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- Quercus stellata
Quercus stellata — post oak
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Facts
Post oak gets its common name from the use of its tough wood in making posts, railroad ties, and lumber. Its leaves are variably shaped, from deeply to barely lobed; the lobes are longest toward the front of the leaf, giving it a top-heavy look. Infusions of the astringent bark have been used by Native Americans to treat a variety of ailments, from chapped skin and sores to dysentery.
Habitat
Meadows and fields, ridges or ledges, sandplains and barrens, talus and rocky slopes, woodlands
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
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Characteristics
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Massachusetts
- Rhode Island
- Growth form
- the plant is a tree
- 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
- Leaf blade edges
- the edge of the leaf blade has lobes, or it has both teeth and lobes
- Leaf duration
- the leaves drop off in winter (or they wither but persist on the plant)
- armature on plant
- the plant does not have spines, prickles, or thorns
- Leaf blade length
- 40–200 mm
- Leaf blade width
- 20–120 mm
- Leaf stalk
- the leaves have leaf stalks
- Fruit type (general)
- the fruit is dry but does not split open when ripe
- Bark texture
- the bark of an adult plant is ridged or plated
- Twig winter color
-
- brown
- gray
- green
- yellow
- 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
-
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 tree
-
Leaves
- Hairs on upper side of leaf blade
- the upper side of the leaf is fuzzy or hairy
- Leaf blade base shape
-
- The base of the leaf blade is cordate (heart-shaped, with rounded lobes)
- the base of the leaf blade is attenuate (tapering very gradually to a prolonged tip)
- 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 edges
- the edge of the leaf blade has lobes, or it has both teeth and lobes
- Leaf blade edges (Acer)
- NA
- Leaf blade flatness
- the leaf is flat (planar) at the edges
- Leaf blade hairs
-
- at least some of the hairs on the leaf blade are branched
- at least some of the hairs on the leaf blade have glands at their tips
- Leaf blade length
- 40–200 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 obtriangular (triangular, but widening out from a narrow base to a broad, truncate tip)
- 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
- 20–120 mm
- Leaf duration
- the leaves drop off in winter (or they wither but persist on the plant)
- Leaf lobe tips (Quercus)
- the lobes of the leaf blade are rounded or bluntly pointed
- 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)
- the leaf blade margin is undulate (wavy), but does not have teeth
- 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
- Massachusetts
- Rhode Island
- Specific habitat
-
- meadows or fields
- ridges or ledges
- sandplains or barrens
- talus or rocky slopes
- 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
- 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
- gray
- green
- yellow
- 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 non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)
In New England
Distribution
- Connecticut
- present
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- present
- Vermont
- absent
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- uncommon to fairly widespread (S-rank: S3S4)
- Rhode Island
- extremely rare (S-rank: S1), concern (code: C)
From Flora Novae Angliae dichotomous key
15. Quercus stellata Wangenh. N
post oak. CT, MA, RI; coastal plain. Dry-mesic woodlands, fields, and barrens, often associated with rocky ridges and slopes.
1×15. Quercus alba × Quercus stellata → Quercus ×fernowii Trel. is a very rare oak hybrid known from MA. It displays intermediacy in leaf blade outline and pubescence and peduncle length (see identification key for details).
12×15. Quercus prinoides × Quercus stellata → Quercus ×stelloides Palmer is a very rare oak hybrid known from MA, RI. It is best diagnosed by using the leaf blades, which resemble most Q. stellata with 3 or 4 pairs of short, rounded or pointed lobes that are sometimes expanded and retuse at the apex and stellate-pubescent abaxially. It is normally a shrubby plant 1–2 m tall but sometimes grows to 4 m.
Native to North America?
Yes
Sometimes confused with
- Quercus bicolor:
- leaf blades variably lobed, but never cruciform, abaxially with both minute, stellate hairs and taller, erect, 1- to 4-rayed hairs, and peduncles mostly 40–70 mm long (vs. Q. stellata, with leaf blades often cruciform, that is with 2 larger lobes that project at +/- right angles from the midrib, abaxially with minute, stellate hairs, and peduncle mostly up to 6 mm long).