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• Oleaceae
• Fraxinus
• Fraxinus nigra

Fraxinus nigra — black ash

Facts

Black ash is a slow-growing tree of northern wooded swamps. Though it rarely attains a wide girth, this slender tree can reach heights of 90 feet (27 m) or more. The species is dioecious; that is, male and female flowers are borne on different trees. It can also reproduce asexually by suckering. The fibrous, easy-to-split wood, is used for making baskets -- hence one of its common names, "hoop ash." Its seeds are important food sources for wetland birds.

Habitat

Floodplain (river or stream floodplains), forests, swamps

Characteristics

• Buds or leaf scars

  Bud position relative to scar

  the winter bud has a leaf scar just below it

  Bud scale number

  • there are three or more scales on the winter bud, and they overlap like shingles, with one edge covered and the other edge exposed
  • there are two scales on the winter bud, and their edges meet

  Bud scar shape (Fraxinus)

  the upper edge of the bud scar is straight across or slightly concave

  Bundle scar number

  5 or more

  Collateral buds

  there are no collateral buds on the sides of the branches

  Leaf scar arrangement

  there are two leaf scars per node on the stem or twig

  Superposed buds

  there are no superposed buds on the branch

  Terminal bud

  the branch has a terminal bud on it

  Winter bud scales

  the winter bud is perulate (partially or completely covered with one or more scales)

  Winter bud stalks

  the winter buds have no stalks

• Flowers

  Carpels fused

  the carpels are fused to one another

  Enlarged sterile flowers

  there are no enlarged sterile flowers on the plant

  Flower petal color

  NA

  Flower symmetry

  there are two or more ways to evenly divide the flower (the flower is radially symmetrical)

  Hairs on ovary (Amelanchier)

  NA

  Hypanthium present

  the flower does not have a hypanthium

  Inflorescence position

  the inflorescences grow on older branches

  Inflorescence type

  • the flowers grow out of the axil (point where a branch or leaf is attached to the main stem)
  • the inflorescence is a panicle (branched with the individual flowers on stalks)

  Number of pistils

  1

  Ovary position

  the ovary is above the point of petal and/or sepal attachment

  Petal and sepal arrangement

  the flower includes only one cycle of petals or sepals

  Petal appearance

  NA

  Petal fusion

  NA

  Sepal appearance

  NA

  Sepal cilia (Ilex)

  NA

  Sepal tip glands

  NA

  Sepals fused only to sepals

  NA

  Stamen number

  1 or 2

  Stamen position relative to petals

  NA

• Fruits or seeds

  Berry color

  NA

  Fruit type (general)

  the fruit is dry but does not split open when ripe

  Fruit type (specific)

  the fruit is an achene (dry, usually 1-seeded, does not separate or split open at maturity)

  Nut with spines (Fagaceae)

  NA

  Wings on fruit

  the fruit has one or more wings on it

• Glands or sap

  Sap color

  the sap is clear and watery

  Stalked glands on fruit (Rosa)

  NA

• Growth form

  Growth form

  the plant is a tree

• Leaves

  Hairs on underside of leaf blade

  the underside of the leaf has no hairs

  Hairs on upper side of leaf blade

  the upper side of the leaf is not hairy, or has very few hairs

  Leaf blade base shape

  • the base of the leaf blade is cuneate (wedge-shaped, tapers to the base with relatively straight, converging edges), or narrow
  • the base of the leaf blade is rounded

  Leaf blade base symmetry

  the leaf blade base is symmetrical

  Leaf blade bloom

  the underside of the leaf has no noticeable bloom

  Leaf blade edges

  the edge of the leaf blade has teeth

  Leaf blade edges (Acer)

  NA

  Leaf blade flatness

  the leaf is flat (planar) at the edges

  Leaf blade hairs

  the hairs on the leaf blade are different from the choices given

  Leaf blade scales

  there are no scales on the leaf blades

  Leaf blade shape

  • the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
  • the leaf blade is oblong (rectangular but with rounded ends)

  Leaf blade texture

  the leaf blade is herbaceous (has a leafy texture)

  Leaf blade translucent dots

  there are no translucent dots on the leaf blade

  Leaf blade vein pattern

  the main veins of the leaf blade are pinnate (the secondary veins branch off at intervals from the main central vein) and non-arcuate (not arched towards the leaf tip)

  Leaf blade veins

  the leaf blade has one main vein running from the base toward the tip

  Leaf duration

  the leaves drop off in winter (or they wither but persist on the plant)

  Leaf form

  the plant is broad-leaved (with broadly flattened leaf blades)

  Leaf lobe tips (Quercus)

  NA

  Leaf midrib glands

  the midrib of the leaf blade lacks glands on the upper surface

  Leaf stalk

  the leaves have leaf stalks

  Leaf stalk attachment to leaf

  the petiole attaches at the basal margin of the leaf blade

  Leaf stalk nectaries

  there are no nectaries on the leaf stalk

  Leaf teeth

  the leaf blade margin is serrate (with forward-pointing) or dentate (with outward-pointing) with medium-sized to coarse teeth

  Leaf teeth hairs (Carya)

  NA

  Leaf type

  the leaf blade is compound (i.e., made up of two or more discrete leaflets

  Leaves per node

  there are two leaves per node along the stem

  Specific leaf type

  the leaf is compound, with a single terminal leaflet and more than two additional leaflets

  Stipules

  there are no stipules on the plant, or they fall off as the leaf expands

• Place

  Habitat

  wetlands

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont

  Specific habitat

  • forests
  • river or stream floodplains
  • swamps

• Scent

  Plant odor

  the plant does not have much of an odor, or it has an unpleasant or repellant odor

• Stem, shoot, branch

  Aerial roots

  the plant has no aerial roots

  Bark texture

  the bark of an adult plant is ridged or plated

  Branch brittleness (willows only)

  NA

  Branch cross-section

  the branch is circular in cross-section, or it has five or more sides, so that there are no sharp angles

  First-year cane (Rubus)

  NA

  Lenticels on twigs

  there are clearly lenticels on the twigs

  Pith shape

  the outline of the pith in a twig is roughly round

  Short shoots

  there are no peg- or knob-like shoots present

  Twig bloom

  there is no bloom on the twig

  Twig hairs

  the twigs have few or no hairs on them

  Twig papillae (Vaccinium species only)

  NA

  Twig scales

  there are no scales on the twig surface

  Twig winter color

  • green
  • white

  Wings on branch

  the branch does not have wings on it

  armature on plant

  the plant does not have spines, prickles, or thorns

Wetland status

Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae