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• Quercus phellos

Quercus phellos — willow oak

Facts

Willow oak is so named for its long, narrow, willow-like leaves. It resembles laurel oak (Q. imbricaria) in being one of only two oak species in our area with long, unlobed leaves, but willow oak leaves are narrower and the acorns are smaller than those of Q. imbricaria. The acorns are an important source of food for mammals. The heart of this species' range is in the southeast, where it typically inhabits bottomlands; thus, it grows well and rapidly in wetter soils and moist parts of the garden. Willow oak ventures into New England only in southern Connecticut.

Habitat

Anthropogenic (man-made or disturbed habitats), forest edges, forests

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

  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 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 inflorescence has only one flower on it
  • the inflorescence is an ament (catkin; slender, usually pendulous inflorescence with crowded unisexual flowers)

  Number of pistils

  1

  Ovary position

  the ovary is below 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
  • 10
  • 11
  • 12
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9

• Fruits or seeds

  Berry color

  NA

  Fruit tissue origin

  there are no flower parts that form part of the fruit

  Fruit type (general)

  the fruit is dry but does not split open when ripe

  Fruit type (specific)

  the fruit is a nut (dry and indehiscent, with a hard wall, usually containing only one seed and usually subtended by an involucre)

  Wings on fruit

  there are no wings on the fruit

• 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 shrub (i.e., a woody plant with several stems growing from the base)
  • 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 no teeth or lobes

  Leaf blade edges (Acer)

  NA

  Leaf blade flatness

  the leaf is flat (planar) at the edges

  Leaf blade hairs

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

  Leaf blade length

  50–120 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 linear (very narrow with more or less parallel sides)

  Leaf blade texture

  the leaf blade is coriaceous (has a firm, leathery texture)

  Leaf blade translucent dots

  there are no translucent dots on the leaf blade

  Leaf blade width

  10–25 mm

  Leaf duration

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

  Leaf lobe tips (Quercus)

  • NA
  • the lobes of the leaf blade are tipped with small bristles

  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 edge of the leaf blade is entire (has no teeth or lobes)

  Leaf teeth hairs (Carya)

  NA

  Leaf type

  the leaf blade is simple (i.e., 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 (i.e., lobed or unlobed but not separated into leaflets

• Place

  Habitat

  terrestrial

  New England state

  Connecticut

  Specific habitat

  • edges of forests
  • forests
  • 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

  Pith shape

  the ouline of the pith in a twig is roughly star-shaped, with several points or arms radiating from the center

  Twig papillae (Vaccinium species only)

  NA

  Twig winter color

  • brown
  • orange
  • red

  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