Green Ash

Scientific Name: Fraxinus pennsylvanica. Fraxinus is simply the Latin word for ash. The species name, pennsylvanica, means of Pennsylvania, one of the many states in which this species can be found.¹

Common Name: Green ash is the name most commonly associated with this tree, though it is sometimes called red ash as well. Just don’t get it confused with blue, black, white, or pumpkin ash. Those four, along with Biltmore and Carolina ash, are all different species of ash trees found in Virginia!²

Family: Oleaceae (Olive Family). Plants in the olive family are woody, have opposite branching and leaves, and their fruits can be a fleshy berry, drupe, dry capsule, or winged samara (maple trees have samaras—some folks call them “helicopters” or “whirligigs!”). Familiar members of this family include olives, lilacs, ashes, privets, and forsythias.²

Average Height: 50-70 feet

Description: These deciduous trees have straight trunks and a round to irregular crown. Their gray bark is thick and furrowed, and often forms a diamond pattern. Leaves are 6–14” long, opposite, and pinnately compound with 5–9 leaflets, but they most often have 7 leaflets. The green leaflets are elliptical or ovate, measure roughly 2–5” long and ¾–2” wide, and may be entire or toothed. Green ash is dioecious, meaning each tree has only male or female flowers. The purplish flowers have no petals and are pollinated by the wind. Fertile female flowers develop into long, narrow samaras, each with one seed attached to a papery wing. The wind also helps disperse the seeds when the samaras fly from the tree in fall or winter.^1,2,3,6

Bloom time: Apr – May

Notes: Two characteristics that distinguish Fraxinus pennsylvanica (green ash) from Fraxinus americana (white ash) are leaves with green undersides (as opposed to white) and a semi-circular leaf scar (as opposed to U-shaped).^3,6

Range: While common in the Piedmont and Coastal Plain of Virginia, Fraxinus pennsylvanica is absent from many counties in the west and southwest of Virginia, and is only found infrequently in the mountains, usually near streams.^2,9 It’s widespread throughout much of the United States and Canada, ranging from Nova Scotia and Quebec west to Alberta and Montana, and south as far as Texas and Florida.⁸

Geology/Soil: Prefers moist soils containing silt-loam or clay-loam. Can tolerate occasional flooding.³

Habitat: Most strongly associated with many types of wetlands. Found in floodplain forests, swamps, riverbanks, and wet flatwoods. May sometimes be found in old fields or moist upland forests.^2,3,9

Flora associations: Often found with a wide array of species that favor moist soils, including silver maple (Acer saccharinum), red maple (Acer rubrum), sycamore (Platanus occidentalis), boxelder (Acer negundo var. negundo), buttonbush (Cephalanthus occidentalis), poison ivy (Toxicodendron radicans), orange jewelweed (Impatiens capensis), false nettle (Boehmeria cylindrica), and dotted smartweed (Persicaria punctata).¹¹ Do you see any of these species here?

Fauna associations: Ash trees provide food for many types of insects—from caterpillar larvae of butterflies and moths to plant bugs, beetles, weevils, and scales. These insects may feed on the tree by boring into the wood, sucking on plant juices, or just munching on the leaves. A few species associated with ash trees are the woolly ash aphid (Prociphilus fraxinifolii), a flea beetle (Trichaltica scabricula), habilis underwing moth (Catocala habilis), a leaf blotch miner moth (Marmara fraxinicola), the waved sphinx moth (Ceratomia undulosa), and both the ash sphinx and great ash sphinx moths (Manduca jasminearum and Sphinx chersis).^3,4,12

Small mammals and birds such as wild turkeys, northern cardinals, and grosbeaks will eat ash seeds. White-tailed deer and moose may eat the twigs, and the American beaver and North American porcupine may eat the bark and wood. Although they have flowers, ash trees don’t have any pollinators—they are pollinated by the wind!^3,4

The emerald ash borer (Agrilus planipennis) is a wood-boring beetle native to Asia that was introduced to Michigan in the 1990s. It has spread widely within the range of ash trees (Fraxinus spp.) causing a rapid decline of ash populations as trees infested with the emerald ash borer often die within two years. The larvae feed on the tissues of the tree, creating S shaped tunnels under the surface of the bark. The tunnels are about ⅛” wide and may be filled with waste from the ash borer. The larvae then overwinter and pupate, with adults emerging in spring to early summer. The adults leave a D shaped exit hole when they emerge (most native borers have round or oval exit holes!). Aside from the exit holes, other outward signs that the tree may be infested include a thin canopy, new growth sprouting from the base of tree or main branches, and bark that is splitting or badly damaged by woodpeckers.^8,10 Look around—can you find any of these signs on the ash trees in the park?

Human associations: The wood of Fraxinus pennsylvanica is used to make a wide variety of items, from furniture to tool handles to sporting equipment. People from many Indigenous nations turn ash wood into bows and arrows, pipe stems, handles for tools, bats and hoops for games, splints for baskets, cradleboards, snowshoes, ceremonial poles, musical instruments, and lots of other things! Additionally, the Algonquin people use infusions of the bark to treat fatigue and depression.⁷

We want these plants to thrive and for everyone who gets to visit the park to enjoy them, so remember – don’t pick flowers or other parts of the plant!!

1 “Fraxinus Pennsylvanica – Plant Finder.” Www.missouribotanicalgarden.org, www.missouribotanicalgarden.org/plantfinder/plantfinderdetails.aspx?kempercode=a868. Accessed 6 Dec. 2024.

2 Weakley, A.S., J.C. Ludwig, and J.F. Townsend. 2012. Flora of Virginia. Bland Crowder, ed. Foundation of the Flora of Virginia Project, Inc., Richmond. Fort Worth: Botanical Research Institute of Texas Press, pp. 739-742.

3 “Green Ash (Fraxinus Pennsylvanica Lanceolata).” Illinoiswildflowers.info, 2024, www.illinoiswildflowers.info/trees/plants/green_ash.htm. Accessed 6 Dec. 2024.

4 “Search – Fraxinus Pennsylvanica.” Bugguide.net, 2024, bugguide.net/index.php?q=search&keys=fraxinus+pennsylvanica&search=Search. Accessed 6 Dec. 2024.

5 “Fraxinus Pennsylvanica (Green Ash, Red Ash, Water Ash) | North Carolina Extension Gardener Plant Toolbox.” Plants.ces.ncsu.edu, plants.ces.ncsu.edu/plants/fraxinus-pennsylvanica/. Accessed 6 Dec. 2024.

6 “Virginia Tech Dendrology Fact Sheet.” Vt.edu, 2021, dendro.cnre.vt.edu/dendrology/syllabus/factsheet.cfm?ID=48. Accessed 6 Dec. 2024.

7 “BRIT – Native American Ethnobotany Database.” Brit.org, 2024, naeb.brit.org/uses/search/?string=Fraxinus+pennsylvanica. Accessed 6 Dec. 2024.

8 “NatureServe Explorer 2.0.” Natureserve.org, 2024, explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.144657/Fraxinus_pennsylvanica. Accessed 6 Dec. 2024.

9 “Digital Atlas of the Virginia Flora | Fraxinus Pennsylvanica Marshall.” Vaplantatlas.org, 2024, www.vaplantatlas.org/index.php?do=plant&plant=2755&search=Search. Accessed 6 Dec. 2024.

10 “Symptoms and Signs of EAB.” Emerald Ash Borer in Wisconsin, 29 June 2011, eab.russell.wisc.edu/signs-and-symptoms/. Accessed 6 Dec. 2024.

11 “NatureServe Explorer 2.0.” Natureserve.org, 31 May 2024, explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.686717/Acer_(rubrum_saccharinum)_-_Fraxinus_pennsylvanica_-_Ulmus_americana_-_Boehmeria_cylindrica_Floodplain_Forest. Accessed 6 Dec. 2024.

12 Wagner, David L. Caterpillars of Eastern North America : A Guide to Identification and Natural History. Princeton, N.J., Princeton University Press, 2005.

Definitions:

Deciduous: Used to describe trees that lose their leaves.

Dioecious: Describes a species for which the flowers are unisexual—either male or female—and only one type of flower is present on an individual tree.

Entire: A leaf with an untoothed margin.

Pinnately compound: A leaf with leaflets arranged along a central axis.

Samara: A dry, winged fruit dispersed by the wind. The “helicopters” from maple trees are a good example of a samara.