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Very few studies assess the recovery of black ash on burned sites. This may be
because the wet niches occupied by black ash do not burn often. Following a
mid-May fire near Tower, Minnesota, in 1992, burned sites were compared to nearby
harvested sites. Logged sites were within 9.3 miles (15 km) of the burned sites and matched
burned sites "to the extent possible." The fire burned in quaking
aspen-dominated woodlands, but fire severity was not reported. Black ash made up
13% of the total number of live trees on burned sites sampled in the
summer of 1994. However, black ash was not among the 9 living species
on logged sites. Without predisturbance data, it is not possible to say that
black ash fared better on burned than logged sites [109].
In northern Cook County, Minnesota, an August wildfire burned in a 73-year-old
jack pine (Pinus banksiana)-black spruce forest. Severity of the fire was
not reported, but researchers noted that black ash was present in the
forests before and after the fire. Researchers took no measurements or made no
estimates of black ash's pre- or postfire distribution [6].
In riparian areas northeast of Thunder Bay, Ontario, the presence of black
ash was a significant (p=0.05) indicator of sites adjacent to areas burned in 1999.
The fire did little damage to riparian vegetation but "consumed"
all but a few remnant trees in the upland boreal mixed woods and
conifer-dominated forests. Black ash occurred on just 7% of sampled sites, so
statistical significance may be related to the fire's clearing effect but may be
what the authors describe as "a statistical artifact" [74].
This description provides characteristics that may be relevant to fire ecology,
and is not meant for identification. Keys for identification are available
[20,51,85,101,110,118,121,141].
Black ash is a native tree described by some as the "slenderest broadleaf tree in the
forest" [26]. 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 [26,59]. Branches do not
appear until high up on the trunk; tall trees may be
without branches for up to 50 feet (15 m) [26,118]. The
narrow trunk is rarely more than 2 feet (0.6 m) in diameter and is often leaning or bent
[59]. Black ash bark is soft with shallow grooves that give a scaly or
flaky appearance [20,51,59,118].
The shallow, spreading black ash root system makes this species prone to
windthrow [39,59]. Fine roots that measure between
0.1 and 0.4 mm in diameter are long and rarely branch [23]. A discussion of black ash mycorrhizal root associations is
available [80], as is an in-depth investigation of the
microscopic appearance of black ash roots that may be useful in identification [23].
The perfect and/or unisexual black ash flowers are described as tightly packed
panicles or racemes and arise from leaf scar axils produced the previous year
[20,51]. The opposite leaves are 10 to 16 inches (25-40 cm) long and pinnately
compound [51,59,110,118]. Leaflets often occur in groups of 9 but may number 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 [20,51,59,118,121]. The black ash fruit is a sometimes twisted samara most
often containing 1 seed but sometimes containing 2 or 3 seeds [20,51,110]. The fruit measures 1 to
1.5 inches (2.5-4 cm) long and is produced in clusters [59,112,118,121]. Often fruits have a
spicy odor [112].
Life span:
Black ash is a long-lived tree with a relatively rapid growth rate [122]. Heinselman [57] suggests that the typical life span
of black ash is 150 years. However, many black ash trees on the edges of Lake Duparquet in northwestern Quebec
were over 200 years old, and the oldest tree in the area was 319 years old
[127]. In northeastern Minnesota, several black ash trees in relatively pure stands were 250 year old.
At 100 years old, black ash trees can be between 39 and 75 feet (12-23 m).
Height is not well correlated with age when trees are more than 80 to 100 years old [71].
Black ash occupies poorly drained swamps, bogs, woodlands, gullies, depressions,
lowlands, foothills, valley flats, and stream and lake shores throughout its
range [20,26,51,104,118]. In Michigan, black ash is found on shady soggy sites, with moderate
nutrient levels, where the weather is cool [19]. Black ash is described in
swamps and wet woodlands of Virginia's Blue Ridge Province [141]. In
the southern boreal region of Quebec, black ash occurs on floodplains, lowest
elevation terraces, and depositional flats with mineral
soils [35]. In Minnesota's Glacial Lake Agassiz region, black ash
populates peatland margins receiving minerotrophic waters [56].
Soils:
Black ash grows on moist to wet, deep, fertile, mineral or organic
soils [26]. Mottles and gleys are typical of soils supporting black
ash (referenced in [112]).
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 [104]. 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 [146].
Excessive moisture is tolerated by black ash [62], and growth is considered
best on sites receiving moving, aerated water with soil pH values between 4.4 and 8.2
[143]. On Quebec's Lake Duparquet floodplain, where black ash
occurs in pure stands, flooding records from 1915 to 1991 indicate that flooding
occurs between April 7 and July 13. Flooding
conditions last an average of 24 days and range between 0 and 65 days [127].
Several areas report more specific soil characteristics for black ash
habitats. In southeastern Wisconsin, the relative importance of black ash
is significantly ( p<0.05) greater on basin sites than floodplain sites. The basin
site soils had significantly lower (p<0.0001) pH and significantly higher
organic matter, calcium, and magnesium levels than floodplain soils [38]. In the Lake
Agassiz Peatlands of Minnesota, black ash grows in
rich swamp forests where the pH is 6 to 6.5, calcium and magnesium
concentrations are high, and the moderately decomposed peat layer can be 1 to 6 feet
(0.3-1.8 m) deep [55].
Northern Lower Michigan's black ash-alder swamps have an organic matter depth of
16±9 (s) inches (40±22
cm). The pH is 7.3±0.5 (4 inches (10 cm) below soil surface) and calcium and magnesium
concentrations are 55.8±7.2 ppm and 20.6±3 ppm, respectively [145].
In alder swamps of Chippewa County, Michigan, where black ash
occurs, soils are described as black mucks. These soils have a 10- to 11-inch-
(26-28 cm) deep organic layer, pH levels between
6.4 and 6.8, and dissolved oxygen levels of 1.9/mg to 2.0/mg. These alder swamps
remained wet until mid-July during the study [92].
Elevation:
Very few areas report black ash elevation tolerances. Kudish
[70] indicated that black ash occurs between 100 and 2,800 feet (31-853 m) in
the Adirondack uplands of New York. In a review, researchers suggest that black
ash occupies sites from sea level to the highest elevations in the northern part
of its range; in the southern portion of black ash's range it is restricted to
elevations above 2,000 feet (610 m) [143].
Weather:
Black ash grows in regions with continental climates. Wright
[143] described black ash habitats as humid, receiving between 20 and 45 inches (510-1,140 mm) of
precipitation annually, having average
low January temperatures of 0 to 32 °F (-18
to 0 °C), reaching an average high temperature of 70
°F (21 °C)
in July, receiving annual snowfall levels of 30 to 100 inches (760-2,540 mm), and
typically having 80 to 180 frost-free days [143].
Some suggest that weather events during the
previous and current year's growing season of black ash are significantly (p<0.05) related to radial growth.
In the Lake Duparquet region of northwestern Quebec, researchers found that
April and May temperatures and August precipitation in the previous year positively
affected radial growth in black ash. However, precipitation in
the previous April, May, June, and October was negatively associated with
radial growth. In the same growing year, April temperature and June
precipitation were positively correlated with radial growth, but July
precipitation was negatively correlated with black ash radial growth [125].
Information was slightly different when flooded and nonflooded
sites were compared. On floodplain sites, growth was not generally affected by
temperature, but precipitation in the previous year's August and June and
the current year's December positively affected radial growth. On nonflooded sites,
radial growth was negatively correlated with the previous year's August temperatures and the
same year's May temperatures. The aforementioned relationships were significant
(p<0.05) [126].
Number found in balsam fir-black ash habitat type
Total number found
% of total found in balsam fir-black ash habitat type
Black ash is recognized as a dominant species in the following vegetation
classifications:
IL: Horseshoe Bottom Nature Preserve [75]
MI: northern Lower [145]
MN: Voyageur National Park [72]
Northeastern U.S.: [47,104]
WI: [30]
MB: [146]
NS: Saint Lawrence River Valley [32]
southeastern Canada: [47,104]
American elm (Ulmus americana) is listed as a codominant in many black
ash habitat and community type descriptions. It is important to note that many
American elm populations declined considerably following the
introduction of Dutch elm disease in the early 1930s. Some black ash habitat types and community
descriptions are from dated literature, and the presence of American elm may be
exaggerated in studies that predate population losses to Dutch elm disease.
Black ash-American elm-red maple forest cover type: 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 (Q. 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 (B. lenta), paper birch (B. papyrifera), gray birch (B.
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 (U. rubra), rock elm (U. thomasii), yellow birch,
black tupelo, sycamore, eastern hemlock (Tsuga canadensis),
and bur oak (Q. macrocarpa) [104]. 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 [39].
Northeastern U.S. and eastern Canada:
Black ash is common to many
deciduous, coniferous, and mixed lowland forest types in the eastern U.S. and
Canada.
In the northern Great Lake states, the greatest black ash biomass production is
reported for elm-ash-maple (Ulmus-Fraxinus-Acer spp.) forests.
Black ash biomass yields are 2nd greatest in northern white-cedar
(Thuja occidentalis) forests and 3rd greatest in balsam fir forests [113]. Tamarack (Larix laricina),
balsam fir, northern white-cedar, and red maple are found with black ash in
lowland spruce-fir forests of New England, the Great Lake states, and the boreal
region of Canada [12,42]. Black spruce-speckled alder (Alnus rugosa)
communities are typical of water-logged soils
in eastern Canada, the northern Great Lake states, and Maine [31]. Red spruce (P. rubens)-balsam fir
vegetation types extending
as far south as West Virginia and as far north as maritime provinces of Canada
may include black ash trees [52].
Black ash usually comprises less than 20% of the basal area in sugar maple
(Acer saccharum)-dominated vegetation in the
Great Lake states, New York, New England, Ontario, Quebec, and portions of the
Appalachians. In eastern Canada, black ash
occupies sugar maple-yellow birch habitats [48]. In northern Wisconsin, upper Michigan, southern Ontario, and southern Quebec
black ash is a "less common associate" of the eastern hemlock-yellow birch vegetation type
that grades into black ash-American elm-red maple forests on wetter sites [47].
In wet calcareous mixed woods of the maritime provinces, black ash is dominant,
and eastern white-cedar and red maple are both typical. These forests occur on
poorly drained
organic soils. In the early 1800s, black ash occurred in these
forests with 6.5% frequency, but in 1993 the frequency of ash was less than 1%. Land clearing,
wetland drainage, and tree harvest practices of European settlers are at
least partially responsible for the decline in black ash habitat [78].
Illinois: Black ash is common in Illinois' seep and swamp vegetation where silver maple
and green ash (F. pennsylvanica) are also typical [75].
Michigan: In northern Lower Michigan, seasonally flooded black ash-alder (Alnus
spp.) swamps experience extreme daily and seasonal temperature changes. Black ash also occupies hardwood swamps
where basswood (Tilia americana) and northern white-cedar are typical.
Hardwood swamps are also seasonally flooded but do not occur in frost pockets. The
basal area of black ash in black ash-alder swamps is 7.1±13.1
(s) m²/ha and in hardwood swamps is 6.1±6 m²/ha [145].
In the Indian Bowl area of southwestern Michigan, black ash occurs in tamarack swamps,
thought to be an earlier stage of succession to southern hardwood forest. The Indian Bowl is
frequently flooded, has organic soils high in calcium, and occupies elevations
of 600 to 750 feet (183-229 m) [68]. On the Isle Royale, black ash occurs in 40-year-old
paper birch-aspen (Populus spp.)-white spruce (Picea glauca)
stands that revegetated burned areas after a late July fire in 1963 [54].
Minnesota: In Voyageurs National Park, researchers recognize 2 vegetation
types dominated by black ash. The black ash-elm/trillium
(Trillium ssp.) type occupies moist sites, with deep nutrient-rich
soils. This type is uncommon but is considered climax. The black ash/yellow
marsh marigold (Caltha palustris) habitat
type is a climax type on sites that are better drained
than those occupied by black ash-elm/trillium [72]. Buell and
Bormann [24] recognize a stable basswood-balsam fir-black ash vegetation type
on poorly drained sites of Minnesota's Red Lake Indian Reservation.
In the Lake Agassiz Peatlands of Minnesota, black ash dominates the
overstory of swamp forests that lie on peatland edges and receive mineral-rich
water. Other typical species may include northern
white-cedar, tamarack, black spruce, and speckled alder [55]. In
the Boundary Waters Canoe Area, black ash occurs with low frequencies in balsam fir-paper birch and
red maple-quaking aspen (Populus tremuloides)-paper birch communities [88].
New York: Black ash is common in swamps and on floodplains of New
York. In the Adirondacks, black ash occurs in black spruce swamps. Small
northern white-cedar, tamarack, and red maple trees also populate these
sites [10]. Red maple dominates the hardwood swamps
in poorly drained depressions with inorganic soils throughout New York. Black ash,
American elm, swamp white oak, butternut (Juglans cinerea)
and/or bitternut hickory (Carya cordiformis) may also associate with red
maple hardwood swamps. Green ash, red maple, slippery elm, American hornbeam (Carpinus
caroliniana), and northern white-cedar may associate with black ash in lowland sites along the Hudson River.
Along rivers and lake shores of central and western New York where conditions
are uniformly wet and seasonal water fluctuations are low, silver maple-ash swamps are
common. Silver maple often makes up
70% of the canopy cover, but black ash, green ash, and white ash are also typical [97]. Huenneke [60]
describes black ash in the
eastern hemlock-yellow birch-red maple
wet vegetation type near Cayuga Lake.
Ohio: Black ash is a dominant species in closed-canopy lowland forests
at an average elevation of 860 feet (262 m) in central Ohio; other common
species are American elm, honey-locust (Gleditsia
triacanthos), and pin oak [16]. Braun [20] describes
black ash in northern coniferous forests, eastern hemlock-pine (Pinus
spp.)-northern hardwood forests, and beech-maple forests of Ohio. On poorly drained sites
that are part of northwestern Ohio's Black Swamp, black ash occurs with silver
maple, green ash, American elm, bur oak, and shellbark hickory (Carya laciniosa) [17].
In swamp forests of west-central Ohio's Cedar Bog,
northern white-cedar, red maple, black
ash, and yellow-poplar (Liriodendron tulipifera) dominate the overstory [27].
Pennsylvania: Black ash occurs in the pin oak-sweet gum (Liquidambar
styraciflua) forest cover type
in Gettysburg National Military Park and Eisenhower National Historic Site in
south-central Pennsylvania [144].
Vermont: In eastern hemlock-northern hardwood forests of central Vermont, sugar
maple, beech, white ash, and yellow birch dominate the canopy, but black ash,
basswood, eastern hemlock, and American elm also populate the canopy [18].
Wisconsin: In the black ash-yellow birch-eastern hemlock hardwood swamps
of Wisconsin's northern lowland forests, black ash is a mid-sized tree (45-70 feet
(14-21 m)) with a narrow crown [30]. In northern white-cedar-balsam fir-black ash swamps of northern
Wisconsin, black ash is most important on compacted organic soils that are inundated for much of the growing
season [25]. Winget and others [140] describe black ash, northern
white-cedar, and yellow birch communities on very poorly drained, black muck soils in
northern Wisconsin where even in mid-summer the ground water is just 12 inches
(3 cm) beneath the soil surface. Black ash is occasional in southern Wisconsin's
elm-ash savannah that is restricted to wet meadow sites. Important
canopy species include silver maple, river birch (B. nigra), green ash,
and swamp white oak [21].
Manitoba: Black ash is now the dominant overstory species in hardwood and
mixed hardwood forests of Manitoba that were dominated by American elm in the past.
Boxelder (Acer negundo) often dominates the subcanopy layer. This
community occurs along small stream floodplains on deep, loamy-clay soils with poor to very poor
drainage [146].
In the early 1970s, black ash colonized the Portage la Prairie
grassland area of Manitoba. While this area experiences periodic spring
flooding, it does not support the wet conditions most often associated with the
distribution of black ash. The successful establishment of black ash in prairie
grasslands suggests that high moisture levels are not the only factor limiting
the range of black ash. Other tree species associated with the Portage la
Prairie include bur oak, American elm, green ash, and red-osier dogwood (Cornus sericea
ssp. sericea) [102].
Several black ash hybrids and cultivars are used in ornamental landscapes [33].
Information on improving the growth of ornamental black ashes is
available [73]. Williams and Hanks [138] discuss many aspects
of growing black ash commercially; information is included on seed collection,
seed storage, germination, planting, protecting, and lifting.
Black ash wood
splits into slats easily, making it ideal for basketry [59]. Native people of northeastern Canada and the United
States historically and currently 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 baskets [108].
Wood Products:
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 [26]. The grain is coarse, sapwood is almost
white, and heartwood is dark in older trees [26,59]. Wood is used in making cabinets, veneer, paneling, short tool handles,
baskets, and indoor furniture [26,59,131].
Treated black ash wood is also used for posts. A study found, however, that
oil-treated posts outlast untreated posts. Trees cut in the spring were peeled, air dried
to 15% to 25% moisture content, and treated with 5% pentachlorophenol oil solutions.
Posts soaked in oil for 24 hours lasted 33 years, while untreated posts lasted just 4.5 years [64].
Black ash is capable of sexual and asexual reproduction. Asexual regeneration
typically follows top-kill and is through vegetative stump or root crown sprouting [39,77,112].
Breeding system:
Black ash can produce perfect or separate male and female flowers [20,51].
Hosie [59] suggests that male, female, and bisexual flowers can occur on a single tree.
In the northeastern U.S., the smallest tree to flower was 3 inches
(8 cm) in diameter [142].
Pollination:
Ashes are wind pollinated [142].
Seed production:
Large viable seed crops are produced intermittently by black ash. The ability to produce seed
occurs when trees are 30 to 40 years old [57]. In a review, Sims
and others [112] report that good crops of seed are produced at 1- to 8-year intervals.
Similarly, Sutherland and others [122] suggest 5 or more years pass between
good black ash seed production. For 25 years, researchers monitored black ash
seed production in northeastern Wisconsin. They found that seed production was
61% to 100% of full crop for 28%
of this time but was less than 36% of full crop for 68% of the time [49].
In 2 years of seed collection in southeastern Michigan, researchers collected
a total of 98,032 seeds from 42 different species. During the course of this study black ash failed to produce
any "potentially viable
seed" [83].
Seed dispersal:
The timing of fruit shed and weather conditions can affect the dispersal distances for black
ash seed. Sutherland and others [122] report that winds can transport seeds
328 feet (100 m) or more away from the parent tree. Curtis [30] called
winter-shed fruits "ice boats" and suggested that long-distance dispersal is
likely under these conditions. No actual distances were reported.
Seed banking:
Several researchers report that black ash seeds can remain viable for up to 8 years under natural
conditions [112,122].
Germination:
The germination of black ash seed is a multistage process of stratification and scarification
that often takes 2 to 3 years under
natural conditions [30,112]. The embryo
is immature when seeds are shed and requires warmth and moisture to fully develop.
When fully ripe, the embryo is still dormant and requires a cold, moist period to break
dormancy. Seeds germinate best on peat or mineral soils with high organic
content [30] and can germinate in litter or when covered by 0.5 to 0.75
inch (1-2 cm) of soil [39].
Steinbauer [116] conducted in-depth studies of black ash seed germination.
He found that at the time of seed shed the embryo is differentiated into the hypocotyl,
epicotyl, and cotyledons, but the embryo is just 1/2 to 2/3rd the size of the
seed. Embryos attain maximum size (0.5 inch (14 mm))
after 2 to 3 months at 68 °F (20 °C).
Germination does not immediately follow and is likely delayed by mechanical restrictions of the endosperm, suberized
layer, and/or seed coat. The digestion process necessary for germination is most efficient
after 2 to 3 months at 41 °F (5 °C). Higher temperatures (68-86 °F (20-30 °C))
allow the embryo to break mechanical barriers and
germination begins [116]. In the laboratory, maximum germination (87%) of black ash seed
occurred after seeds were ripened in peat moss for 18 weeks at 70 °F (21 °C) and then
exposed to 39 °F (4 °C) temperatures for 24 weeks [133,134].
Seedling establishment/growth:
Black ash seedlings establish under canopy shade on a variety of soils [122]. In
a review, Sims and others [112] report that 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 [112]. While seedlings can establish under a canopy, they
will eventually need canopy release for long-term survival [122]. Curtis [30]
reports that high densities of black
ash seedlings are rare [30]. Others suggest that grass and brush growth on the site can disrupt
successful establishment [39].
Bell [11] monitored the growth and mortality rates for an average of 6 black ash trees along Hickory Creek in
Illinois. Over the 18 years of the study, the average mean annual growth rate was 3.8±3
(s) mm/year and mortality was 3%±2.2%/year.
Researchers followed the establishment and
survival of black ash, green ash, and white ash seedlings in open meadows
and in upland and lowland young, successional, and closed-canopy forests of central Ohio.
Ashes made up
69.9% of the 2,553 seedlings monitored. Significantly more (p≤0.05) ash seedlings
emerged on lowland sites. Average ash seedling production
was 241±21(s x) new seedlings/100 m²/year
from 1984 to 1993. In 1988 and 1990, seedling production
peaked at approximately 800 to 1,000 new seedlings/100 m². Production in 1988 and 1990 was significantly
greater (p≤0.05) than for any other year. Peak production was not correlated
with any observed annual or seasonal climate
events, and the authors suggest that production peaks related to black ash's
masting behavior. The average life span of ash seedlings was 5
to 7 months. The seedling
population produced in June of 1990 was 916. By October of the same year, 66.7% were
dead; by May of 1991, 96.6% were dead. Survivorship was likely
affected by white-tailed deer browsing; deer occurred in densities of 0.6 to 0.7
animal/ha in the area [16].
Potential changes in growth:
Several factors may affect the growth rate and/or growth form of black ash. In open
canopy conditions, black ash exhibits a broader canopy than trees grown in
closed-canopy forests [26]. The growth rate of black ash
is slower on sites with organic peat and muck soils. Trees are just 30 to 45 feet
(9-14 m) after 50 years of growth and only 50 to 60 feet (15-18 m) in 100 years [39]. Immature plants severely
browsed by white-tailed deer may
develop a shrubby growth form. A single year free of browsing pressure, however, is enough to
allow production of a leader branch [30].
Asexual regeneration:
Vegetative reproduction is common following damage or top-kill [30]. 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 [39,112]. Black ash produces 7 to 17 stem sprouts when cut [77].
Asexual vs. sexual regeneration:
Along Lake Duparquet in northwestern Quebec,
researchers studied numerous characteristics of black ash's sexually and
asexually produced plants. In
this region, sprouts have higher and more constant mortality rates than
seedlings, and sexually reproduced stems reach older ages and produce larger diameters than
sprouts. Seedlings more often than sprouts reach
canopy height. However, on exposed flooded sites, new (1st-year and older)
seedlings experience higher mortality than sprouts, and vegetative reproduction
predominates. Likely, the more developed sprout root system allows for a more
rapid growth rate and an increased tolerance to flooding. Successful black ash seedling establishment
requires periods free of prolonged, intensive
flooding [127], but xeric conditions are not tolerated either [128].
Black ash is most typical of late successional communities. On wet or swampy
sites, black ash is often considered 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 [65]. Beech-maple
swamp forests near Cleveland, Ohio, where black ash is common, are considered
"climatic climax" communities [137]. In northern hardwood forests, the elm-ash
vegetation type may be the climax community on poorly drained sites [130].
Conway [28] describes 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 [112].
Black ash does not represent a climax species in all cases. In mixed
stands on moderately drained mineral soils black ash is regarded as a
"sub-climax" species [112].
The black ash-American elm-red maple cover type is a "temporary
climax" that typically succeeds to tamarack-black spruce
communities but is subsequently
replaced by northern white cedar [104]. Based on black ash's environmental tolerances, Graham [50] suggests
it cannot be a climax species in eastern hemlock-hardwood forests of Michigan's
Upper Peninsula. Because black ash does not often reproduce in thick
layers of decaying material and is only moderately shade tolerant, it cannot
be a climax species in eastern hemlock-hardwood forests.
The following studies suggest that black ash is a resilient and opportunistic
species regardless of disturbance type.
Fraxinus nigra (freixe negre) és és una espècie del gènere Fraxinus (freixes) nativa de gran part de l'est de Canadà i el nord-est dels Estats Units, des de l'oest occidental de Terranova fins al sud-est de Manitoba, i el sud d'Illinois i el nord de Virgínia.[1] Anteriorment abundant, a partir de 2014 l'espècie està amenaçada amb quasi l'extirpació total de tot el seu rang, com a resultat de la infestació per un insecte paràsit conegut com el barrinador maragda del freixe.
Fraxinus nigra (freixe negre) és és una espècie del gènere Fraxinus (freixes) nativa de gran part de l'est de Canadà i el nord-est dels Estats Units, des de l'oest occidental de Terranova fins al sud-est de Manitoba, i el sud d'Illinois i el nord de Virgínia. Anteriorment abundant, a partir de 2014 l'espècie està amenaçada amb quasi l'extirpació total de tot el seu rang, com a resultat de la infestació per un insecte paràsit conegut com el barrinador maragda del freixe.
Die Schwarz-Esche (Fraxinus nigra) ist eine Pflanzenart aus der Gattung der Eschen (Fraxinus) in der Familie der Ölbaumgewächse (Oleaceae).
Die Schwarz-Esche ist ein Laubbaum, der Wuchshöhen von bis 25 Meter erreicht. Sie hat eine graue, schuppig abblätternde Borke. Die Zweige sind rund und kahl. Die Winterknospen sind fast schwarz gefärbt. Die dunkelgrünen, unpaarig gefiederten Laubblätter bestehen aus sieben bis elf gesägten Fiederblättchen. Die Blätter riechen zerrieben nach Holunder.
Die Schwarz-Esche ist zweihäusig getrenntgeschlechtig (diözisch). Die Blüten stehen zu vielen in einem rispigen Blütenstand. Es gibt zwittrige und eingeschlechtige Blüten, die keine Kron- und Kelchblätter besitzen.
Die Chromosomenzahl beträgt 2n = 46.[1]
Das Verbreitungsgebiet der Schwarz-Esche reicht von den nordamerikanischen Eschen-Arten am weitesten nach Norden. Die Nordgrenze verläuft von Neufundland bis nach Südostmanitoba, die Südgrenze von Iowa über West-Virginia bis Delaware. Sie steigt bis auf Höhenlagen von 1050 Meter. Die Schwarz-Esche kommt auf nassen Böden in Auwäldern, in Mooren und Sümpfen vor. Sie bildet Mischwälder mit der Balsam-Tanne, Rot-Ahorn, Papier-Birke, Amerikanischer Ulme und Abendländischen Lebensbaum.
In Mitteleuropa ist sie winterhart und wird gelegentlich als Ziergehölz angebaut.
Das Holz der Schwarz-Esche besitzt einen dunkelbraunen Kern. Es ist weniger elastisch, leichter und weicher als das Holz von Rot-Esche und Weiß-Esche und ist deshalb weniger gefragt. Aus dünnen, schmalen Holzstreifen werden Körbe und Stühle geflochten und Fässer hergestellt. Es wird außerdem (häufig auch als Sumpfesche bezeichnet) in der Instrumentenherstellung, vorrangig bei E-Gitarren, verwendet.[2]
Die Schwarz-Esche (Fraxinus nigra) ist eine Pflanzenart aus der Gattung der Eschen (Fraxinus) in der Familie der Ölbaumgewächse (Oleaceae).
Fraxinus nigra, the black ash, is a species of ash native to much of eastern Canada and the northeastern United States, from western Newfoundland west to southeastern Manitoba, and south to Illinois and northern Virginia.[2] Formerly abundant, as of 2014 the species is threatened with near total extirpation throughout its range, as a result of infestation by a parasitic insect known as the emerald ash borer.
Black ash is a medium-sized deciduous tree reaching 15–20 metres (49–66 ft) (exceptionally 26 metres (85 ft)) tall with a trunk up to 60 cm (24 inches) diameter, or exceptionally to 160 cm (63 inches). The bark is grey, thick and corky even on young trees, becoming scaly and fissured with age. The winter buds are dark brown to blackish, with a velvety texture. The leaves are opposite, pinnately compound, with 7–13 (most often 9) leaflets; each leaf is 20–45 cm (8–18 in) long, the leaflets 7–16 cm (2+3⁄4–6+1⁄4 in) long and 2.5–5 cm (1–2 in) broad, with a finely toothed margin. The leaflets are sessile, directly attached to the rachis without a petiolule. The flowers are produced in spring shortly before the new leaves, in loose panicles; they are inconspicuous with no petals, and are wind-pollinated. The fruit is a samara 2.5–4.5 cm (1–1+3⁄4 in) long comprising a single seed 2 cm (3⁄4 in) long with an elongated apical wing 1.5–2 cm (5⁄8–3⁄4 in) long and 6–8 mm (1⁄4–5⁄16 in) broad.[3][4][5]
Black ash commonly occurs in swamps,[5] often with the closely related green ash. Its fall foliage is yellow. Black ash is one of the first trees to lose its leaves in the fall. It is very closely related to Manchurian ash, and will easily hybridize with it. Some consider the two to be geographic isolates of each other.
The species was considered abundant and its survival of little concern prior to the invasion of the emerald ash borer, first detected in North America in 2002. However, since that time this invasive insect has spread throughout most of the tree's range, and within a few years black ash is expected to be all but extirpated; a similar fate awaits green ash. In 2014, a U.S. Forest Service agent estimated that "ninety-nine percent of the ashes in North America are probably going to die." Blue ash and white ash are only slightly less affected.[6]
This wood is used by Native Americans of the North East for making baskets and other devices. The Shakers also made extensive use of the black ash for creating baskets. Also called basket ash, brown ash, swamp Ash, hoop ash, and water ash. It is also a popular wood for making electric guitars and basses, due to its good resonant qualities.[7]
Black ash is unique among all trees in North America in that it does not have fibers connecting the growth rings to each other.[8] This is a useful property for basket makers. By pounding on the wood with a mallet, the weaker spring wood layer is crushed, allowing the tougher and darker summer wood layer to be peeled off in long strips. The long strips are trimmed, cleaned, and used in basket weaving. Indigenous peoples of the Northeastern Woodlands also make bark baskets from black ash, traditionally used for berry-gathering.[8]
North American native ash tree species are used by North American frogs as a critical food source, as the leaves that fall from the trees are particularly suitable for tadpoles to feed upon in ponds (both temporary and permanent), large puddles, and other water sources.[9] Species such as red maple, which are taking the place of ash, due to the ash borer, are much less suitable for the frogs as a food source—resulting in poor frog survival rates and small frog sizes.[9] It is the lack of tannins in the American ash variety that makes them good for the frogs as a food source and also not resistant to the ash borer. Varieties of ash from outside North America typically have much higher tannin levels and resist the borer. Maples and various non-native invasive trees, trees that are taking the place of American ash species in the North American ecosystem, typically have much higher leaf tannin levels.[9] Ash species native to North America also provide important habitat and food for various other creatures that are native to North America, such as the long-horned beetle, avian species, and mammalian species.[10] Black ash is a food plant for the larvae of several species of Lepidoptera; see List of Lepidoptera that feed on ashes.
Fraxinus nigra, the black ash, is a species of ash native to much of eastern Canada and the northeastern United States, from western Newfoundland west to southeastern Manitoba, and south to Illinois and northern Virginia. Formerly abundant, as of 2014 the species is threatened with near total extirpation throughout its range, as a result of infestation by a parasitic insect known as the emerald ash borer.
Fraxinus nigra Marshall, fresno negro, es una especie arbórea perteneciente a la familia Oleaceae.
Es una árbol nativo del este de Canadá y nordeste los Estados Unidos, desde el oeste de la Isla de Terranova hasta Manitoba, y sur a Illinois y norte de Virginia.[1]
Es un árbol de tamaño mediano, caducifolio que alcanza los 15–20 m (excepcionalmente 26 m) de altura con un tronco de hasta 60 cm (excepcionalmente 160 cm) de diámetro. La corteza es de color gris, espesa, incluso en los árboles jóvenes, convirtiéndose en escamosa y fisurada con la edad. Los brotes de invierno son de color marrón oscuro a negruzco, con una textura aterciopelada. Las hojas son opuestas, pinnadas, con 7-13 (la mayoría de las veces 9) folíolos; cada hoja tiene 20–45 cm de largo, los folíolos 7–16 cm de largo y 2.5–5 cm de amplio, con un margen finamente dentado. Los folíolos son sésiles, adscritos directamente al raquis sin peciolo. Las flores se producen en la primavera, poco antes de las nuevas hojas, sueltas en panículas, tienen pocos o sin pétalos, y son polinizadas por el viento. El fruto es una sámara de 2.5-4.5 cm de largo con una sola semilla de 2 cm de largo con un ala alargada apical de 1.5–2 cm de largo y 6–8 mm de ancho.[2][3][4]
Comúnmente se desarrolla en los pantanos, a menudo con la estrechamente relacionada con Fraxinus pennsylvanica. En la caída de follaje es de color amarillo y es uno de los primeros árboles que pierden sus hojas en el otoño.
Es una planta de alimentación para las larvas de varias especies de lepidópteros; véase la lista de Lepidoptera que se alimentan de fresnos.
La madera es utilizada por los nativos americanos del Nordeste para hacer canastas y otros dispositivos domésticos. Los Shakers también hicieron un amplio uso de la especie para la creación de canastas. También llamada canasta Ash, Brown Ash, Pantano Ash, aro de ceniza, agua y cenizas. También es una popular madera para hacer guitarras y bajos, debido a sus buenas cualidades resonantes.[5]
Fraxinus nigra fue descrita por Humphry Marshall y publicado en Arbustrum Americanum 51. 1785.[6]
Ver: Fraxinus
nigra: epíteto latíno que significa "negra"[7]
Datos: Q1790101
Multimedia:
Especies: Fraxinus nigra
Fraxinus nigra Marshall, fresno negro, es una especie arbórea perteneciente a la familia Oleaceae.
Fraxinus nigra
Le Frêne noir[1] (Fraxinus nigra) est une espèce d'arbres de la famille des Oleaceae. Il est originaire d'Amérique du Nord.
Il est aussi connu sous les noms de frêne de grève et de frêne gras[1].
Autrefois très abondante dans les forêts et villes du Nord-Est américain, cette espèce est aujourd'hui considérée, avec le frêne bleu et le frêne blanc, en danger critique d'extinction par l'UICN[2]. La raison de ce déclin est l'arrivée d'une espèce exotique de coléoptères appelée agrile du frêne et dont l'invasion a tué plusieurs millions de frênes ravageant ainsi les populations du Canada et des États-Unis[2],[3]. En 2014, le Service des forêts des États-Unis estimait que l'invasion de l'agrile du frêne pourrait décimer 90% des frênes nord-américains[4].
En Amérique du Nord, cet arbre fait partie des traditions de nombreux peuples autochtones en vannerie (ex. tressage de panier), notamment les Abénakis, ou les Mohawks (anglais). En effet, une fois abattu, il est possible d'en tirer de longues éclisses, à la fois malléables et résistantes.
Ce petit arbre avec une couronne étroite a une écorce gris clair qui est molle et ressemble à du liège lorsque l’arbre est jeune, et s’écaille avec l’âge. Les folioles de forme ovale qui composent les tiges centrales sont de couleur vert foncé et saillantes. Les feuilles entières, contrairement aux folioles simples, ont tendance à tomber à l’automne[5].
Fraxinus nigra
Le Frêne noir (Fraxinus nigra) est une espèce d'arbres de la famille des Oleaceae. Il est originaire d'Amérique du Nord.
Il est aussi connu sous les noms de frêne de grève et de frêne gras.
Autrefois très abondante dans les forêts et villes du Nord-Est américain, cette espèce est aujourd'hui considérée, avec le frêne bleu et le frêne blanc, en danger critique d'extinction par l'UICN. La raison de ce déclin est l'arrivée d'une espèce exotique de coléoptères appelée agrile du frêne et dont l'invasion a tué plusieurs millions de frênes ravageant ainsi les populations du Canada et des États-Unis,. En 2014, le Service des forêts des États-Unis estimait que l'invasion de l'agrile du frêne pourrait décimer 90% des frênes nord-américains.
En Amérique du Nord, cet arbre fait partie des traditions de nombreux peuples autochtones en vannerie (ex. tressage de panier), notamment les Abénakis, ou les Mohawks (anglais). En effet, une fois abattu, il est possible d'en tirer de longues éclisses, à la fois malléables et résistantes.
Svartaskur (fræðiheiti: Fraxinus nigra) er tegund af aski sem vex í stórum hluta Kanada og Norðaustur-Bandaríkjunum, frá vesturhluta Nýfundnalands vestur til Suðaustur-Manitoba, og suður til Illinois og Norður-Virginíu.[2] Var áður algengur en hefur á síðari árum fækkað mjög vegna sníkjudýrsins Agrilus planipennis.
Svartaskur er meðalstórt tré, 15 til 20 m hátt með um 60 cm stofnþvermál, eða einstaka sinnum allt að 160 cm í þvermál. Börkurinn er grár, þykkur og svampkenndur, jafnvel á ungum trjám, og verður hreistraður og sprunginn með aldri. Vetrarbrum eru dökkbrún til svört, með mjúkri áferð. Blöðin eru gagnstæð og samsett með 7–13 (oftast 9) smáblöðum. Hvert blað er 20-45 cm langt, smáblöðin eru 7-16 cm löng og 2,5–5 cm breið, með fíntenntum jaðri. Smáblöðin eru stilklaus. Blómin koma að vori, rétt á undan blöðunum, í gisinni blómskipan, þau eru lítt áberandi og án krónublaða, enda vindfrjóvguð. Fræin eru 2,5-4,5 cm löng með væng.[3][4][5]
Svartaskur kemur oft fyrir í mýrum,[5] ósjaldan með hinum náskylda kvekaraaski (Fraxinus pennsylvanica). Haustliturinn er gulur. Svartaskur er ein af fyrstu tegundunum til að fella lauf að hausti í heimkynnum sínum. Hann er einnig mjög skyldur grænaski, Fraxinus mandschurica, og blandast honum auðveldlega. Eru jafnvel efasemdir um að þeir séu í raun aðskildar tegundir.
Svartaskur er fæða ýmissa fiðrildategunda (Lepidoptera).
Hann var eitt sinn talinn algengur og engar áhyggjur hafðar af verndun hans, en það var fyrir komu Agrilus planipennis, sem fannst fyrst í Norður Ameríku 2002. Hins vegar hefur þessi plága breiðst út um útbreiðslusvæði hans og innan fárra ára mun hann verða nær horfinn. Svipuð örlög bíða kvekaraasksins. Umboðsmaður "U.S. Forest Service" áætlaði 2014 að "níutíu og níu prósent asktrjáa í Norður Ameríku munu líklega deyja." Bláaskur og hvítaskur (Fraxinus americana) eru aðeins lítið eitt minna móttækilegir.[6]
Indíánar í norðaustanverðri N-Ameríku nota við hans í körfur og álíka. Hann er einnig vinsæll til að gera úr rafmagnsgítara og bassa vegna góðs hljómburðar.[7]
Svartaskur er nokkuð sérstakur meðal trjáa í Norður-Ameríku fyrir að vera án trefja sem tengja saman árhringina. Þetta kemur sér vel fyrir körfugerðarfólk. Ef barið er á timbrið með hamri kremst vorvöxturinn og dökkt sumarvaxtarlagið losnar frá í löngum renningum. Renningarnir eru jafnaðir og snyrtir og notaðir í körfugerð. Indíánar í skógum Norðaustur-Ameríku gerðu einnig körfur úr berkinum, sem venjan var að nota í berjatínslu.
Þessi tegund hefur lítið eitt verið reynd hérlendis og kelur lítið.[8]
Svartaskur (fræðiheiti: Fraxinus nigra) er tegund af aski sem vex í stórum hluta Kanada og Norðaustur-Bandaríkjunum, frá vesturhluta Nýfundnalands vestur til Suðaustur-Manitoba, og suður til Illinois og Norður-Virginíu. Var áður algengur en hefur á síðari árum fækkað mjög vegna sníkjudýrsins Agrilus planipennis.
Fraxinus nigra, atau Pohon Ash Hitam, ialah sejenis pohon ash terdapat di barat laut Amerika Syarikat dan di kebanyakan kawasan di Kanada timur, dari Newfoundland barat ke Manitoba selatan, dan ke selatan Illinois dan Virginia utara.
Svartask (Fraxinus nigra) er et løvfellende tre i oljetrefamilien.
Den blir som regel 15–20 m høy, men kan bli 26 m. Den vokser i fuktige skoger sammen med rødlønn, kvitalm og østamerikansk tuja. Den kan også finnes sammen med balsamgran, svartgran, canadahemlokk, gulbjørk og amerikalerk. Svartask er utbredt i østlige Nord-Amerika fra Manitoba og Newfoundland i nord sørover til Iowa, Indiana og Vest-Virginia.
En invaderende art, asiatisk askepraktbille (Agrilus planipennis), dreper svartask og andre amerikanske askearter, og svartask er derfor vurdert som kritisk truet på IUCNs rødliste.
Svartask (Fraxinus nigra) er et løvfellende tre i oljetrefamilien.
Den blir som regel 15–20 m høy, men kan bli 26 m. Den vokser i fuktige skoger sammen med rødlønn, kvitalm og østamerikansk tuja. Den kan også finnes sammen med balsamgran, svartgran, canadahemlokk, gulbjørk og amerikalerk. Svartask er utbredt i østlige Nord-Amerika fra Manitoba og Newfoundland i nord sørover til Iowa, Indiana og Vest-Virginia.
En invaderende art, asiatisk askepraktbille (Agrilus planipennis), dreper svartask og andre amerikanske askearter, og svartask er derfor vurdert som kritisk truet på IUCNs rødliste.
