Crataegus macracantha

Loddiges ex Loudon

Arbor. Frutic. Brit. 2: 819, figs. 572, 573. 1838.

Common names: Large-thorn hawthorn aubépine á épines longues
EndemicIllustrated
Synonyms: Crataegus divida Sargent C. laneyi Sargent C. macracantha var. occidentalis (Britton) Eggleston C. macracantha var. pertomentosa (Ashe) Kruschke C. occidentalis Schrader ex Link C. pertomentosa C. succulenta var. macracantha (Loddiges ex Loudon) Eggleston C. succulenta var. occidentalis (Britton) E. J. Palmer C. succulenta var. pertomentosa (Ashe) E. J. Palmer
Treatment appears in FNA Volume 9. Treatment on page 520. Mentioned on page 502, 504, 516, 517, 518, 519, 521, 564, 640.

Shrubs, 40–60 (–80) dm. Stems: older trunks usually bearing compound thorns; twigs: new growth reddish green, usually glabrous, 1-year old dark, shiny reddish-brown, 2–3-years old becoming dark gray, older ± paler gray; thorns on twigs usually numerous, recurved, shiny, dark blackish brown, older gray, stout, 3–7 (–11) cm. Leaves: petiole 1–2 cm, narrowly winged distally, glabrous, eglandular, rarely glandular (on distal wing); blade narrowly rhombic-elliptic to broadly rhombic-ovate (sometimes narrowly obovate), 4–7 (–10) cm widest near middle, subcoriaceous mature (then often blue-green), base cuneate (constricted into winged distal part of petioles), lobes 3–5 per side, sinuses obscure to well-marked, LII 5–15%, lobe apex usually obtuse, margins serrate except near bases, veins 6–8 per side, impressed, apex acute to obtuse, abaxial surface glabrous (except in var. pertomentosa), adaxial scabrous-pubescent young. Inflorescences 15–30-flowered; branches pubescent or glabrous; bracteoles ± pallid, linear, margins glandular, sometimes long-stipitate-glandular. Flowers 13–19 mm diam.; hypanthium glabrous or sparsely to densely pubescent; sepals narrowly triangular, 4–6 mm, margins glandular-serrate to glandular-laciniate, abaxial pubescence not recorded, adaxially glabrous; stamens 10, anthers white or pink, 0.9–1.2 mm; styles 2 or 3. Pomes: brilliant scarlet (west) to full crimson (east), suborbicular, 7–12 mm diam., succulent mature, glabrous or pubescent; sepals spreading-reflexed; pyrenes 2 or 3, sides pitted. 2n = 68.


Phenology: Flowering Apr–Jun; fruiting Sep–Oct.
Habitat: Brush
Elevation: 20–1600 m

Distribution

V9 879-distribution-map.jpg

Alta., B.C., Man., N.B., Ont., Que., Sask., Ariz., Colo., Conn., Ill., Ind., Iowa, Kans., Md., Mass., Mich., Minn., Mo., Mont., Nebr., N.H., N.Mex., N.Y., N.Dak., Ohio, Oreg., Pa., R.I., S.Dak., Utah, Vt., Va., Wash., W.Va., Wis., Wyo.

Discussion

Crataegus macracantha is the most widespread North American hawthorn and one of the more variable. Variation is particularly great in Quebec and Montana. Attempts to package the variation into named taxa have hitherto run into the problems that the type is an illustration of inadequate quality and that authors have been insufficiently aware of the total variation. Two common eastern forms are similar white-anthered and pink-anthered with abaxially glabrous, broadly elliptic-ovate leaves, shallowly and sharply lobed, and fruit ripening directly from green to red; these have the longest thorns in the species, and both have been treated as if typical.

Crataegus occidentalis, a white-anthered, intermontane form with leaves similar to the foregoing usually has shorter thorns and fruit ripening to red through a characteristic orange or salmon stage. Pink-anthered C. pertomentosa, with leaves of a similar shape but abaxially pubescent to tomentose grows on the Great Plains. The last two forms have been treated as varieties. Other striking variants have brilliant red bracteoles or strongly convex leaves (both from Montana) and entire-margined sepals (C. integriloba Sargent from Quebec). Some rare forms have glabrous inflorescences. Some populations in northwestern Montana, otherwise much like a common pink-anthered sympatric form, have glandular petioles and may represent introgression from another species.

Crataegus macracantha often forms suckering thickets in the east.

Selected References

None.

Lower Taxa

None.
... more about "Crataegus macracantha"
scabrous-pubescent +
glabrescent +  and scabrous-pubescent +
0.8 cm8 mm <br />0.008 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
pink +  and white +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
James B. Phipps +
Loddiges ex Loudon +
compound +  and simple +
opposite +  and alternate +
cuneate +
Crataegus sect. Macracanthae +
less ovate or rhombic-elliptic +  and rhombic-elliptic +
7 cm70 mm <br />0.07 m <br /> (10 cm100 mm <br />0.1 m <br />) +
narrowly rhombic-elliptic +  and broadly rhombic-ovate +
4 cm40 mm <br />0.04 m <br /> (7 cm70 mm <br />0.07 m <br />) +
glabrous +  and pubescent +
adnate +  and distinct +
crowded +, scattered +  and alternate +
Large-thorn hawthorn +  and aubépine á épines longues +
Alta. +, B.C. +, Man. +, N.B. +, Ont. +, Que. +, Sask. +, Ariz. +, Colo. +, Conn. +, Ill. +, Ind. +, Iowa +, Kans. +, Md. +, Mass. +, Mich. +, Minn. +, Mo. +, Mont. +, Nebr. +, N.H. +, N.Mex. +, N.Y. +, N.Dak. +, Ohio +, Oreg. +, Pa. +, R.I. +, S.Dak. +, Utah +, Vt. +, Va. +, Wash. +, W.Va. +, Wis. +  and Wyo. +
not +  and aggregated +
20–1600 m +
1.3 cm13 mm <br />0.013 m <br /> (1.9 cm19 mm <br />0.019 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 />) +
paler gray +, dark gray +, reddish-brown +, dark +  and reddish green +
older +, old +  and new +
Brush +
glabrous or +  and sparsely densely pubescent +
constricted +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
crassinucellate +
deciduous +
craspedodromous +
long-stipitate-glandular +
glandular-serrate +  and glandular-laciniate +
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 +
post-mature +
eglandular +  and winged +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
Flowering Apr–Jun +  and fruiting Sep–Oct. +
adnate +, free +, connate +  and distinct +
dark gray-brown +  and russet +
exfoliating +  and corrugated +
scarlet +  and full crimson +
0.7 cm7 mm <br />0.007 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
pubescent +  and glabrous +
suborbicular +
succulent +
Arbor. Frutic. Brit. +
not arillate +
persistent +
free +  and distinct +
glandular-denticulate +  and glandular-laciniate +
spreading-reflexed +
triangular +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
1-50-flowered +  and few-leaved +
obscure +  and well-marked +
Endemic +  and Illustrated +
free +  and distinct +
branched +  and simple +
persistent +
distinct +
exsert +  and lateral +
elongate +
glabrous +  and tomentose +
Crataegus divida +, C. laneyi +, C. macracantha var. occidentalis +, C. macracantha var. pertomentosa +, C. occidentalis +, C. pertomentosa +, C. succulenta var. macracantha +, C. succulenta var. occidentalis +  and C. succulenta var. pertomentosa +
Crataegus macracantha +
Crataegus (sect. Macracanthae) ser. Macracanthae +
species +
7 cm70 mm <br />0.07 m <br /> (11 cm110 mm <br />0.11 m <br />) +
gray +, brown +  and dark blackish +
slender +
3 cm30 mm <br />0.03 m <br /> (7 cm70 mm <br />0.07 m <br />) +
craspedodromous +  and gland-tipped +
inconspicuous +
less erect +  and oblique +
1 +  and several +
determinate +
6 +  and 8 +