Common Peatland Plants and Plant Adaptations
Peatland communities support a diversity of plant species that have special adaptations to living in saturated, nutrient poor conditions. Most of the plants found in a peatland system are adapted to growing in saturated soil and peat conditions. The amount of available nutrients helps determine which plants can successfully grow in a peatland community. Plants that grow well in fens, where more nutrients can be found in the upper peat layers, may not be able to grow in the nutrient poor conditions of raised bogs. Plants that grow well in bogs, such as the small-leaved cranberry and Labrador tea, may be found in fens but are not as abundant. Click on the word below or simply scroll down for text and photos.
Sphagnum moss Shrubs Carnivorous plants
Trees Orchids List of Common Peatland Plants
Sphagnum mosses, below, commonly known as peat moss, are particularly good at absorbing water. Some species of Sphagnum moss can hold up to 25 times their dry weight in water. One of the most interesting features of Sphagnum mosses is that the top of the plant grows while the bottom dies and decays, contributing to the accumulation of peat. Sphagnum is one of the more competitive of peatland species - it actually can change the acidity of the environment around it to enhance conditions for more moss to grow. Most Sphagnum mosses can recover rapidly after drying. Most species can tolerate full sun and shaded conditions. The various shades of red color found in several Sphagnum mosses occurs only in open sun conditions.
Most shrubs found in peatlands are adapted to harsh growing conditions. More typical of bogs then fens, these shrubs include small-leaved cranberry, rhodora, Labrador tea, and leatherleaf
. The high-bush blueberry and mountain holly found in fens are much less tolerant of nutrient poor conditions. With firm and tough leaves and woody stems, these plants can tolerate very wet to very dry conditions, wind and ice, and produce a toxin that prevents browsing by mammals. The shrubs that stay evergreen year-round conserve the nutrients they need to support growth and reproduction. Special relationships with root fungi have also evolved to help these woody plants survive in low nutrient conditions. Berry producing shrubs in peatlands provide an important food source for wildlife.
Small-leaved cranberry on a bed of sphagnum moss, left. Leatherleaf in bloom, right.
Labrador tea with flowers about to bloom, and the underside of Labrador tea leaves with distinctive orange 'fur,' which makes identification easy.
High bush blueberry, left, and mountain holly on right, provide food for a variety of wildlife.
Carnivorous plants are among the most unusual of plants. Three types of 'meat'-eating plants are found in Maine peatlands: pitcher plants, sundews, and bladderworts. These plants probably evolved to feed on insects and other small organisms as a supplementary source of nutrients that are in low supply in bogs and nutrient poor fens. Although these plants still photosynthesize, their carnivorous habits allow them to grow more vigorously in a competitive environment.
The
pitcher plant
has
highly specialized leaves that curl around and are fused to enable the
plant to hold rainwater. The inside of the leaves contain nectar glands
and bright colors that attract insects, as well as hundreds of fine hairs
and a slippery cell layer that make it difficult for insects to climb out.
The insects eventually slide or fall into the liquid contained in the
leaf, and are digested by enzymes secreted by the plant. Some carnivorous
insects are adapted to survive inside the pitcher plant, and take
advantage of the plants ability to attract other insects.
Sundews have a
sticky flypaper like substance on hairs attached to their leaves. Like the
pitcher plants, the scent and color of the sundew leaves draws insects to
the plant. The two species of sundew most common in peatlands are the
round-leaved sundew (Drosera rotundifolia) and the spatulate-leaved
sundew (Drosera intermedia).
Bladderworts are more active in their feeding strategy. This plant has submerged tiny sacs (bladders), that inflate rapidly and suck in tiny aquatic organisms passing through the water. The bright, cheerful yellow flowers of the bladderwort seem to contradict its predatory nature!
Trees often show unusual growth forms in peatlands, particularly in more open areas of bog where peat layers are often thickest. Because of the decreasing nutrient levels, trees become more stunted in growth as fens transition into bogs. For example, some black spruce trees that are only six feet tall may be 80 years old. The needle-dropping tamarack, or larch, are more dominant in fens. White pine, on the rare occasion when it is found in a peatland, will often have a yellow-green appearance to its needles.
Orchids, with their elegant stalks and showy flowers, contrast with
the thick-leaved shrubs and spiky sedges. These exceptionally fragile
flowers have also adapted to the unusual growing conditions found in
bogs.
Yellow lady's slipper (photo: Ron Davis).
LIST OF COMMON PEATLAND PLANTS