Crataegus ×atrorubens

Crataegus ×atrorubens Ashe

J. Elisha Mitchell Sci. Soc. 16: 78. 1900.

Endemic
Treatment appears in FNA Volume 9. Treatment on page 636. Mentioned on page 531.

Shrubs or trees, 40–60 dm. Stems: twigs: new growth not recorded, 1-year old bright redbrown, older grayish; thorns on twigs not recorded. Leaves: petiole slender, length 30–50% blade, adaxial sulcus pubescent; blade ovate, (3–) 4–7 cm, base rounded to very broadly cuneate, lobes 3 or 4 per side, sinuses very shallow to ± deep, max LII 5–20%, lobe apex acute, margins serrulate, venation camptodromous, veins 4 or 5 (or 6) per side, apex acute, abaxial surface with axillary hair-tufts extending ± on basal part of leaf, adaxial sparsely appressed-hairy young, glabrescent. Inflorescences 6–14-flowered; branches sparsely pubescent; bracteoles usually persistent, linear-spatulate, margins glandular, sometimes caducous, linear, membranous, margins eglandular. Flowers 15–18 mm diam.; hypanthium densely canescent; sepals narrow, margins glandular-serrate; stamens 20, anther color not recorded; styles 4 or 5. Pomes dark red, orbicular, 9–11 mm diam., glabrous; sepals erose or ± reflexed; pyrenes 4 or 5, dorsally grooved, sides plane.


Phenology: Flowering Apr; fruiting Sep–Oct.
Habitat: Riverine flats
Elevation: 200 m

Discussion

Crataegus ×atrorubens is probably a hybrid of C. viridis × C. mollis, originating near St. Louis. The C. viridis parentage is apparent in the axillary tufts of hairs on the abaxial leaf surfaces and in the occasional presence of eglandular bracteoles; the C. mollis parentage is apparent in leaf size and shape. This handsome tree is much favored by arboreta; a quite different C. crus-galli hybrid is often misidentified as it.

Selected References

None.

Lower Taxa

None.
... more about "Crataegus ×atrorubens"
glabrescent +  and appressed-hairy +
0.8 cm8 mm <br />0.008 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
James B. Phipps +
Crataegus ×atrorubens Ashe +
compound +  and simple +
opposite +  and alternate +
cuneate +  and rounded to very +
3 cm30 mm <br />0.03 m <br /> (4 cm40 mm <br />0.04 m <br />) +
4 cm40 mm <br />0.04 m <br /> (7 cm70 mm <br />0.07 m <br />) +
linear-spatulate +
adnate +  and distinct +
crowded +, scattered +  and alternate +
not +  and aggregated +
1.5 cm15 mm <br />0.015 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
not +  and aggregated +
yellow +  and red or purplish +
0.6 cm6 mm <br />0.006 m <br /> (2 cm20 mm <br />0.02 m <br />) +
grayish +  and bright redbrown +
older +, old +  and new +
tomentose +  and glabrous +
Riverine flats +
constricted +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
crassinucellate +
deciduous +
eglandular +  and camptodromous +
glandular-serrate +  and serrulate +
serrate +  and crenate +
inferior +  and superior +
biseriate +  and clustered +
collateral +  and basal +
0.8 cm8 mm <br />0.008 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
elliptic +  and circular +
0 (?) +  and 4 (?) +
free +  and distinct +
Flowering Apr +  and fruiting Sep–Oct. +
adnate +, free +, connate +  and distinct +
dark gray-brown +  and russet +
exfoliating +  and corrugated +
0.9 cm9 mm <br />0.009 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
orbicular +
J. Elisha Mitchell Sci. Soc. +
not arillate +
persistent +
free +  and distinct +
triangular +
1-50-flowered +  and few-leaved +
shallow +  and more or less deep +
free +  and distinct +
branched +  and simple +
persistent +
distinct +
exsert +  and lateral +
elongate +
glabrous +  and tomentose +
Crataegus ×atrorubens +
Crataegus +
species +
6 cm60 mm <br />0.06 m <br /> (10 cm100 mm <br />0.1 m <br />) +
1 cm10 mm <br />0.01 m <br /> (6 cm60 mm <br />0.06 m <br />) +
craspedodromous +  and gland-tipped +
inconspicuous +
5 +  and 4 +
tree +  and shrub +