Bracken Fern

Pteridium aquilinum

Markku Savela

Bracken is a large fern, sometimes growing over three feet tall. Instead of the usual leaves, ferns have fronds, made up of smaller leaflets (groups of mini-leaves) with small pinnae (tiny mini-leaves) on them.

Bracken fronds are shaped like triangles. Each frond usually has three leaflets.

Bracken grow in large colonies in fields, brushy areas, and woods. They have thick root-like stems, called rhizomes, underground. Rhizomes can grow six feet long, and many fronds may grow from one rhizome. Each rhizome also has tiny, hair-like, black roots on it.

Each winter, Bracken's fronds die with the frost and fall to the ground. New fronds will grow the following Spring.

Bracken Ferns can reproduce two ways. One is by rhizomes spreading, and the other is by spores. Ferns do not have flowers like most plants. Instead, on the underside of the fronds, there are small objects, called sori. The sori produce spores, which are a lot like seeds from a flowering plant.

Spores travel by wind and grow new ferns in new places.

Bracken Ferns often grow under oaks, pines, hickories, maples, and beech trees. They are frequently seen growing with violets, oak fern, bunchberry, asters, sarsparilla, and other plants.

Bracken Ferns help some plants grow, and hurt others. They are allelopathic to some plants, which means they let out chemicals that keep them from growing. Black Cherry trees are one plant that has trouble growing around Bracken Ferns.

Other plants are helped by Bracken. Because Bracken Ferns grown in thick colonies, they can hide small tree seedlings and other plants that might be eaten by animals.

Young Bracken Ferns are eaten in the Spring by White-tailed Deer. Rabbits will also eat fronds. Many animals and insects won't eat Bracken because of chemicals in it that make them sick. There are several species of insects, including sawflies and some caterpillars, which eat Bracken. Many of these caterpillars were introduced from Europe.

Sometimes a liquid, much like nectar in flowering plants, collects at the bottom of pinnae. Ants and other insects will drink from this. Ants will also protect the ferns by attacking insects which eat Bracken.

There are some micorrhizal fungi (Fungi which help plants) which share nutrients with Bracken. Bracken Ferns also help other plants by taking phosporus and other nutrients from the soil and changing them so that plants can use them.

Bracken Fern is great cover for small animals, such as insects, spiders, and salamanders. Old fronds bend and cover the forest floor or meadow, hiding these animals from predators.

Thick colonies of tall Bracken can also cover deer, foxes, rabbits, voles, shrews, mice, and birds.

Bracken Fern is one of the first plants (pioneer) to start growing after a fire has damaged an area.

Relationships in Nature:

Animals Using as Food Source

Animals Using as Shelter

Associations With Other Plants


White-tailed Deer

Red-backed Salamander

Black Oak

Black Cherry A

Eastern Cottontail

Wood Frog

White Oak

Black Carpenter Ant Mu

Black Carpenter Ant

Rabid Wolf Spider

Southern Red Oak

Eastern Bloodsucking Conenose

Eastern White Pine

Northern Ringneck Snake

Virginia Pine

Horned Fungus Beetle

Loblolly Pine


Mockernut Hickory


Americn Beech

Garden Centipede

Red Maple

North American Millipede

Silver Maple

Red Fox

Ox-eye Daisy

White-tailed Deer


Least Shrew

Spotted Jewelweed

Meadow Vole

Black-eyed Susan



Eastern Cottontail

Bushy Aster

Goldenrod Spider

Kentucky Bluegrass

Eastern Gray Squirrel

Bigtooth Aspen

Field Cricket

Pipevine Swallowtail

Relationship to Humans:

People sometimes have eaten Bracken Fern, but scientists have discovered that eating too much may cause a type of cancer. Bracken Fern has also been used to make a yellow dye, and it is used to make medicines.


Pteridium aquilinum


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