Rhamnus arguta

Maximowicz

Mém. Acad. Imp. Sci. Saint Pétersbourg, Sér. 7, 10(11): 6, figs. 48–51. 1866.

Common names: Saw-tooth buckthorn
Introduced
Treatment appears in FNA Volume 12. Treatment on page 51. Mentioned on page 46, 52.

Shrubs or small trees, 2–3 m, usually unarmed, rarely armed with weak thorns. Branchlets dark purple or purple-red, glabrous. Leaves deciduous, usually opposite to subopposite, sometimes alternate, usually fascicled on short-shoots, separating with age; petiole 10–28 mm; blade green abaxially, darker green adaxially, usually broadly ovate, ovate, oblong-ovate, or ovate-cordate, sometimes ovate-orbiculate, 2.5–6 (–7) cm, herbaceous, base truncate to cordate, margins spinulose-serrate, apex obtuse-rounded or acute, both surfaces glabrous or abaxial puberulent along veins; secondary-veins (3–) 4–5 pairs, all diverging at nearly same angle or proximal diverging more obtusely. Inflorescences fascicles or flowers solitary. Pedicels 10–24 (–30) mm. Sepals 4. Petals 4. Drupes black, globose to obovoid-globose, 7–10 mm; stones 3.2n = 24.


Phenology: Flowering May–Jun.
Habitat: Disturbed sites.
Elevation: 200 m.

Distribution

V12 1-distribution-map.jpg

Introduced; Ind., Asia (China)

Discussion

The only report of Rhamnus arguta as naturalized in North America is from Jasper County (F. Swink and G. Wilhelm 1994). It was identified by Swink and Wilhelm as R. arguta var. velutina Handel-Mazzetti, which is puberulent on the petioles and leaf blades (at least abaxially on veins), but considerable populational variability apparently exists within the species.

Selected References

None.

Lower Taxa

None.

"thin" is not a number.

... more about "Rhamnus arguta"
perigynous +  and epigynous +
acute +  and obtuse-rounded +
Guy L. Nesom +  and John O. Sawyer† +
Maximowicz +
truncate +  and cordate +
6 cm60 mm <br />0.06 m <br /> (7 cm70 mm <br />0.07 m <br />) +
darker green +  and green +
3[-5]-veined +  and pinnate +
spinulose +, spinose +, serrate +  and entire +
denticulate +, dentate +, crenulate +, crenate +  and serrulate +
ovate-orbiculate;ovate-cordate;oblong-ovate;ovate-cordate;oblong-ovate;ovate;ovate +
2.5 cm25 mm <br />0.025 m <br /> (6 cm60 mm <br />0.06 m <br />) +
Saw-tooth buckthorn +
Ind. +  and Asia (China) +
globose +  and obovoid-globose +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
200 m. +
bisexual +  and unisexual +
Disturbed sites. +
circumscissile +
free +  and adnate +
campanulate +  and cupulate +
unisexual +  and bisexual +
separating +, alternate +, opposite +  and subopposite +
deciduous +
intrastaminal +
2.4 cm24 mm <br />0.024 m <br /> (3 cm30 mm <br />0.03 m <br />) +
1 cm10 mm <br />0.01 m <br /> (2.4 cm24 mm <br />0.024 m <br />) +
not fleshy +
perigynous +  and epigynous +
yellowish +  and cream +
adnate +  and distinct +
not clawed +  and spatulate +
1 cm10 mm <br />0.01 m <br /> (2.8 cm28 mm <br />0.028 m <br />) +
Flowering May–Jun. +
2-4-carpellate +
Mém. Acad. Imp. Sci. Saint Pétersbourg, Sér. +
oblong-obovoid +  and obovoid +
greenish white +  and white +
distinct +
crested;not keeled;ovate-triangular +
opposite +  and subopposite +
Introduced +
4 +  and 5 +
2 +  and 4 +
Rhamnus arguta +
species +
armed +  and unarmed +
deciduous +  and evergreen +
tree +  and shrub +
spreading +  and erect +
polygamous +, dioecious +  and synoecious +