Rhamnus davurica subsp. davurica

IntroducedIllustrated
Treatment appears in FNA Volume 12. Treatment on page 50. Mentioned on page 51.

Shrubs or small trees, 2–10 m, armed with thorns. Branchlets brown or redbrown, glabrous. Leaves deciduous, opposite or sometimes fascicled on short-shoots; petiole 5–25 mm; blade green abaxially, darker green adaxially, usually oblong-obovate, sometimes broadly elliptic or ovate to obovate, rarely oblanceolate-elliptic, (4–) 5–10 (–13) cm, usually 2–3 times longer than wide, herbaceous, base cuneate, margins crenulate, apex usually acute or shortly acuminate to acuminate, rarely obtuse or rounded, abaxial surface sparsely pilose on veins, hairs straight, colorless, adaxial surface glabrous or sparsely pilose on veins; secondary-veins 3–5 (–6) pairs, all diverging at nearly same angle. Inflorescences fascicles or flowers solitary. Pedicels 10–20 mm. Sepals 4. Petals 4. Drupes black, globose, 5–6 mm; stones 2.2n = 24.


Phenology: Flowering Apr–Jun.
Habitat: Floodplains, forest edges and openings, stream banks, suburban woodlands.
Elevation: 50–300 m.

Distribution

V12 737-distribution-map.jpg

Introduced; Conn., Del., Ill., Iowa, Ky., Md., Mich., Mo., Nebr., N.J., N.Y., N.C., N.Dak., Ohio, Pa., R.I., S.Dak., Tenn., Va., Asia (China), Asia (Korea), Asia (Mongolia), Asia (Russia)

Discussion

Plants of Rhamnus davurica from the flora area have sometimes been identified as subsp. nipponica (Makino) Kartesz & Gandhi [R. davurica var. nipponica Makino, R. nipponica (Makino) Grubov; the type from Japan] (for example, D. W. Magee and H. E. Ahles 1999), but it is not clear whether they are correctly identified or even whether they are outside the range of variability in subsp. davurica.

These plants sometimes have been called Rhamnus citrifolia (Weston) W. J. Hess & Stern, an illegitimate later homonym of Rhamnus citrifolia Rusby 1907.

Selected References

None.

Lower Taxa

None.

"thin" is not a number.

pilose +  and glabrous +
perigynous +  and epigynous +
shortly acuminate +  and acuminate rarely obtuse or rounded +
Guy L. Nesom +  and John O. Sawyer† +
Pallas +
cuneate +
oblanceolate-elliptic +
10 cm100 mm <br />0.1 m <br /> (13 cm130 mm <br />0.13 m <br />) +
darker green +  and green +
3[-5]-veined +  and pinnate +
spinulose +, spinose +, serrate +  and entire +
denticulate +, dentate +, crenulate +, crenate +  and serrulate +
ovate;obovate +
5 cm50 mm <br />0.05 m <br /> (10 cm100 mm <br />0.1 m <br />) +
Conn. +, Del. +, Ill. +, Iowa +, Ky. +, Md. +, Mich. +, Mo. +, Nebr. +, N.J. +, N.Y. +, N.C. +, N.Dak. +, Ohio +, Pa. +, R.I. +, S.Dak. +, Tenn. +, Va. +, Asia (China) +, Asia (Korea) +, Asia (Mongolia) +  and Asia (Russia) +
globose +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
50–300 m. +
bisexual +  and unisexual +
Floodplains, forest edges and openings, stream banks, suburban woodlands. +
straight +
circumscissile +
free +  and adnate +
campanulate +  and cupulate +
unisexual +  and bisexual +
deciduous +
crenulate +
intrastaminal +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
not fleshy +
perigynous +  and epigynous +
yellowish +  and cream +
adnate +  and distinct +
not clawed +  and spatulate +
0.5 cm5 mm <br />0.005 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
Flowering Apr–Jun. +
2-4-carpellate +
Reise Russ. Reich. +
oblong-obovoid +  and obovoid +
greenish white +  and white +
distinct +
crested;not keeled;ovate-triangular +
opposite +  and subopposite +
Introduced +  and Illustrated +
4 +  and 5 +
2 +  and 4 +
Rhamnus davurica subsp. davurica +
Rhamnus davurica +
subspecies +
deciduous +  and evergreen +
tree +  and shrub +
spreading +  and erect +
polygamous +, dioecious +  and synoecious +