Crataegus compacta

Sargent

Crataegus S. Michigan, 522. 1907.

Common names: Thames hawthorn
Endemic
Treatment appears in FNA Volume 9. Treatment on page 573. Mentioned on page 572, 574.

Shrubs, erect, 60 dm. Stems: twigs: new growth reddish green, 1-year old tan, 2-years old dull gray; thorns on twigs ± numerous, ± straight to slightly recurved, 2-years old shiny blackish, medium thickness, 1.5–3 cm. Leaves: petiole length 50–75% blade, sparsely glandular; blade trullate to rhombic-ovate, 3–5 cm, thin, base cuneate, lobes 2 or 3 per side, sinuses shallow, lobe apex subacute, margins serrate, teeth 1 mm, veins 4 or 5 per side, apex acute, surfaces glabrous, sometimes adaxial sparsely hairy young. Inflorescences 4–7-flowered; branches glabrous, sparsely punctate; bracteoles sometimes greenish, large, margins short-stipitate-glandular. Flowers 15–18 mm diam.; sepals narrowly triangular, 4–5 mm, margins subentire, abaxial pubescence not recorded; stamens 20, anthers pink to red, 0.3 mm; styles 3 or 4. Pomes usually borne singly, greenish to pinkish or pale-purple, or dull reddish purple, 8–11 mm diam., moderately pruinose (sometimes bracteolate); sepals on collar, spreading, sometimes erose; pyrenes 2 or 3.2n = 34, 51, 68.


Phenology: Flowering May; fruiting Sep–Oct.
Habitat: Scrub, woodland edges, pastures, fencerows
Elevation: 100–300 m

Distribution

V9 974-distribution-map.jpg

Ont., Mich., N.Y., Ohio, Pa., Va., W.Va.

Discussion

Crataegus compacta is common in the Carolinian zone of Ontario and extends to Michigan, New York, and Pennsylvania (where infrequent), and to the Virginia Blue Ridge (reported for Ohio by Palmer).

Crataegus compacta is most similar to C. gattingeri, one of the two most widespread species in the series, but the allopatry of the two, as well as consistent differences in leaf shape, underlines their distinction. The pedicels and hypanthia in young flowers are conspicuously reddish. Similar forms from Pennsylvania, though with ivory anthers, are C. repentina Sargent with 10–20 stamens and minute anthers, and C. varians Sargent with 10–15 stamens.

Selected References

None.

Lower Taxa

None.
... more about "Crataegus compacta"
68 +, 51 +  and 34 +
0.8 cm8 mm <br />0.008 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
pink +  and red +
0.3 cm3 mm <br />0.003 m <br /> (?) +
James B. Phipps +
Sargent +
orangebrown +
thin-exfoliating +  and corrugated +
compound +  and simple +
opposite +  and alternate +
cuneate +
Pruinosae +
8 cm80 mm <br />0.08 m <br /> (12 cm120 mm <br />0.12 m <br />) +
mid +  and dark green +
trullate +  and rhombic-ovate +
3 cm30 mm <br />0.03 m <br /> (5 cm50 mm <br />0.05 m <br />) +
few +  and numerous +
adnate +  and distinct +
crowded +, scattered +  and alternate +
Thames hawthorn +
Ont. +, Mich. +, N.Y. +, Ohio +, Pa. +, Va. +  and W.Va. +
not +  and aggregated +
100–300 m +
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 />) +
gray +, tan +  and reddish green +
old +  and new +
Scrub, woodland edges, pastures, fencerows +
constricted +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
crassinucellate +
deciduous +
sessile +  and craspedodromous +
subentire +
short-stipitate-glandular +
subentire +
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 +
glandular +
Flowering May +  and fruiting Sep–Oct. +
adnate +, free +, connate +  and distinct +
dark gray-brown +  and russet +
exfoliating +  and corrugated +
pruinose +
greenish +  and pinkish or pale-purple or dull reddish purple +
0.8 cm8 mm <br />0.008 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
suborbicular +
Crataegus S. Michigan, +
not arillate +
persistent +
free +  and distinct +
triangular +
nonaccrescent +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
1-50-flowered +  and few-leaved +
free +  and distinct +
branched +  and simple +
persistent +
distinct +
exsert +  and lateral +
elongate +
hairy +  and glabrous +
Crataegus compacta +
Crataegus (sect. Coccineae) ser. Pruinosae +
species +
6 cm60 mm <br />0.06 m <br /> (10 cm100 mm <br />0.1 m <br />) +
straight +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
thick +  and fine +
craspedodromous +  and gland-tipped +
1 cm10 mm <br />0.01 m <br /> (?) +
inconspicuous +
less erect +  and oblique +
1 +  and several +
straight +
determinate +
5 +  and 4 +