Ulmus thomasii — rock elm

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

  Bud scar shape (Fraxinus)

  NA

  Collateral buds

  there are no collateral buds on the sides of the branches

  Leaf scar arrangement

  there is one leaf scar per node on the stem or twig

  Superposed buds

  there are no superposed buds on the branch

• Flowers

  Carpels fused

  the carpels are fused to one another

  Enlarged sterile flowers

  there are no enlarged sterile flowers on the plant

  Flower appearance

  the flowers appear before the leaves

  Flower petal color

  • purple
  • yellow or green

  Flower symmetry

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

  Hairs on ovary (Amelanchier)

  NA

  Inflorescence position

  the inflorescences grow on older branches

  Inflorescence type

  • the inflorescence is a monochasial cyme (an axis with a terminal flower, below it a branch with a terminal flower, this branch may itself have a branch and so on)
  • the inflorescence is a raceme (a long unbranched stem with stalked flowers growing along it)

  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

  the petals are thin and delicate, and pigmented (colored other than green or brown)

  Petal fusion

  the perianth parts are fused to form a tube, cup, or bell shape

  Sepal appearance

  the sepals resemble petals in color and texture

  Sepal cilia (Ilex)

  NA

  Sepals fused only to sepals

  the sepals are fused to each other (not other flower parts), at least near their bases

  Stamen number

  • 5
  • 6
  • 7
  • 8

  Stamen position relative to petals

  the stamens are lined up with the sepals (antesepalous)

  Stamens fused

  the stamens are not fused to one another

• 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 fuzzy or hairy
  • 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 rounded

  Leaf blade base symmetry

  • the leaf blade base is asymmetrical
  • the leaf blade base is symmetrical

  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 length

  25–160 mm

  Leaf blade scales

  there are no scales on the leaf blades

  Leaf blade shape

  • the leaf blade is elliptic (widest near the middle and tapering at both ends)
  • the leaf blade is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
  • the leaf blade is ovate (widest below the middle and broadly tapering at both ends)

  Leaf blade texture

  • the leaf blade is chartaceous (thin and dry like paper)
  • the leaf blade is herbaceous (has a leafy texture)

  Leaf blade translucent dots

  there are no translucent dots on the leaf blade

  Leaf blade width

  25–50 mm

  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 nectaries

  there are no nectaries on the leaf stalk

  Leaf teeth

  the leaf blade margin has teeth, which themselves have smaller teeth on them

  Leaf teeth hairs (Carya)

  NA

  Leaf type

  the leaf blade is simple (lobed or unlobed but not separated into leaflets)

  Leaves per node

  there is one leaf per node along the stem

  Specific leaf type

  the leaves are simple (lobed or unlobed but not separated into leaflets

• Place

  Habitat

  terrestrial

  New England state

  • New Hampshire
  • Vermont

  Specific habitat

  • forests
  • ridges or ledges
  • river or stream floodplains
  • swamps
  • woodlands

• 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

  First-year cane (Rubus)

  NA

  Twig papillae (Vaccinium species only)

  NA

  Twig winter color

  • brown
  • gray
  • red

  Wings on branch

  the branch has wings running along it

  armature on plant

  the plant does not have spines, prickles, or thorns

Wetland status

Occurs in wetlands or non-wetlands. (Wetland indicator code: FAC)

In New England

From Flora Novae Angliae dichotomous key