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Pests of Hardy
Ferns. |
There are around 12,000 species of ferns, and they include some of the most
popular of all nursery plants. They are found throughout the earth. In the
United States they are usually found in woodlands, meadows, and along roads or
stream banks. Generally they are in moist areas but can also be found in direct
sunlight. They have roots, stems, and leaves of all vascular plants. Fern leaves
are called fronds. Except for tropical tree ferns (to 80 feet high), the
majority are close to the ground, but extrodinary diversity exists on the basic
plan, and yet they have so many common characteristics they can be logically
discussed as a single group.
In other words, although thier roots grow into
the rooting vegetation that collects in the crevices of trees, they do not draw
food from the trees upon which they are physically supported. But ferns can also
be terrestrial. The terestrial kinds thrive in the shady, humid atmosphere at
the base of trees, or anywhere else at ground level where there is an adequate
supply of leafmold-enriched soil for thier roots. Both epiphytic and terestrial ferns need high humidity to
keep thier fronds firm.
The fronds and feeding roots of most kinds of fern grow from
rhizomes, which are fleshy stems that generally serve as storage organs.
Rhizomes usually grow horizontally underground, but those ferns of the genera Pyllitis and Polystichum, for instance, are stemlike, short, and
branching. Rhizomes of other ferns can creep or cling aboveground, or they can
extend horizontally underground, as in the adianthums. Fern rhizomes are always alike, though, in
that they are coated, to a greater or lesser degree, in a furry, scaly covering
that is black, brown, or silvery white.
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Light/
Ferns. |
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Watering
Ferns. |
The quantity of roots growing from rhizomes depends largely
on the form of the rhizome itself. For example, the underground rhizome of a
terrestrial fern is certain to have a much denser root system than that of an
epiphytic plant. In all types of fern though, the roots tend to be thin and
wiry.
The fronds, which are a combination of stalk and leaflike
blade, vary enormously in size and shape. Frond size can range in length from a
few inches to many feet, and in width from an inch to as much as 3 feet or
better. Frond stalks are virtually absent in plants of some genera (for instance
Platycerium... Stag Horn), whereas in others, such as the polypodiums, they account for more than half the total
length of the frond.
Since ferns are non-flowering plants, it follows that they
do not produce seed for propagation. Instead, ferns reproduce themselves by
means of spores, wich are carried by the millions on
some-not-all-fronds.
Certain ferns reproduce not only by means of spores but also by growing baby ferns on thier fronds.
These are generally known as bulbils, although thay are not technically bulbs,
and these can be easilly detatched and used for propagation.
