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• Oleaceae
• Fraxinus
• Fraxinus excelsior

Fraxinus excelsior — European ash

Facts

European ash is not especially widespread in North America, but it is a common and iconic tree of European forests. Its wood is flexible and valued for producing furniture, oars, and handles; it also burns well even when green. The leaves exude tannins and substances used to make a green dye. In the 1990s a fungus (Hymenoscyphus pseudoalbidus) began to decimate stands of this valuable, drought-tolerant, fast-growing tree in Poland, and the pathogen has killed many trees throughout Europe. Intensive research is underway to identify resistant trees.

Habitat

Anthropogenic (man-made or disturbed habitats)

Characteristics

• Buds or leaf scars

  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

  Collateral buds

  there are no collateral buds on the sides of the branches

  Superposed buds

  there are no superposed buds on the branch

• Flowers

  Anther color

  there is a noticeable pink, reddish or purplish tint to the anthers

  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 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 cilia (Ilex)

  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 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

  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)
  • the leaf blade is ovate (widest below the middle and broadly tapering at both ends)

  Leaf blade texture

  the leaf blade is herbaceous (has a leafy texture)

  Leaf duration

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

  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 no leaf stalks, but attach directly to the stem

  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

• Place

  Habitat

  terrestrial

  New England state

  • Connecticut
  • Massachusetts

  Specific habitat

  man-made or disturbed habitats

• 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
  • the bark of an adult plant is thin and smooth

  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

  Twig papillae (Vaccinium species only)

  NA

  Twig winter color

  • brown
  • gray

  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

Not classified

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae