Prunus maritima |
Prunus gracilis |
|
---|---|---|
beach plum |
Oklahoma plum, Oklahoma plume |
|
Habit | Shrubs, suckering, 10–25 dm, not thorny. | Shrubs, suckering, 3–15 dm, not thorny. |
Twigs | with axillary end buds, densely hairy to glabrate. |
with axillary end buds, densely hairy. |
Leaves | deciduous; petiole 3–11 mm, usually densely hairy, rarely hairy only on adaxial surface, usually eglandular, sometimes glandular distally, glands 1–2, discoid; blade elliptic, broadly elliptic, or obovate (orbiculate in gravesii clone), 3.5–7 × 2–4 cm, base cuneate to obtuse (rounded in gravesii clone), margins finely, usually singly, rarely doubly, serrulate, teeth sharp, usually eglandular, rarely glandular, apex acute to obtuse (rounded in gravesii clone), abaxial surface usually hairy, sometimes only on veins or glabrescent, adaxial rugose, glabrous. |
deciduous; petiole 3–8 mm, densely hairy, usually eglandular, sometimes glandular distally, glands 1–3, discoid; blade usually ovate or elliptic, rarely obovate, 2–5(–7) × 1–2.5(–3.6) cm, base obtuse to cuneate, margins finely, singly or doubly serrulate, teeth sharp, usually eglandular, sometimes glandular, glands blackish, spheric, apex acute to obtuse, abaxial surface densely hairy, adaxial sparsely hairy. |
Inflorescences | 2–4-flowered, umbellate fascicles. |
2–4(–6)-flowered, umbellate fascicles. |
Pedicels | 5–15 mm, hairy. |
4–15 mm, hairy. |
Flowers | blooming before leaf emergence; hypanthium campanulate, 2.5–3.5 mm, hairy externally; sepals erect to spreading, ovate, 1.5–3.5 mm, margins entire, sometimes 2-fid at apices, ciliate, surfaces hairy; petals white, oblong-obovate, 3–8 mm; ovaries glabrous. |
blooming before or at leaf emergence; hypanthium campanulate, 2–3 mm, hairy externally; sepals erect to spreading, ovate-oblong, 1.5–2.5 mm, margins usually entire, sometimes glandular-toothed or eglandular, sometimes ciliate, surfaces hairy; petals white, oblong to obovate, 4–7 mm; ovaries glabrous. |
Drupes | red, yellow, dark blue, or purplish black, glaucous, globose, 11–18 mm, glabrous; mesocarps fleshy; stones ovoid, slightly flattened. |
yellow, orange, or red, slightly glaucous, globose to ellipsoid, 9–18 mm, glabrous; mesocarps fleshy; stones subglobose to ellipsoid, ± flattened. |
2n | = 16. |
|
Prunus maritima |
Prunus gracilis |
|
Phenology | Flowering Apr–Jun; fruiting Aug–Oct. | Flowering Mar–Apr; fruiting Jun–Aug. |
Habitat | Sand dunes, beaches, sandy fields, roadsides, coastal barrens | Sandy roadsides, upland thickets, open woods, waste places |
Elevation | 0–30 m (0–100 ft) | 100–1300 m (300–4300 ft) |
Distribution |
CT; DE; MA; MD; ME; NH; NJ; NY; PA; RI; VA
|
AR; CO; KS; LA; NM; OK; TX |
Discussion | Prunus gravesii has been known from only a single locality since its description in 1897, and there may never have been more than a single, multistemmed individual. G. J. Anderson (1980) concluded that it is a mutant derivative of P. maritima. In the study by Anderson, it differed with statistical significance from other specimens of P. maritima for only 4 of 38 morphological features measured, and even for those four the range in values between the two taxa overlapped. Their leaf flavonoid chromatograms were identical. From a conservation standpoint it is of value to designate the orbiculate-leaved gravesii clone as a distinct taxonomic variety, for which the name P. maritima var. gravesii (Small) G. J. Anderson is available. Once listed by the state of Connecticut as endangered, it is now believed to be extinct in the wild. Throughout much of its original range P. maritima is threatened by oceanside development. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Typically, sepals of Prunus gracilis are eglandular; in some specimens, glands occur along the margins. Similar glands are sometimes found on the tips of teeth along the leaf margins. The teeth are always sharp-pointed rather than blunt or rounded as they are in those plums whose leaves consistently have glandular teeth. Presence of glands on the sepals is not correlated with glands on leaf marginal teeth. Prunus gracilis, native to the southern Great Plains, is very similar to P. maritima, a plum of the eastern seaboard over 1600 km away. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 380. | FNA vol. 9, p. 380. |
Parent taxa | Rosaceae > subfam. Amygdaloideae > tribe Amygdaleae > Prunus | Rosaceae > subfam. Amygdaloideae > tribe Amygdaleae > Prunus |
Sibling taxa | ||
Synonyms | P. gravesii, P. maritima var. gravesii | |
Name authority | Marshall: Arbust. Amer., 112. (1785) | Engelmann & A. Gray: Boston J. Nat. Hist. 5: 243. (1845) |
Web links |