Rosa minutifolia

Engelmann

Bull. Torrey Bot. Club 9: 97. 1882.

Common names: Ensenada or small-leaved rose
Conservation concernIllustrated
Synonyms: Hesperhodos minutifolius (Engelmann) Hurst
Treatment appears in FNA Volume 9. Treatment on page 79.

Shrubs forming dense, low thickets. Stems usually erect, (3–) 5–12 (–15) dm; distal branches pubescent or glabrous, without stellate hairs; infrastipular prickles absent, internodal prickles sparse to common, erect, (2–) 6–10 (–12) × 1–3 mm, pubescent at least basally, mixed with dense aciculi, to 3 mm. Leaves 1.5–2.5 cm; stipules 3.5–4 × 1.5–2 mm, margins entire or dentate with glands, surfaces pubescent, eglandular, auricles acute, (0.5–) 2–3 mm, surfaces pubescent, eglandular; petiole and rachis puberulent, stipitate-glands and pricklets sparse; leaflets 5–7, terminal: petiolule 1–4 mm, blade oval, suborbiculate, or obovate, 3–7 × 2–6 mm, margins deeply 1- or multilobed, usually glandular, teeth lobelike, (3 or) 4 or 5 (or 6) per side on distal 1/2 of blades, some multi-serrate, apex acute to obtuse, abaxial surfaces pubescent (especially on veins), adaxial dull, sometimes pubescent. Inflorescences 1 (–3) -flowered. Pedicels 2–9 mm, setae sparse, eglandular; bracts 1 or 2. Flowers 2.5–3 cm diam.; hypanthium subglobose to globose, 3–4 × 2.5–3.5 mm, densely pubescent and setose; sepals spreading, 8–12 × 2–4 mm, tip 4–6 × 1–1.5 mm, lobes 3–4, margins usually gland-tipped, abaxial surfaces pubescent, setae sparse, eglandular or sparsely glandular; petals usually pink to light rose-pink, sometimes white, 10–15 (–20) × 9–14 mm; stamens 45; carpels 10–25 (–30), styles exsert 1–2 mm beyond stylar orifice (2–4 mm diam.), rims 0.5–0.8 mm wide. Hips dark reddish purple, subglobose, 5–7 × 5–7 mm, setae 1–4 mm, pubescent, eglandular. Achenes 6–16, dark, ± terete-elongate, 3.5–4 × 1.5–2 mm. 2n = 14.


Phenology: Flowering Mar–Jul.
Habitat: Dry washes, brush, grasslands, sagebrush, rocky hillsides
Elevation: 0–200 m

Distribution

V9 115-distribution-map.jpg

Calif., Mexico (Baja California)

Discussion

Of conservation concern.

Rosa minutifolia was first collected in the United States in 1985 (San Diego County; G. A. Levin 1986). Before being extirpated by a development project, the single population was re-established in a nearby protected site, where the transplants are reportedly doing well (C. Burrascano, pers. comm.). Existence of R. minutifolia in the United States remains of conservation concern. Although common where found in coastal scrub of Baja California, Mexico, the habitat there is considered threatened by development.

Selected References

None.

Lower Taxa

None.

"dm" is not declared as a valid unit of measurement for this property.

... more about "Rosa minutifolia"
eglandular +  and sessile +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
terete-elongate +
1.5mm +  and 2mm +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
Walter H. Lewis +, Barbara Ertter +  and Anne Bruneau +
Engelmann +
gray +, red +  and brown +
exfoliating +
compound +  and simple +
opposite +  and alternate +
cuneate +
Undefined subg. Hesperhodos +
0.3 cm3 mm <br />0.003 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
lustrous +  and dull +
smooth +  and rugose +
obovate +, suborbiculate +  and oval +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
? (?) +  and ? (?) +
2mm +  and 6mm +
free +  and distinct +
Ensenada or small-leaved rose +
glabrous +  and pubescent +
Calif. +  and Mexico (Baja California) +
not +  and aggregated +
0–200 m +
2.5 cm25 mm <br />0.025 m <br /> (3 cm30 mm <br />0.03 m <br />) +
2.5 cm25 mm <br />0.025 m <br /> (5 cm50 mm <br />0.05 m <br />) +
not +  and aggregated +
eglandular +  and glandular +
urceolate +, pyriform +, oblong +, ellipsoid +, ovoid-obovoid +  and globose +
Dry washes, brush, grasslands, sagebrush, rocky hillsides +
1.3 cm13 mm <br />0.013 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
1.6 cm16 mm <br />0.016 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
dark reddish +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
stipitate-glandular +, setose +, glabrous +  and pubescent +
subglobose +
leathery +  and hard +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
purplish black +, purplish red +, orange-red +  and red +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
setose +  and pubescent +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
leathery +  and fleshy +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
crassinucellate +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0 cm0 mm <br />0 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
3-foliate +  and compound +
deciduous +
1.5cm +  and 3cm +
1.5 cm15 mm <br />0.015 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
petiolulate +  and subsessile +
elliptic +  and obovate more or less oblong obovate-elliptic lanceolate-elliptic or obovate-oblong +
1-or-multilobed +, dentate +  and entire +
pinnatifid +, serrate +  and deeply incised +
distinct +
inferior +  and superior +
clustered +, biseriate +  and superposed +
glabrous +, pubescent +  and setose +
0.2 cm2 mm <br />0.002 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
free +  and distinct +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.9 cm9 mm <br />0.009 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Flowering Mar–Jul. +
adnate +, free +, connate +  and distinct +
Bull. Torrey Bot. Club +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
not arillate +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
persistent +
free +  and distinct +
ovatelanceolate +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
eglandular +  and glandular +
0.1 cm1 mm <br />0.001 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
rarely densely puberulent +  and tomentose +
Conservation concern +  and Illustrated +
free +  and distinct +
branched +  and simple +
procumbent +  and climbing +
1 +  and 20 +
caducous +  and persistent +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
eglandular +, glandular +  and dentate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
persistent +
not elongate +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Hesperhodos minutifolius +
Rosa minutifolia +
Rosa sect. Minutifoliae +
species +
4mm +  and 6mm +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
5 +  and 4 +
inconspicuous +
enlarged +  and small +