Fabulous Ferns

Originating around 360 million years ago, ferns still populate the earth. They are vascular plants but are herbaceous, or lacking wood. This means they have both xylem (which carries water and nutrients) and phloem (which carries mainly sucrose). There are around 10,000 species of ferns in the world.

Ferns also reproduce through the use of spores. Spores often contain lipids, proteins and calories, tempting some animals to eat and spread them. Spores are contained in packets called sori (plural of sorus).

Most ferns have fronds, further divided into the stipe, or “stem,” which leads up to the blade, containing the pinna coming out of the rachis. Pinnules, which look like tiny leaves, come out of the pinna rachis. Groups of pinnules form the pinnae. The fronds are connected by root-like parts known as rhizomes and are grounded by roots.

Ferns can be found in woodlands, on mountains, deserts and open fields.

Many ferns rely on mycorrhiza. Mycorrhiza is the relationship between fungus and many plants. Certain types of fungus grow around the roots of fungus, either intermingling its cells with those of the root or not. The fungus takes sucrose and glucose created in the fronds of the fern through the roots. In return, the mycelium (like a plant’s roots) of the fungus has a larger surface area than the plants roots and therefore can make it easier for the plant to absorb water and nutrients. Furthermore, many plants lack the capability to gain phosphate ions from basic soils where phosphate is demineralized. Fungus, however, can take in these ions for the plant. This is quite a fascinating connection between fungi and plants in which both partners benefit like that between bees and flowers or birds and fruiting plants.

Here are some common ferns in Georgia:

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Southern Lady Fern

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Underside of a Marginal Wood Fern frond showing sori

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Christmas Fern

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Resurrection Ferns growing on a Sand Live Oak

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Marginal Wood Fern

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Northern Maidenhair Fern

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