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black ash (Fraxinus nigra)

























black ash
basket ash
swamp ash


SCIENTIFIC SYNONYMS: There are no scientific synonyms for
Fraxinus nigra.




TAXONOMY: The currently accepted scientific name of black ash is
Fraxinus nigra Marsh.


NATIVE STATUS: Native, United States and Canada.


tree described by some as the "slenderest broadleaf tree in the forest".
Black ash is normally a small tree just 40 to 60 feet (12-18 m) tall but can
reach 90 feet (27 m) in height. Branches do not appear until high up on the
trunk; tall trees may be without branches for up to 50 feet (15 m). The
narrow trunk is rarely more than 2 feet (0.6 m) in diameter and is often
leaning or bent. Black ash bark is soft with shallow grooves that give a scaly
or flaky appearance. The shallow, spreading black ash root system makes
this species prone to windthrow. Fine roots that measure between 0.1 and
0.4 mm in diameter are long and rarely branch. A discussion of black ash
mycorrhizal root associations is available, as is an in-depth investigation of
the microscopic appearance of black ash roots that may be useful in identifi-
cation. The perfect and/or unisexual black ash flowers are described as
tight- ly packed panicles or racemes and arise from leaf scar axils produced
the previous year. The opposite leaves are 10 to 16 inches (25-40 cm) long
and pinnately compound. Leaflets often occur in groups of 9 but may num-
ber 7 or 11. They measure 2 to 8 inches (5-20 cm) long by 0.6 to 2.4 inches
(1.5- 6 cm) wide. The black ash fruit is a sometimes twisted samara most
often containing 1 seed but sometimes containing 2 or 3 seeds. The fruit
measures 1 to 1.5 inches (2.5-4 cm) long and is produced in clusters. Often
fruits have a spicy odor. Black ash is a long-lived tree with a relatively rapid
grow- th rate; the typical life span of black ash is probably 150 years,
although much older specimens have been recorded (including one specimen
over 300 hundred years old).


REGENERATION PROCESSES: Black ash is capable of sexual and
asexual reproduction. Asexual regeneration typically follows top-kill and
is through vegetative stump or root crown sprouting. Black ash can pro-
duce perfect or separate male and female flowers. It is believed that male,
female, and bisexual flowers can occur on a single tree. Ashes are wind
pollinated; winds can transport seeds 328 feet (100 m) or more away from
the parent tree. Large viable seed crops are produced intermittently by
black ash. The ability to produce seed occurs when trees are 30 to 40 years
old. Several researchers report that black ash seeds can remain viable for
up to 8 years under natural conditions. Black ash seedlings establish under
canopy shade on a variety of soils. Seedling growth is rapid. Seedlings may
reach 2 inches (5 cm) in the first 2 weeks of growth. In 1 year, seedlings
are often 6 inches (15 cm) tall. Seedling survival is reportedly best at 45%
to 50% full sun conditions. While seedlings can establish under a canopy,
they will eventually need canopy release for long-term survival. High den-
sities of black ash seedlings are rare. Field observations suggest that grass
and brush growth on the site can disrupt successful establishment. This
latter point may be of special interest with Sky Meadows State Park; por-
tions of the park have very high densities of aggresive invasives (e.g.,
Japanese stiltgrass).


Vegetative reproduction is common following damage or top-kill. In reviews,
black ash is described as a "vigorous sprouter" following fire, browsing, or
cutting. Sprouts are produced from adventitious buds located on the sides
of stumps or root crowns. Black ash produces 7 to 17 stem sprouts when cut.


SITE CHARACTERISTICS: Black ash grows on moist to wet, deep,
fertile, mineral or organic soils. Mottles and gleys are typical of soils sup-
porting black ash. Soils associated with the black ash-American elm-red
maple cover type are wet mucks or shallow peat soils that are frequently
acidic with mid-levels of nutrients. In hardwood and mixed hardwood
vegetation types of Manitoba, black ash dominates the overstory. This
vegetation occupies deep, fine, loamy-clay soils with poor to very poor
drainage along small river floodplains. Excessive moisture is tolerated by
black ash, and growth is considered best on sites receiving moving, aerated
water with soil pH values between 4.4 and 8.2.


SUCCESSIONAL STATUS: Black ash is most typical of late succes-

sional communities. On wet or swampy sites, black ash is often consid-

ered a climax species. The black ash-American elm-balsam fir vegetation

type is "definitely climax" on peat soils in Itasca Park, Minnesota. Here

the dominant species are successfully regenerating and the community

appears stable. Beech-maple swamp forests near Cleveland, Ohio, where
black ash is common, are considered "climatic climax" communities. In
northern hardwood forests, the elm-ash vegetation type may be the
climax community on poorly drained sites. Black ash as an important
component of central Minnesota's oldest bog forests. Pure black ash
stands on wet organic soils in north-central Ontario are also deemed
climax. Powerful storms that blow down or damage trees are the most
common disturbance in black ash forest habitats. Little is reported on fire,
harvesting, or livestock grazing in these habitats. Black ash typically in-
creases following events that provide openings in the canopy.


Reviews of black ash indicate that initially black ash is moderately shade
tolerant but with increasing age, shade tolerance decreases. Researchers
have found that seedlings develop best under 45% to 50% of full sunlight


SEASONAL DEVELOPMENT: Spring flowers and fall fruits are typical
for black ash. Flowering occurs before black ash trees produce leaves.


GENERAL DISTRIBUTION: Black ash occurs in many north-
eastern U.S. states and in several of Canada's eastern provinces. The
northernmost portion of black ash's range extends from Newfoundland
to southeastern Manitoba. Populations in North Dakota mark the western
most distribution. Black ash occupies habitat in all of the Great Lake states
and reaches its southern limit in northern Virginia. Black ash apparently is
in retreat, being endanger of extirpation throughout much of its natural




Tree specimens can be found on trails marked in red.


       Bleak House
       Appalachian Trail/Old Trail
       South Ridge/North Ridge
Gap Run
       Woodpecker Lane

       Sherman's Mill
       Rolling Meadows/ Lost Mountain
       Fish Pond


poorly drained swamps, bogs, woodlands, gullies, depressions, lowlands, foot-
hills, valley flats, and stream and lake shores throughout its range. In Michi-
gan, black ash is found on shady soggy sites, with moderate nutrient levels,
where the weather is cool. Black ash is described in swamps and wet wood-
lands of Virginia's Blue Ridge Province. In the southern boreal region of
Quebec, black ash occurs on floodplains, lowest elevation terraces, and depos-
itional flats with mineral soils. In Minnesota's Glacial Lake Agassiz region,
black ash populates peatland margins.


The black ash-American elm-red maple (Acer rubrum) forest cover type
occurs throughout the northeastern United States and eastern Canada. Of
the 3 major species, black ash is most restricted to this vegetation type. In
the Great Lake states and the western Canadian Range, balsam poplar
(Populus balsamifera ssp. balsamifera), balsam fir (Abies balsamea), and
yellow birch (Betula alleghaniensis) are common to this cover type. Silver
maple (Acer saccharinum), swamp white oak (Quercus bicolor), sycamore
(Platanus occidentalis), pin oak (Quercus palustris), black tupelo (Nyssa
sylvatica), and eastern cottonwood (Populus deltoides ssp. deltoides) are
typical of the black ash-American elm-red maple forests of northern Ohio
and Indiana. In New England and eastern Canada, sweet birch (Betula lenta),
paper birch (Betula papyrifera), gray birch (Betula populifolia), silver maple,
and black spruce (Picea mariana) are common. The cover type in New York
is habitat for white ash (Fraxinus americana), slippery elm (Ulmus rubra),
rock elm (Ulmus thomasii), yellow birch, black tupelo, sycamore, eastern
hem- lock (Tsuga canadensis), and bur oak (Quercus macrocarpa). The
black ash-American elm-red maple cover type in northern Wisconsin and
the Upper Peninsula of Michigan is dominated by black ash. On very poorly
drained sites, stands are almost pure black ash, and black ash is considered
a climax species.


IMPORTANCE AND USES: While not recognized as an important food
source for wildlife, black ash is utilized in small quantities by a variety of
animals. In a review, black ash is recognized as an important seed source
for game birds, songbirds, and small animals, and is utilized as browse by
white-tailed deer and moose.


Black ash habitats are used seasonally by both American black bears and
bobcats. The presence of black ash may indicate valuable feeding sites for
American black bears in the Great Lakes region. The lowland grasses and
herbaceous vegetation associated with black ash swamps are a primary
early spring (April-May) food. Female bobcats selected lowland deciduous
forests as habitat in northwestern Wisconsin in the summer and the winter.
Black ash and alder (Alnus spp.) dominated the lowland forests.


American beavers, rabbits, and other small mammals occasionally feed
on black ash bark and stems. In Michigan's Upper Peninsula, American
beavers infrequently utilized black ash as a winter food source; however,
in North Dakota the small twigs and bark of black ash are preferred by
American beaver. On Mantioulin Island, Ontario, snowshoe hare use of
black ash was low in the winter season. Five percent of available stems
were browsed. In a guide to growing black ash in the Maritime Provinces,
mice from girdling stems of young black ash.


Although few studies highlight specific links between birds and black ash,
it is likely that the wetland habitats occupied by black ash are attractive to
many bird species. It is also likely that birds feed on black ash seeds. Black
ash was one of many species investigated in a caloric content study of seeds
eaten by birds. In Aitkin County, north-central Minnesota, 2 of 14 located
great gray owl nests were found in black ash trees. Black ash habitats are
important ruffed grouse roosting and brooding areas. Ruffed grouse used
black ash-dominated swamp hardwoods as winter habitat. Swamp hard-
woods made up 19% of the winter habitat use (number of plots with roosts/
total number of plots of this cover type), and an average of 1.3 roosts/plot
were found in black ash-dominated swamps. In the hot summer months,
swamps are important brood habitat.


Researchers found several frog species in balsam fir-black ash forests of
Itasca State Park, Minnesota. Researchers found a total of 855 frogs
throughout the 5 years of field studies conducted in mid-August. Of the
855 frogs, 270 occurred in the balsam fir-black ash habitat type. Micro-
climates, vegetation type and coverage, as well as potential escape areas
likely affected habitat choice.


Several black ash hybrids and cultivars are used in ornamental landscapes.

Black ash wood splits into slats easily, making it ideal for basketry. Native
people of northeastern Canada and the United States historically and cur-
rently use black ash in basket making. Black ash basketry is common in
Maine, New Brunswick, Nova Scotia, and New York. The Passamaquoddy,
Penobscot, Maliseet, Micmac, and Mohawk people utilize black ash in their


The wood from black ash trees is not particularly strong and is used mainly
for indoor furnishings. Black ash wood is moderately heavy; 1 air-dried
cubic foot weighs 34 pounds. The grain is coarse, sapwood is almost white,
and heartwood is dark in older trees. Wood is used in making cabinets,
veneer, paneling, short tool handles, baskets, and indoor furniture. Treated
black ash wood is also used for posts.



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