The Grassy Shrub Marsh is a plant community that exists in wetlands all across Maine. It is often a transitional area that merges with other plant communities near lakes, ponds, or streams. After spring flooding, water levels go down but the soil stays saturated throughout the rest of the season. The soil is slightly acidic and composed of minerals, sometimes with a thick layer of organic muck at the top.
As the name suggests, this plant community is dominated by grasses and shrubs in various proportions, with trees either loosely scattered or entirely absent. At least half of the plant biomass is herbaceous plants, especially grasses, sedges, and rushes such as Bluejoint and Three-way Sedge. Yellow Loosestrife is a wildflower indicator species for this plant community, and occasional ferns include Royal Fern and Sensitive Fern. There may be a very small proportion of moss species as well. The shrub layer is somewhat sparse, often consisting of various dogwoods, alders, Mountain Holly, and Meadowsweet. Other possible shrubs found here include Steeplebush, Sweetgale, and Leatherleaf. In southern Maine, Common Buttonbush frequently appears in Grassy Shrub Marshes.
This plant community is an important habitat for many species that require water. Beavers are a frequent inhabitant, often changing flooding patterns which can lead to a change in the structure of the vegetation. Sometimes this change is enough to turn the landscape into a different community!
The Grassy Shrub Marsh is also home to wading birds such as the Green Heron and American Bittern. Some rare birds use this habitat for nesting, including the Least Bittern and Sedge Wren. This wet habitant can also function as a vernal pool, where it supports Wood Frogs, Spotted Salamanders, and Blue-Spotted Salamanders. Rare reptiles rely on marshes like these, such as the Ribbon Snake, which hunts in densely vegetated waterside areas. Rare Spotted Turtles and Blanding’s Turtles can overwinter in patches of deep water.
To learn more about Willows and their plant communities, check out our upcoming Natural Communities Webinars and Nature Walks:
Natural Communities & Seasonal Change is a three-part spring learning series that combines monthly webinars with guided field experiences to explore Maine’s native plant communities through the lens of seasonal phenology. The series focuses on how native trees and shrubs signal ecological change, support wildlife, and shape both natural and human landscapes. Participants will build skills in observation, plant identification, and reading the landscape as spring unfolds.
April is for Willows:
Webinar on April 15, 5:30-7 pm
Natural Communities Visit: Willows at Gilsland Farm, Falmouth – April 16, 5:30-6:30 pm
Natural Communities Visit: Willows at Essex Nature Preserve, Bangor – April 18, 3-4pm
Here are some plants to look for in these communities:
Pussy Willow
One of the few trees that can be found in this plant community is the water-loving Pussy Willow. It thrives in the full sun of the Grassy Shrub Marsh, growing up to 15 feet tall and wide. Willows have shallow root systems that are excellent at holding together soil on waterbanks, and they produce suckers that can create large clonal stands. In addition, willows have fragile branches that easily snap in storms. A lucky branch that lands just the right way in the soil can produce a brand new, genetically identical tree! A good way to identify willows in winter is by looking at the buds—while most trees have buds that consist of many overlapping scales, willow tree buds only have one scale.
Different species of willow can be tricky to tell apart because the species tend to hybridize, and there is high variability in the shape and size of various features. Even Henry David Thoreau once said, “The more I study willows, the more I am confused!” However, for a couple of weeks of the year in early spring it becomes extremely easy to identify Pussy Willows. Look for the iconic white to gray fuzzy catkins in late March and early April. Male catkins are much larger than female catkins, and as the season progresses, they extend stamens with yellow anthers. The tiny seeds that form have a tuft of fluff for wind dispersal. They don’t last very long, oftentimes landing and germinating within a day.
This tree is named after the cat paw look of the fluffy catkins. One legend gives a delightful story for how the tree got its fluffy catkins: one day, a cat and her litter of kittens were playing alongside a river when the kittens accidentally fell in. The mother cat meowed for help, and the riverside Pussy Willow trees drooped down and caught the kittens in their branches, lifting them to safety. The fluffy catkins that emerge each spring represent the kittens that the trees saved that day!
Willow trees are an extremely useful resource for Indigenous peoples. The wood is flexible when freshly cut but hardens when it dries, making it ideal for crafting a variety of items including baskets, cooking tools, ropes, nets, arrow shafts, paintbrushes, fish traps, and boats. In addition, the inner bark and leaves of willow trees contain salicylic acid, the active ingredient in aspirin. Long before we had this pill, Indigenous peoples chewed or boiled willow parts for a painkiller and anti-inflammatory.
Historically, “willow water” was used to induce rooting in other species. Placing willow stems in water would infuse it with indolebutyric acid, encouraging growth in other trees before rooting hormones became commercially available. Pussy Willow is eager to grow, even when it is just a cut branch—it’s easy to clone from cuttings, and if placed in warm water in winter, it can flower early.
A myriad of species rely on Pussy Willows for food and shelter. In early spring, it is a favorite of honeybees, mason bees, sweat bees, and mining bees. It also supports lots of specialized species. Viceroy butterfly caterpillars munch on the leaves, rabbits and porcupine eat the buds and bark, and deer and moose browse the twigs. Pussy Willow thickets make great cover for songbirds and waterfowl in the Grassy Shrub Marsh. Catkin emergence timing perfectly aligns with Ruby-throated Hummingbird nest-building—the hummingbirds will often gather fluff from these catkins to line their nests.
Meadowsweet
Meadowsweet is an adaptable shrub that can be found in fields, on roadsides, or in swamps and wet meadows like the Grassy Shrub Marsh. It can form clonal stands that help maintain meadow habitats by crowding out trees, preventing them from establishing. It reaches a mature height of 3-4 feet with a cluster of unbranched reddish-brown stems. The leaves are alternately-arranged, thin, and slightly toothed. In midsummer, clusters of fragrant flowers bloom in fuzzy panicles. There are five petals to a flower, blooming white with hints of pink or orange. The green foliage turns golden yellow in the fall as the tough, brown fruit develops. The seeds will drop to the ground nearby or be distributed by animals. In areas like the Grassy Shrub Marsh, seeds can disperse by water as well, able to float for more than a week. The rusty brown seed heads that are left behind make this plant easy to identify in winter. Meadowsweet looks very similar to closely-related Steeplebush, but that plant has pink flowers and the leaves have silvery undersides.
Meadowsweet’s name is straightforward, combining the natural habitat of the plant and the fragrance of the flowers. It may also be named after a similar looking European plant used to make mead, originally called Mead-wort. Our native New England Meadowsweet has worth in making beverages too—Indigenous peoples brew tea from the leaves, and early settlers made a drink with the leaves and honey. They also used the branches as a pipe stem for smoking tobacco, giving it the nickname “Pipestem.” Similar to willows, this shrub contains salicylic acid, making it useful as a painkiller and anti-inflammatory. It responds well to pruning, and it makes a beautiful addition to a bouquet as a cut flower.
Animals make use of all parts of this plant! The flowers are a good nectar source for butterflies, bees, wasps, and beetles. It is also a host plant for some beetles and gall gnats. Songbirds eat the seeds and use the branches for nesting. Grouse have also been known to nibble on the buds, and rabbits and deer browse the branches.
Common Soft Rush
Common Soft Rush is the most widespread rush species in the world, found on every continent except Australia and Antarctica! It grows up to 4 feet tall in consistently moist or wet soil, so it is perfectly at home in a Grassy Shrub Marsh. It has upright, tubular, and dense stems that have the characteristic stiffness of rushes. However, they are not as stiff as the other rushes—their relative flexibility gives this plant its name. It has no leaves, but in summertime, inconspicuous flowers bloom on the side of the stems in reddish-brown clumps. It can spread both by self-seeding and through rhizomes.
Common Soft Rush has been put to use by many cultures around the world. In Japan, this plant was used to make tatami mats. Europeans soaked the stems in grease to use as a very cheap alternative to candles, called “rushlights.” Indigenous peoples around the world use the rush for knots and weaving. This plant makes an excellent addition to rain gardens, as it thrives in the wet environment, helps with erosion control, and is very tolerant to pollution.
At the intersection between aquatic and terrestrial life, Common Soft Rush is a crucial plant for both food and shelter. In standing water, it makes habitat for amphibians and spawning fish. Waterfowl shelter their nests amongst the stems, and wading feeders hunt for critters hiding in the water. This rush provides seeds and cover for rabbits, porcupines, gophers, moose, and muskrats. Muskrats will also eat the roots!
Join us!
April is for Willows
Webinar on April 15, 5:30-7 pm
Natural Communities Visit: Willows at Gilsland Farm, Falmouth – April 16, 5:30-6:30 pm
Natural Communities Visit: Willows at Essex Nature Preserve, Bangor – April 18, 3-4pm
