Slippery Elm in Bloom

Color is slowly easing back into the deciduous woods.  Branches that were bare all winter are beginning to show the subtle reds, greens and yellows of early blooming trees and shrubs.

Slippery Elm (Ulmus rubra) in Bloom

Slippery Elm (Ulmus rubra) in Bloom

Slippery Elm (Ulmus rubra) is among the early flowering trees, often blooming sometime in March.  Before blooming, its rusty colored, fuzzy-hairy flower buds are visible throughout winter.

Slippery Elm (Ulmus rubra) Buds

Slippery Elm (Ulmus rubra) Buds

Slippery Elm blooms before its leaves appear, making it easier for the wind to carry Slippery Elm’s pollen to another flower, helping this species to achieve successful pollination. Wind pollination is a good evolutionary adaptation for an early blooming tree, since wind is a more reliable pollination partner in the usually cool blustery days of March than insects are.  (Although this spring is exceptionally warm in the Northeastern United States!)

Slippery Elm (Ulmus rubra) in Bloom

Slippery Elm (Ulmus rubra) in Bloom

Flowers that are successfully pollinated produce fruits that many birds eat, including Carolina Chickadees, Rose-breasted Grosbeaks, and Purple Finches.

Female Purple Finch. Purple Finches are among the birds that eat elm seeds

Female Purple Finch. Purple Finches are among the birds that eat elm seeds

Squirrels and other small mammals also eat Slippery Elm seeds.

Red Squirrel - a consumer of elm seeds

Red Squirrel – a consumer of elm seeds

Slippery Elm leaves are large and rough, with distinctly toothed edges.

Slippery Elm Leaf

Slippery Elm Leaf

These leaves provide food for many insects that in turn provide pollination services for other plants, or food for other animals. Over 200 species of butterfly and moth caterpillars (Leipidoptera), including those of Mourning Cloak, Question Mark and Eastern Comma butterflies and Polyphemous moths may eat the leaves of Slippery Elm and its close relatives.

Eastern Comma Butterfly

Eastern Comma Butterfly

Polyphemus Moth caterpillar, looking for a place to pupate. What a plump, juicy treat for a hungry bird!

Polyphemus Moth caterpillar, looking for a place to pupate. What a plump, juicy treat for a hungry bird!

Birds depend on these insects as protein for themselves and their growing offspring.

Male Black-throated Blue Warbler. Warblers, Chickadees, Titmice and most other birds depend on insects for a large percentage of their diet.

Cavity nesting birds or small mammals may find a suitable home site in Slippery Elm, while other birds, like Baltimore Orioles, may build their nests in its branches.

Natural cavity in a Slippery Elm. Some strings of nest material are draped below the opening.

Natural cavity in a Slippery Elm. Some strings of nest material are draped below the opening.

Slippery Elm gets its name from its inner bark (the phloem) which is part of the vascular system that transports food throughout the tree. Slippery Elm’s inner bark is mucilaginous (thick, sticky) and fibrous.  Indigenous North American peoples used the inner bark fibers to make rope or other cordage.

Slippery Elm’s inner bark has also been used to make a tea that is easy to digest and high in nutrients; it was given to people who had difficulty consuming food. The inner bark was also dried and ground to make a flour high in nutritional value.

Slippery Elm has many medicinal uses. As a demulcent it is well suited for treatment of inflamed mucous membranes throughout the digestive tract.  It also has anti-inflammatory and astringent properties, and has been used externally to treat skin problems including wounds, ulcers and boils.  Slippery Elm is available as an over the counter supplement, and has been approved by the Food and Drug Administration for use in throat lozenges.  Even plant-derived supplements can have unwanted side effects, so careful research or consultation with a physician should take place before consuming Slippery Elm.

Slippery Elm can be found in much of the eastern two-thirds of the United States and Canada, often in moist woods, stream banks, and woodland edges. Look for it blooming now in a natural area near you.

Slippery Elm (Ulmus rubra) in Bloom

Slippery Elm (Ulmus rubra) in Bloom

 

Resources

Beresford-Kroeger, Diana. Arboretum America: A Philosophy of the Forest.  2003

Eastman, John. The Book of Forest and Thicket.  1992.

Foster, Steven; Duke, James A. A Field Guide to Medicinal Plants and Herbs of Eastern and Central North America.  2000.

Hoffmann, David. Medical Herbalism.  2003.

Rhoads, Ann Fowler; Block, Timothy A. The Plants of Pennsylvania.  2007

Tallamy, Douglas W. Bringing Nature Home, 2007,

Illinois Wildflowers

USDA Database

 

 

Signs of Spring: Hazelnuts in Bloom

Beaked Hazelnut Flowers

Beaked Hazelnut Flowers

Need some reassurance that spring is on the way? Well, there may already be some shrubs blooming near you. Look for the flowers of my favorite harbinger of spring, American Hazelnut (Corylus americana), or its close relative, Beaked Hazelnut (Corylus cornuta). Hazelnuts can be found in rich woodlands, wood edges, thickets and along roadsides. They’re blooming down the road from me now.

American Hazelnut

American Hazelnut

With separate male and female flowers on the same plant, both species of hazelnut enlist the assistance of the wind in their pollination efforts. The flowers bloom before the leaves emerge, increasing the odds that the wind will successfully transport the pollen grains from the male flowers to a compatible female flower, since there are no leaf surfaces to impede the pollination effort.

Cream colored catkins containing the male flowers are visible from fall through winter, hanging stiffly from the hazelnut branches. As the winter winds down, the catkins grow longer and looser, their color evolving to include a hint of yellow. At maturity, thousands of tiny grains of pollen are released from the cluster of male flowers encompassed by the catkins, traveling on the wind in search of a female flower as a mate, preferably on a nearby compatible hazelnut. Pollination with a separate plant expands the gene pool, and increases the likelihood of successful offspring.

American Hazelnut Flowers

American Hazelnut Flowers

The female flowers are wonderfully gaudy in a subtle, inconspicuous way. Usually found at the tips of branches, the buds appear to be small and reddish brown during the winter. In bloom, the female flower parts resemble tiny, bright magenta sunbursts. Check the hazelnuts branches to see these petite, spidery female delights when the catkins containing the male flowers elongate and move freely in the wind.

American Hazelnut Female Flower

American Hazelnut Female Flower

If the flowers are successfully pollinated, nuts are produced, ripening by late summer. While the shrubs are fruiting these two species of Hazelnut are easily distinguished. The flowers of the two species are very similar, but the nuts have very distinctive coverings. American Hazelnuts have a leafy sheath with a ruffled edge.

American Hazelnut

American Hazelnut

Beaked Hazelnut’s coverings are long, tubular and beak-like, giving this species its name.

Beaked Hazelnut

Beaked Hazelnut

The nuts, also called filberts, are edible, although these North American species have generally not been grown as a commercial crop. A European species with larger nuts is grown commercially. Scientists from the Hybrid Hazelnut Consortium, whose members are Rutgers University, Oregon State University, Arbor Day Foundation and the University of Nebraska–Lincoln, are working to develop hybrid hazelnuts as a sustainable crop that can be grown in much of the United States and Southern Canada, to produce food, feed or bio-energy.

Humans are not the only consumers of hazelnuts. Squirrels, chipmunks, rabbits and fox are among the other mammals who eat these tasty treats. Birds with beaks strong enough to open the shells for a meal include woodpeckers, Blue Jays, Wild Turkey and grouse.

During their growing season, hazelnuts may provide food for many beneficial insects, including some of the most beautiful giant silkworm moths such as the Cecropia and Polyphemus Moths.

Polyphemus Moths Mating

Polyphemus Moths Mating

Beaked Hazelnut may also be used as food by Early Hairstreak butterfly caterpillars. According to Douglas Tallamy in Bringing Nature Home, over 130 species of butterflies and moths may use the hazelnuts as caterpillar food plants. Birds rely on these insects and others as an important source of protein, especially during the critical period when they are feeding their young families.

The fall color of the leaves may vary from yellow to deep reds. At Bowman’s Hill Wildflower Preserve, near New Hope, Pennsylvania, you can see the two species of hazelnut growing next to each other. At that location, the leaves of American Hazelnut turn luscious shades of red, peach and orange.

American Hazelnut in Fall

American Hazelnut in Fall

Beaked Hazelnut’s leaves at the same spot are bright yellow. Makes me wonder about the difference in their chemical make-up.

Beaked Hazelnut in Fall

Beaked Hazelnut in Fall

These multi-stemmed shrubs grow to a maximum height of about eight to ten feet, and can expand to a ten foot width. They make good candidates for a hedge row, either alone or with a mix of other shrubs. American Hazelnut can tolerate shade to sunny conditions, and moist, well-drained to dry soils. Beaked Hazelnut prefers a bit more sun.

American Hazelnut is native to the eastern two-thirds of the United States (except Florida), and to Quebec, Ontario and Manitoba provinces in Canada. Beaked Hazelnut’s native range includes the Canadian provinces from Newfoundland and Nova Scotia west to British Columbia, and much of the northern tier of the United States, southward in the east to Alabama and Georgia, and in the west to California.

See if you can find a hazelnut growing near you. When spring arrives, think about planting this versatile shrub to attract birds, butterflies, moths and other wildlife to your yard. It will also provide welcome assurance that spring is just about here.

Resources

Bringing Nature Home, 2007, Tallamy, Douglas W.

Butterflies and Moths of North America

USDA Plants Database

Hybrid Hazelnut Consortium

Hazelnut Research and Breeding at Rutgers University