OregonFlora: Quercus coccinea vs. Quercus

	Quercus coccinea	Quercus
		oak
Habit		Trees or shrubs evergreen or deciduous; bark split into parallel ridges or loose plates or strips.
Leaves		thick and leathery or thin and flexible; margins entire, toothed, crenate, or lobed; secondary veins reaching margins or turning aside; surfaces abaxially glabrous or with appressed yellow hairs.
Inflorescences		unisexual, staminate catkins flaccid, usually pendent, elongate spikes, pistillate flowers 1–few.
Fruits		(acorns) 1 per cup; round in cross section, ripening 1st or 2nd year after flowering; cups undivided, enclosing only lower part of fruits, scaly; scales appressed or slightly spreading, overlapping and covering surface of cups, 2–7 mm.

	Quercus coccinea	Quercus
Distribution	[WildflowerSearch map] [BONAP county map]	[BONAP county map]
Discussion		Temperate area and tropical mountains of Northern Hemisphere. ~400 species; 5 treated in Flora. Several exotic species of oak are widely planted as shade trees, and seedlings of two of these species are sometimes found in the vicinity of cultivated trees. Red oak (Quercus rubra), of the eastern United States, will key to Q. kelloggii. It can be recognized by having completely glabrous leaves except for small tufts of hairs in the vein axils on the leaf underside and the upper leaf surface is dull. Additionally, its cups are saucer-shaped and cover only ? or less of the nuts, and its scales are distinctly convex-thickened at their bases. English oak (Q. robur) will key to Q. garryana, but it can be recognized by short (2–8 mm) petioles, narrowly auriculate leaf bases, and fruits on peduncles that are 2–8 cm.
Source		Flora of Oregon, volume 2, page 747 Alan Whittemore
Sibling taxa	Q. chrysolepis, Q. garryana, Q. kelloggii, Q. palustris, Q. robur, Q. rubra, Q. sadleriana, Q. vacciniifolia
Subordinate taxa		Q. chrysolepis, Q. garryana, Q. kelloggii, Q. palustris, Q. robur, Q. rubra, Q. sadleriana, Q. vacciniifolia
Web links	Local Web sites: Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Quercus coccinea

Quercus

oak

Habit

Trees or shrubs evergreen or deciduous; bark split into parallel ridges or loose plates or strips.

Leaves

thick and leathery or thin and flexible;

margins entire, toothed, crenate, or lobed;

secondary veins reaching margins or turning aside;

surfaces abaxially glabrous or with appressed yellow hairs.

Inflorescences

unisexual, staminate catkins flaccid, usually pendent, elongate spikes, pistillate flowers 1–few.

Fruits

(acorns) 1 per cup; round in cross section, ripening 1st or 2nd year after flowering; cups undivided, enclosing only lower part of fruits, scaly;

scales appressed or slightly spreading, overlapping and covering surface of cups, 2–7 mm.

Quercus coccinea

Quercus

Distribution

[WildflowerSearch map]

[BONAP county map]

Discussion

Temperate area and tropical mountains of Northern Hemisphere. ~400 species; 5 treated in Flora.

Several exotic species of oak are widely planted as shade trees, and seedlings of two of these species are sometimes found in the vicinity of cultivated trees. Red oak (Quercus rubra), of the eastern United States, will key to Q. kelloggii. It can be recognized by having completely glabrous leaves except for small tufts of hairs in the vein axils on the leaf underside and the upper leaf surface is dull. Additionally, its cups are saucer-shaped and cover only ? or less of the nuts, and its scales are distinctly convex-thickened at their bases. English oak (Q. robur) will key to Q. garryana, but it can be recognized by short (2–8 mm) petioles, narrowly auriculate leaf bases, and fruits on peduncles that are 2–8 cm.

Source

Flora of Oregon, volume 2, page 747
Alan Whittemore

Sibling taxa