
gradually developed longer tongues in order to reach the concealed
nectarines. Today long-tongued bumble-bees are the only insects that can
drain the long spurs of such plants as the linaria, the delphinium and the
columbine, whilst these flowers are absolutely dependent on the bumble-bee
for fertilization.
Certain insects also favored certain colours more than
others. Bumble-bees were more attracted by blue than by any other colour
and hence flowers such as delphinium which are specially adapted to
bumble-bees flaunt their favourite colour, blue. At the same time,
certain flowers, especially white flowers, which were not in themselves
very conspicuous, developed sweet smelling perfumes to attract their
visitors.
Other plants, such as the Umbellifers, catered for the
mob such as flies, beetles and other short-tongued insects. They took no
trouble to conceal their nectar, producing it where it would be easily
obtainable, flaunted white petals, and if perfumed, were rather strongly
smelling.
Thus, throughout the flower world, we find that each
species is adapted by colour, by perfume and by shape to certain insects
or types of insects and that in many cases they are entirely dependent on
their visitors for the production of the species.
We shall meet with plants, however, whose flowers are
small and inconspicuous. Most of these depend on self-fertilization for
reproduction.
We may ask why it is that, if these flowers can set
seed year after year by self-fertilization, others have taken such pains
to make it impossible, for self-fertilization is a much surer process than
pollination by insects.
But here we meet one of the great marvels of the flower
world. Darwin proved that if we took equal quantities of self-fertilized
and cross-fertilized seed, a much greater percentage of cross-fertilized
seed is fertile, and what is more it gives rise to a hardier and tougher
stock.
Hence every plant is trying to attain the goal where
all its seed must be cross-fertilized. The devices to make sure of this
are very numerous and we shall meet with many interesting types in the
following chapters.
We shall also meet with types still dependent on the
wind for pollination. Willows, pines, crowberries, etc. They all possess
inconspicuous flowers and are less interesting than the other flowers.
Having discussed the adaptation and evolution of
flowers with regard to their insect visitors, we must discuss the
evolution and adaptation of plants to combat climatic conditions and
environment.
All plant are faced with a hard struggle against cold
and damp, heat and drought, animal enemies, conditions of environment
(soil, altitude, etc.) and the competition of other species.
Throughout long ages plants have gradually adapted
themselves to the climatic conditions of their particular stations. Thus,
for example, plants that inhabit hot, arid situations have evolved thick
water-conserving tissues, hairy coasts, thorns and spines in order to
live. Those of the high mountains have a dwarf stature and a specialized
architecture which enables them to combat Arctic conditions.
Thus we see that the form of the leaves and the build
of a plant are largely due to climatic conditions.
To fight against the attacks of animals and insects
many plants, such as the Ranunculus, have produced acrid juices which make
them unpalatable, or again, they are armed with sharp prickly leaves as in
the Holly, or with thorns as in the Hawthorn. Thus have natural enemies
aided in the evolution of plant forms.
Again plants must always struggle against the
competition of their own species and of other species. The first is
combated by winged seeds which distribute the seeds far from the parent
plant, or by light seeds which will be blown a considerable distance from
the parent plant. Against the competition of other species some plants
possess a rosett of leaves when young, which prevents other plants
encroaching too close, or they send out runners which can take advantage
of available space, or they may form close compact colonies which keep out
other competitors.
Again plants growing in forest land are adapted to
withstand the shade of trees and to climb over them to flower in the
sunlight above.
These few examples show us in what a marvellous fashion
plants have evolved because of the struggle for existence.
This adaptation to environment has resulted in plant
associations. In a plant association we find different species of plants
which are able to live together under the same conditions of environment,
climate, competition, etc.
Thus in the pine wood association we find that the
pines, whort berries, junipers, heaths, pyrolas, linnaea, Goodyera, etc.,
all live together to the exclusion of other species because they are
specially adapted conditions prevailing in a pine wood.
It is my intention in this book to describe the various
association of plants to be found in the Highlands.
We shall commence with the interesting association of
Alpine plants which includes those plants specially adapted to the
withstand conditions of high altitudes. >From there we will descend to
the association of the mountain pastures, followed by the moorlands and
bogs, the pine forests, the mixed woods, the loch and their fringes, the
marshlands, and lastly the meadows and pastures.
These groups contain many highly interesting plants,
the study of which will give us a good insight into the marvels of the
flower world. |
