Shrubs or trees, 40–100 [–120] dm. Stems: twigs: new growth glabrous; stipules of flowering shoots ± entire; thorns on twigs few to numerous, usually indeterminate and terminal, 0.7–1 cm, when determinate and lateral ± stout, to 2.4 cm. Leaves: petiole slender, 1–3 cm, glabrous, eglandular; blade ovate to deltate, 1.2–5.5 cm, base cuneate to truncate, lobes 1–3 per side, sinuses usually deep, lobe apex acute, margins weakly and often few-toothed at lobe apices, veins 2–5 per side, apex acute, abaxial surface paler green, villous on major veins, adaxial ± lustrous dark green, glabrous or mainly villous. Inflorescences 5–15-flowered, ± lax; branches glabrous [to villous]; bracteole margins entire or bearing few to numerous glands on small irregular protuberances or on small pegs. Flowers 8–16 mm diam.; hypanthium glabrous [to lanate]; sepals 1.5–2.5 mm, margins entire, apex acute or obtuse; stamens 15–20, anthers pink-purple; style 1. Pomes sometimes bright, usually dark red, orbicular to ± cylindric, 6–11 mm diam.; sepals reflexed; pyrene 1.2n = 34, 51.


Phenology: Flowering Apr–May; fruiting Sep–Oct.
Habitat: Brush, woodland edges and old pastures in medium rainfall areas
Elevation: 10–800 m

Distribution

V9 834-distribution-map.jpg

Introduced; B.C., N.B., N.S., Ont., P.E.I., Que., Calif., Colo., Conn., Del., Ill., Ind., Maine, Mass., Mich., Minn., N.H., N.J., N.Y., Ohio, Oreg., Pa., R.I., Vt., Wash., Wis., Europe, sw Asia, n Africa, also in South America (Argentina), also in South America (Chile), s Africa, Pacific Islands (New Zealand), Australia

Discussion

Variety monogyna differs from var. lasiocarpa (Lange) K. I. Christensen in the absence of villous abaxial leaf surfaces and inflorescences. Variety monogyna is distributed throughout the area of the species; var. lasiocarpa primarily occurs in the Balkan, Iranian, and Mediterranean areas, and is most common in Greece.

Variety monogyna is locally common in the Pacific Northwest and adjacent Canada, as well as from the Great Lakes to the Atlantic. The variety hybridizes in North America with the diploid species Crataegus suksdorfii and rarely with C. punctata. The hybrid with C. laevigata, C. ×media Bechstein, is well known in the wild in Europe; only its cultivars are seen in North America.

Selected References

None.

Lower Taxa

None.
villous +  and glabrous +
0.8 cm8 mm <br />0.008 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
pink +  and purple +
James B. Phipps +
Jacquin +
exfoliating +
compound +  and simple +
opposite +  and alternate +
cuneate +  and truncate +
8 cm80 mm <br />0.08 m <br /> (12 cm120 mm <br />0.12 m <br />) +
ovate +  and deltate +
1.2 cm12 mm <br />0.012 m <br /> (5.5 cm55 mm <br />0.055 m <br />) +
bearing few to numerous glands +  and entire +
adnate +  and distinct +
crowded +, scattered +  and alternate +
B.C. +, N.B. +, N.S. +, Ont. +, P.E.I. +, Que. +, Calif. +, Colo. +, Conn. +, Del. +, Ill. +, Ind. +, Maine +, Mass. +, Mich. +, Minn. +, N.H. +, N.J. +, N.Y. +, Ohio +, Oreg. +, Pa. +, R.I. +, Vt. +, Wash. +, Wis. +, Europe +, sw Asia +, n Africa +, also in South America (Argentina) +, also in South America (Chile) +, s Africa +, Pacific Islands (New Zealand) +  and Australia +
not +  and aggregated +
10–800 m +
0.8 cm8 mm <br />0.008 m <br /> (1.6 cm16 mm <br />0.016 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 />) +
Brush, woodland edges and old pastures in medium rainfall areas +
constricted +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
crassinucellate +
deciduous +
few-toothed +
inferior +  and superior +
biseriate +  and clustered +
collateral +  and basal +
small +
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 +
post-mature +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
Flowering Apr–May +  and fruiting Sep–Oct. +
adnate +, free +, connate +  and distinct +
dark gray-brown +  and russet +
exfoliating +  and corrugated +
0.6 cm6 mm <br />0.006 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
orbicular +  and more or less cylindric +
Fl. Austriac. +
not arillate +
persistent +
free +  and distinct +
triangular +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
1-50-flowered +  and few-leaved +
craspedodromous +
Introduced +
free +  and distinct +
branched +  and simple +
elongate +
persistent +
distinct +
exsert +  and lateral +
elongate +
glabrous +  and tomentose +
Crataegus monogyna var. monogyna +
Crataegus monogyna +
variety +
6 cm60 mm <br />0.06 m <br /> (10 cm100 mm <br />0.1 m <br />) +
curved +  and straight +
indeterminate +
slender +
0 cm0 mm <br />0 m <br /> (2.4 cm24 mm <br />0.024 m <br />) +
craspedodromous +  and gland-tipped +
inconspicuous +
exfoliating +
1 +  and few +
indeterminate +  and determinate +
few +  and numerous +
2 +  and 5 +
tree +  and shrub +