cultivated vegetables, in the proper statistics of the farm, which
might otherwise find a place in the Botanical Report.
OF THE USELESS PLANTS.
A large number of the plants which are considered useless,
because they have yet no known application, are particularly
described in this Report. They occupy space ; they aid in covering
the earth with vegetable life. They are, indeed, weeds,
and often considered as mere nuisances. What is the advantage
derived from them ? What object is designed by them ? Can
any one be in truth useless ? Certainly not, is the reply to the
last question. The others may receive the following answers:
1. The vegetable kingdom is the great means of purifying the
atmosphere, so that it may sustain the animal kingdom. Respiration
of animals, and various operations in nature, produce such a
change as tends to make the atmosphere unfit for its great office.
Its oxygen has become combined with carbon, or the essence of
charcoal, and cannot be separated by the lungs so as to support
life. This separation is effected by vegetables. They take up
the carbon and restore the oxygen to the atmosphere. They do
this as they grow in the air, and also as they grow in and under
water. Provision is made for the absorption of carbonic acid by
water, and thus food is supplied to plants, and life to animals.
This is one of the most beautiful provisions in the economy of
Divine Providence. It has sometimes been doubted whether
vegetables .were able completely to accomplish the object. None
have maintained, however, that they did not operate largely and
chiefly to this end. Even the general opinion seems to be strongly
in favor of their perfectly effecting this purpose. To accomplish
this object, vegetables must be spread widely over the
earth. It might not be sufficient to depend upon the results of
cultivation. Besides, the vegetables must be formed for growth
through all the warm season of the year, and in all the variety of
soil, situation, climate, condition. Plants that are directly useful,
would not be more likely to effect this end in all this variety ; it
is doubtful, indeed, whether the useful plants would be so well
adapted to this state of things, as they generally require a more
favorable combination of circumstances.
To secure this end, too, it is important that a host of plants
should have no natural attractions for animals, that they may grow
without molestation, and exert their influence upon the atmosphere
without interruption.
This end is secured by the foliage of forests, which is chiefly
removed from all access of destructive agencies.
It is a general fact, that animals multiply nearly in proportion to
the supply of food. If all vegetables were food for animals, the
entire action of a great multitude could not be employed, as it
now is, in purifying the atmosphere.
In this grand respect, all plants are performing a work of the
highest utility. Unseen and silent, they renovate the very pabulum
of life.
2. Another end of the vegetable kingdom is food for the animal.
All animal life is ultimately supported from the vegetable
world. But animal life abounds ; tens of thousands of smaller
animals, and especially of the insect tribe, must be dependent, as
well as the larger animals and man, upon vegetables. By their
foliage and seeds, the plants now considered as useless by many,
may give far more support in the article of food, than is commonly
imagined. We know that many small birds derive much
food from seeds, as also a host of insects ; and yet we may be in
relative ignorance on this subject. Even the animals of the seas
must have no inconsiderable dependence upon vegetable substances
for their support. A great amount of decomposed vegetables must
be annually poured into the great reservoir by all the rivers.
3. Plants enrich the soil, and fit it for the production of vegetables
in greater quantity. This is true of vegetables generally,
when they live and die and decay on their place of growth. Cultivation
often exhausts land, because no adequate return is made
for the vegetable matter removed from the fields. The vegetables,
often considered useless, will, by their decay, perform
another important service, in enriching the earth, and improving the
soil. It has long been remarked, that this effect follows, because
2