Crataegus douglasii |
Crataegus teres |
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black hawthorn, Douglas' hawthorn |
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Habit | Shrubs, 40–80 dm. | Shrubs or trees, 30–60 dm, branches ± weeping. |
Stems | 1-year old twigs deep tan to dark mahogany, ± shiny young, older gray to dark gray, often showing brown or alternatively tan-brown eastward; thorns on twigs straight or slightly recurved, deep brown young, (1.5–)2–3.5 cm. |
twigs slightly flexuous, new growth glabrate, 1-year old tawny to reddish brown, 2-years old dark gray; thorns on twigs ± straight, 2-years old shiny blackish gray, ± fine to ± stout, 2–3 cm. |
Leaves | petiole 0.7–1.5 cm, pubescent young, slightly glandular; blade usually elliptic to broadly elliptic or subrhombic (elliptic-obovate when lobes very small), 4–7 cm, lobes 2–4 per side, sinuses shallow, LII 10–20%, lobe apex subobtuse to acute, margins coarsely, sharply serrate, teeth small, gland-tipped young, venation craspedodromous, veins 4 or 5 per side, apex acute to obtuse, abaxial surface usually glabrous except on veins, adaxial densely short-appressed-pubescent. |
petiole length 15–20% blade, ± pilose young, glandular; blade dark green mature adaxially, narrowly obovate, 2–3.5 cm, thin, slightly coriaceous, base ± evenly tapered, lobes 0, margins finely glandular-serrate, veins (2 or)3 or 4 per side, apex flat-triangular to rounded or ± truncate, often minutely cuspidate, adaxially shiny mature, abaxial surface glabrous, adaxial veins sparsely hairy; on extension shoots broadly elliptic to suborbiculate, larger, often slightly incised, strongly serrate. |
Inflorescences | 10–25-flowered; branches glabrous; bracteole margins stipitate- or sessile-glandular. |
2–6-flowered; branches glabrate; bracteoles linear, margins glandular. |
Flowers | 10–15 mm diam.; hypanthium glabrous; sepals broadly triangular, 3–4 mm, margins sparsely glandular, adaxially glabrous; stamens 10, anthers pink; styles 3 or 4. |
16 mm diam.; hypanthium glabrous; sepals narrowly triangular, 4–5 mm, margins glandular-serrate, adaxially sparsely hirsute; anthers pale yellow; styles 2 or 3. |
Pomes | vinous and usually waxy glaucous young, dull black mature, usually ellipsoid, 6–8 mm diam., glabrous; sepal remnants reflexed, apex obtuse; pyrenes 3 or 4, sides excavated, sometimes only shallowly. |
red, ± ellipsoid, 8–10 mm diam., glabrous; sepals spreading, 7 mm; pyrenes 2 or 3. |
2n | = 68. |
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Crataegus douglasii |
Crataegus teres |
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Phenology | Flowering May–Jun; fruiting Sep–Oct. | Flowering Mar; fruiting Aug–Sep. |
Habitat | Brush, old fields, fencerows, woodland edges | Pine woods, sandy fields |
Elevation | 50–1600 m (200–5200 ft) | 0–100 m (0–300 ft) |
Distribution |
AK; CA; ID; MI; MN; MT; OR; WA; WI; AB; BC; ON; SK
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AL |
Discussion | Crataegus douglasii occurs from southern and western British Columbia to the panhandle of Alaska and ranges to northern California and the Rocky Mountains of Idaho, Montana, and southwestern Alberta. Disjunct populations occur farther east in the Cypress Hills (Alberta and Saskatchewan), the Montana montane islands, and around the northern Great Lakes. In western North America, C. douglasii is found mainly near water in drier areas; in more mesic regions, it may occur in open woodlands. In the Great Lakes area, it mainly occurs in old pastures and on fencerows. Crataegus douglasii is distinguished from C. gaylussacia by having ten stamens and is rather variable in leaf shape and size. The species is distinguished from C. okennonii by the latter usually being taller and typically more erect as well as having a usually straight, single trunk, shorter thorns, ampulliform-orbicular fruit, and often purplish crimson fall foliage. Crataegus castlegarensis is the most similar species, and beyond possessing relatively few to many multiple thorns, it is distinguished from C. douglasii by its hairy hypanthia, pedicels, and, often, fruit, which is orbicular, plump, crimson to purple in late August, ripening to deep purple (sometimes black) at a time when sympatric C. douglasii is fully black. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Crataegus teres, C. attrita, and C. florens appear to form a natural group and may be difficult to distinguish. They share more or less unlobed, rather narrow, subcoriaceous, bright to deep green leaves with more or less sharply denticulate margins, subglabrous herbage, and inflorescence branches subglabrous to pilose, lacking the dense tomentum characteristic of many members of ser. Lacrimatae. They are not part of the C. alabamensis complex. Crataegus teres, the least common of the three, has perhaps the most individual characteristics, including manifesting a merely slightly flexuous twig, having the smoothest leaf tips, and with C. florens, the most venous leaves (usually 3–4 per side), also subglabrous or pilose inflorescence branches, and 2 or 3 styles, an ensemble of characteristics not unlike what might be found in ser. Crus-galli. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 512. | FNA vol. 9, p. 628. |
Parent taxa | Rosaceae > subfam. Amygdaloideae > tribe Maleae > Crataegus > sect. Douglasia > ser. Douglasianae | Rosaceae > subfam. Amygdaloideae > tribe Maleae > Crataegus > sect. Coccineae > ser. Lacrimatae |
Sibling taxa | ||
Synonyms | C. columbiana, C. tennowana | C. alabamensis var. teres |
Name authority | Lindley: Edwards's Bot. Reg. 21: plate 1810. (1835) | Beadle: Biltmore Bot. Stud. 1: 43. (1901) |
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