Fabulous Ferns

In the forest, clumps of sword ferns with green, arching fronds seem to leap up from the forest floor. As the fall leaves scatter to the ground, it is heartening to know that the ferns will stay green all winter. In the spring, the new fronds, coiled up as fiddleheads, unfurl in bright new shades of lime-green. The old fronds gradually decay back to the earth, making a rich layer of humus.

Ferns love our moist climate, and there is a great variety and abundance to discover in our area. Ferns are intermediate between simple plants like mosses, and more highly evolved flowering plants. Like flowering plants, ferns are vascular plants, and have specialized tissues for conducting food and water. Like mosses and more primitive plants, ferns reproduce by spores rather than seeds. Ferns are very successful and ancient plants. A few hundred million years ago, steamy tropical forests were full of ferns, some as large as trees. Ferns and other ancient plants make up today’s coal beds.

Like many things in nature, fern reproduction is complex. When a spore germinates, it develops into a tiny heart-shaped gametophyte. The gametophyte produces the sperm and eggs in specialized structures called antheridia (male) and archegonia (female). Water is needed for fertilization, which occurs when the sperm swim over to the eggs. After fertilization, the plant begins its sporophyte phase, growing into a leafy green plant that will produce and release spores. The two phases of the fern’s lifecycle, the gametophyte and the sporophyte, are known as the “alternation of generations”.

Ferns have scaly, horizontal underground stems called rhizomes. The fronds sprout from the rhizome, as do the fibrous roots. Each frond has a stem (stipe) and a leafy green blade, made up multiple leaflets or pinnae. Many of our common ferns have neat rows of round sori, or spore sacs, on the underside of the leaves. Sometimes, a protective cap (indusium) covers the sori. Spores are only released when conditions are right.

Some ferns have specialized fronds that produce spores, and these look very different from regular fronds. Spore producing fronds usually arise from the center of the plant. Moonwort, a small and beautiful fern much sought after by botanists, produces sori that look like miniature clusters of grapes. Deer fern, a fern of wet forests and stream banks, has distinctive spore-bearing fronds with leaf margins that roll inwards to protect the sori.

Ferns can be found in a surprising variety of habitats, including woodlands, rocky outcrops and stream banks. The most common fern locally is the sword fern. The individual leaves of this large, clumped evergreen fern are sharp-toothed. At the base of each leaf is a small forward-pointing lobe.

Two other common woodland ferns, lady fern and spiny wood fern, have softer foliage that dies away in the winter months. Lady fern has diamond-shaped fronds that are narrow at the base and tip and widest at the midpoint. Spiny wood fern has triangle-shaped fronds.

The individual fronds of licorice ferns often adorn the mossy trunks of maple trees. Licorice fern has a licorice-flavoured rhizome. Licorice fern may also be found growing on the ground, or over fallen logs.

One of the most beautiful ferns is the maidenhair fern. Maidenhair fern has black stems, and delicate fan-shaped foliage, and can be found along stream banks and cliffs.

Bracken is a large fern that establishes itself on disturbed ground and sandy soils. Bracken has branching fronds and a smooth, somewhat rigid stem. Bracken is well adapted to forest fires. After a fire, new growth sprouts from the underground rhizomes.

Dry rocky outcrops might seem like unlikely places for ferns, but many ferns find small pockets of moisture between the rocks. Small and intricate, parsley fern, fragile fern, holly fern, spleenwort and Indian dream fern are just a few of the species to eke out a living between the rocks.

First nations peoples have used ferns medicinally for thousands of years. They were also used as layering in pit cooking and to separate stored foods, as well as for flooring, bedding and basketry.

In some areas, ferns are important winter forage for deer and elk. Ferns also provide under story protection for numerous birds and small mammals.

Native ferns, sword ferns in particular, make great low maintenance garden plants. They can be purchased at local nurseries, or salvaged from areas that are about to be developed.

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