Amelanchier canadensis var. obovalis

(Michaux) Britton

Prelim. Cat., 17. 1888.

Endemic
Basionym: Mespilus canadensis var. obovalis Michaux Fl. Bor.-Amer. 1: 291. 1803
Synonyms: Amelanchier canadensis subsp. obovalis (Michaux) P. Landry
Treatment appears in FNA Volume 9. Treatment on page 659. Mentioned on page 658.

Shrubs, 0.2–2 m. Stems 1–100, forming dense colonies and often evidently stoloniferous. Leaves: blade elliptic or oval to oblong or obovate, (24–) 34–40 (–62) × (12–) 18–27 (–38) mm, base subcordate to cuneate, apex acute or obtuse and mucronate, surfaces glabrous (or sparsely hairy). Inflorescences (5–) 7–9 (–11) -flowered, usually compact, (6–) 15–27 (–45) mm. Pedicels: (0 or) 1 subtended by a leaf, proximalmost (1–) 5–10 (–15) mm. Flowers: sepals ascending or spreading after flowering, (0.8–) 1.8–2.7 (–4) mm; petals elliptic, (5–) 6–8 (–10.4) × (1.9–) 2.6–3.5 (–4.3) mm; stamens (15–) 19–21 (–28); styles (3 or) 4 or 5 (or 6). Pomes purplish black, 6–8 mm diam. 2n = 2x, 3x.


Phenology: Flowering Mar–May; fruiting May–Jun.
Habitat: Pine savannas, sandhills, roadsides, dry openings in woods, sandy soil
Elevation: 0–200 m

Distribution

V9 1133-distribution-map.jpg

Del., Ga., Md., N.J., N.C., Pa., S.C., Va.

Discussion

C. T. Frye (2006) found morphologic evidence of introgression between var. canadensis and var. obovalis; the introgression may have been facilitated by land clearing and other anthropogenic disturbances. Variety obovalis represents a geographic trend towards smaller petal and inflorescence dimensions in the southern range; there is much overlap range-wide. Additionally, characters such as plant height and extent of lateral spread that have been used in major couplets of keys are variable and may largely depend on site disturbance history, for example, mowing, burning. Variety obovalis is self-incompatible and apparently sexual (C. T. Frye, unpubl.) and diploid throughout its range (M. B. Burgess et al., unpubl.). The triploid count (2n = 51) is represented by a single specimen determined by W. A. Robinson and C. R. Partenen (1980).

Selected References

None.

Lower Taxa

None.
hairy +, glabrous +, glabrous or +  and sparsely moderately hairy +
1 cm10 mm <br />0.01 m <br /> (5.5 cm55 mm <br />0.055 m <br />) +
glabrous +  and hairy +
Christopher S. Campbell +, Michael B. Burgess +, Kevin R. Cushman +, Eric T. Doucette +, Alison C. Dibble +  and Christopher T. Frye +
(Michaux) Britton +
fissuring in older trees +  and smooth +
salmon colored +, brown +  and gray +
compound +  and simple +
opposite +  and alternate +
subcordate +  and cuneate +
Mespilus canadensis var. obovalis +
4 cm40 mm <br />0.04 m <br /> (6.2 cm62 mm <br />0.062 m <br />) +
2.7 cm27 mm <br />0.027 m <br /> (3.8 cm38 mm <br />0.038 m <br />) +
3.4 cm34 mm <br />0.034 m <br /> (4 cm40 mm <br />0.04 m <br />) +
oval +  and oblong or obovate +
? (?) +  and ? (?) +
18mm +  and 27mm +
adnate +  and connate +
Del. +, Ga. +, Md. +, N.J. +, N.C. +, Pa. +, S.C. +  and Va. +
not +  and aggregated +
0–200 m +
unisexual +  and bisexual +
not +  and aggregated +
not +  and aggregated +
purplish +  and nearly black pinkish or maroon-purple dark purple-blue or brownish +
0.6 cm6 mm <br />0.006 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Pine savannas, sandhills, roadsides, dry openings in woods, sandy soil +
glabrous +  and hairy +
(5-)7-9(-11)-flowered +
2.7 cm27 mm <br />0.027 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
nodding +, spreading +, drooping +, erect +, ascending +  and arching +
1.5 cm15 mm <br />0.015 m <br /> (2.7 cm27 mm <br />0.027 m <br />) +
crassinucellate +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
deciduous +
pinnate +, dentate +, serrate +  and entire +
toothed +, unlobed +  and lobed +
6-10-loculed +
inferior +  and superior +
biseriate +  and clustered +
collateral +  and basal +
1 cm10 mm <br />0.01 m <br /> (5.5 cm55 mm <br />0.055 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.04 cm10.4 mm <br />0.0104 m <br />) +
0 (?) +  and 4 (?) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.43 cm4.3 mm <br />0.0043 m <br />) +
Pink (?) +, Ivory (?) +  and White (?) +
free +  and distinct +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.26 cm2.6 mm <br />0.0026 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Flowering Mar–May +  and fruiting May–Jun. +
adnate +, free +, connate +  and distinct +
purplish black +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Prelim. Cat., +
4-17-flowered +
not arillate +
0.27 cm2.7 mm <br />0.0027 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
persistent +
free +  and distinct +
spreading +  and ascending +
triangular +  and lanceolate +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.27 cm2.7 mm <br />0.0027 m <br />) +
free +  and distinct +
stoloniferous +
erect +  and ascending +
1 +  and 100 +
0.47 cm4.7 mm <br />0.0047 m <br /> (0.58 cm5.8 mm <br />0.0058 m <br />) +
persistent +
connate +  and distinct +
basal +, lateral +, subterminal +  and terminal +
elongate +
0.34 cm3.4 mm <br />0.0034 m <br /> (0.47 cm4.7 mm <br />0.0047 m <br />) +
Amelanchier canadensis subsp. obovalis +
Amelanchier canadensis var. obovalis +
Amelanchier canadensis +
variety +
6 +  and 15 +
inconspicuous +