Crataegus douglasii |
Crataegus stonei |
|
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black hawthorn, Douglas' hawthorn |
Stone's hawthorn |
|
Habit | Shrubs, 40–80 dm. | Shrubs, 10–20 dm. |
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: new growth reddish green, glabrous or villous, 1-year old dull reddish brown, eventually gray; thorns on twigs ± straight, 2-years old blackish, ultimately gray, ± slender, 4–6 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 30–40% blade, winged distally, villous, glandular; blade narrowly ovate, 7–8 cm, base cuneate, lobes 0 or 1–3 per side, sinuses shallow, lobe apex acute, margins serrate, teeth gland-tipped, veins 4 or 5 per side, apex acuminate, abaxial surface sparsely villous along veins, adaxial sparsely villous. |
Inflorescences | 10–25-flowered; branches glabrous; bracteole margins stipitate- or sessile-glandular. |
4–6-flowered; branches villous; bracteoles not seen. |
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. |
18–20 mm diam.; hypanthium densely pubescent; sepal length not recorded, margins coarsely glandular-serrate, acuminate, abaxially pubescent; stamens 5–10, anthers pink; styles 3 or 4. |
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. |
dull yellow to russet, broadly ellipsoid, 12–14 mm diam., hairy; sepals on collar, ± reflexed; pyrenes 3 or 4. |
2n | = 68. |
|
Crataegus douglasii |
Crataegus stonei |
|
Phenology | Flowering May–Jun; fruiting Sep–Oct. | Flowering late May–early Jun; fruiting Sep–Oct. |
Habitat | Brush, old fields, fencerows, woodland edges | Woods, openings |
Elevation | 50–1600 m (200–5200 ft) | 20–300 m (100–1000 ft) |
Distribution |
AK; CA; ID; MI; MN; MT; OR; WA; WI; AB; BC; ON; SK
|
MA; NY; PA |
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.) |
Of conservation concern. Crataegus stonei is another species related to C. biltmoreana, from which it differs mainly in its pink anthers, proportionately narrower and more elongate leaves, and lower stature. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 512. | FNA vol. 9, p. 591. |
Parent taxa | Rosaceae > subfam. Amygdaloideae > tribe Maleae > Crataegus > sect. Douglasia > ser. Douglasianae | Rosaceae > subfam. Amygdaloideae > tribe Maleae > Crataegus > sect. Coccineae > ser. Intricatae |
Sibling taxa | ||
Synonyms | C. columbiana, C. tennowana | C. biltmoreana var. stonei |
Name authority | Lindley: Edwards's Bot. Reg. 21: plate 1810. (1835) | Sargent: Rhodora 5: 62. (1903) |
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