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aubépine monogyne, common hawthorn, English hawthorn, hawthorn, one-seed hawthorn, singleseed hawthorn

O'kennon's hawthorn, O'kennon hawthorn

Habit Shrubs or trees, 30–100(–140) dm.
Stems

usually single-trunked; 1-year old twigs deep mahogany, shiny, older gray-brown;

thorns on twigs single, slightly recurved, usually brown young, 2 cm.

Leaves

(fall color plum to crimson or light crimson);

petiole 1–2 cm, pubescence and glandularity not recorded;

blade elliptic to broadly elliptic, sometimes ± narrowly ovate or rhombic, 4–6 cm, lobes 2 or 3 per side, lobe apex acute to ± obtuse, margins serrate, venation craspedodromous, veins 4 per side, apex subacute to obtuse, abaxial surface glabrous except on veins, adaxial finely appressed-pubescent.

Inflorescences

12–20-flowered;

branches glabrous, sometimes ± sparsely pubescent;

bracteole margins stipitate-glandular.

Flowers

15–20 mm diam.;

hypanthium glabrous;

sepals broadly triangular, 3 mm, margins obscurely glandular;

stamens 10–12, anthers pale pink;

styles 3 or 4.

Pomes

red-burgundy to chestnut or reddish brown (late Aug), deep purple to black at full maturity, ± ampulliform-orbicular, 8–10 mm diam., glabrous;

sepal remnants reflexed, apex obtuse;

pyrenes 3 or 4, sides ± eroded, sometimes plane.

2n

= 68.

Crataegus monogyna

Crataegus okennonii

Phenology Flowering May; fruiting Sep–Oct.
Habitat Mesic thickets, natural hedgerows, scrub
Elevation 300–700 m (1000–2300 ft)
Distribution
from FNA
CA; CO; CT; DE; IL; IN; MA; ME; MI; MN; NH; NJ; NY; OH; OR; PA; RI; VT; WA; WI; BC; NB; NS; ON; PE; QC; Europe; w Asia; n Africa [Introduced also in South America, s Africa, Pacific Islands, Australia]
[WildflowerSearch map]
[BONAP county map]
from FNA
ID; MT; WA; BC
Discussion

Varieties 2 (1 in the flora).

Crataegus monogyna was introduced early to North America to be used for agricultural hedges, a practice now discontinued on this continent.

Cultivar 'Crimson Cloud,' often under an incorrect species name, is widely cultivated as an ornamental.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Crataegus okennonii is common in southern interior British Columbia and the eastern half of northern Washington, extending to Idaho and northwestern Montana, usually along streams or other water sources.

Although Crataegus okennonii is treated as a microspecies of C. douglasii by T. A. Dickinson et al. (2008), the ease with which most specimens can be identified and its relatively wide range merits taxonomic recognition. The plants are often distinctively tall, usually with a straight trunk.

While Crataegus okennonii fits towards an extreme of C. douglasii on individual characters, for example, relatively short thorns, broad, shallowly incised leaves, and larger flowers, the ensemble is unique. Further, putatively later anthesis, crimson fall foliage, and the peculiar color of the subripe fruit, red, reddish brown, or deep tan, are unknown for C. douglasii.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 9, p. 497. FNA vol. 9, p. 513.
Parent taxa Rosaceae > subfam. Amygdaloideae > tribe Maleae > Crataegus > sect. Crataegus > ser. Crataegus Rosaceae > subfam. Amygdaloideae > tribe Maleae > Crataegus > sect. Douglasia > ser. Douglasianae
Sibling taxa
C. aemula, C. aestivalis, C. alabamensis, C. alleghaniensis, C. annosa, C. aprica, C. aquacervensis, C. ashei, C. atrovirens, C. attrita, C. austromontana, C. beata, C. berberifolia, C. biltmoreana, C. brachyacantha, C. brainerdii, C. brazoria, C. brittonii, C. buckleyi, C. calpodendron, C. castlegarensis, C. chrysocarpa, C. coccinea, C. coccinioides, C. cognata, C. collina, C. colonica, C. communis, C. compacta, C. condigna, C. craytonii, C. crocea, C. crus-galli, C. cupressocollina, C. delawarensis, C. dispar, C. dodgei, C. douglasii, C. egens, C. egregia, C. enderbyensis, C. erythropoda, C. exilis, C. eximia, C. extraria, C. fecunda, C. flabellata, C. flava, C. florens, C. floridana, C. florifera, C. fluviatilis, C. formosa, C. frugiferens, C. furtiva, C. gattingeri, C. gaylussacia, C. gilva, C. greggiana, C. harbisonii, C. holmesiana, C. ignava, C. incilis, C. integra, C. intricata, C. invicta, C. iracunda, C. irrasa, C. jesupii, C. jonesiae, C. lacrimata, C. laevigata, C. lanata, C. lancei, C. lanuginosa, C. lassa, C. laurentiana, C. leonensis, C. lepida, C. levis, C. lumaria, C. macracantha, C. macrosperma, C. magniflora, C. margarettae, C. marshallii, C. mendosa, C. meridiana, C. mira, C. mollis, C. munda, C. nananixonii, C. neobushii, C. nitida, C. oakesiana, C. okanaganensis, C. okennonii, C. opaca, C. opima, C. orbicularis, C. ouachitensis, C. padifolia, C. pennsylvanica, C. persimilis, C. pexa, C. phaenopyrum, C. phippsii, C. pinetorum, C. populnea, C. prona, C. pruinosa, C. pulcherrima, C. punctata, C. purpurella, C. quaesita, C. reverchonii, C. rivularis, C. rivuloadamensis, C. rivulopugnensis, C. roribacca, C. rubella, C. rubribracteolata, C. saligna, C. sargentii, C. scabrida, C. schizophylla, C. schuettei, C. segnis, C. senta, C. sheila-phippsiae, C. sheridana, C. shuswapensis, C. sororia, C. spathulata, C. spes-aestatum, C. stolonifera, C. stonei, C. submollis, C. suborbiculata, C. succulenta, C. tecta, C. teres, C. texana, C. tracyi, C. triflora, C. turnerorum, C. uniflora, C. ursopedensis, C. venusta, C. viridis, C. visenda, C. wattiana, C. williamsii, C. wootoniana, C. ×atrorubens, C. ×bicknellii, C. ×coleae, C. ×collicola, C. ×disperma, C. ×dispessa, C. ×fretalis, C. ×incaedua, C. ×kelloggii, C. ×latebrosa, C. ×lucorum, C. ×rufula, C. ×sicca, C. ×vailiae
C. aemula, C. aestivalis, C. alabamensis, C. alleghaniensis, C. annosa, C. aprica, C. aquacervensis, C. ashei, C. atrovirens, C. attrita, C. austromontana, C. beata, C. berberifolia, C. biltmoreana, C. brachyacantha, C. brainerdii, C. brazoria, C. brittonii, C. buckleyi, C. calpodendron, C. castlegarensis, C. chrysocarpa, C. coccinea, C. coccinioides, C. cognata, C. collina, C. colonica, C. communis, C. compacta, C. condigna, C. craytonii, C. crocea, C. crus-galli, C. cupressocollina, C. delawarensis, C. dispar, C. dodgei, C. douglasii, C. egens, C. egregia, C. enderbyensis, C. erythropoda, C. exilis, C. eximia, C. extraria, C. fecunda, C. flabellata, C. flava, C. florens, C. floridana, C. florifera, C. fluviatilis, C. formosa, C. frugiferens, C. furtiva, C. gattingeri, C. gaylussacia, C. gilva, C. greggiana, C. harbisonii, C. holmesiana, C. ignava, C. incilis, C. integra, C. intricata, C. invicta, C. iracunda, C. irrasa, C. jesupii, C. jonesiae, C. lacrimata, C. laevigata, C. lanata, C. lancei, C. lanuginosa, C. lassa, C. laurentiana, C. leonensis, C. lepida, C. levis, C. lumaria, C. macracantha, C. macrosperma, C. magniflora, C. margarettae, C. marshallii, C. mendosa, C. meridiana, C. mira, C. mollis, C. monogyna, C. munda, C. nananixonii, C. neobushii, C. nitida, C. oakesiana, C. okanaganensis, C. opaca, C. opima, C. orbicularis, C. ouachitensis, C. padifolia, C. pennsylvanica, C. persimilis, C. pexa, C. phaenopyrum, C. phippsii, C. pinetorum, C. populnea, C. prona, C. pruinosa, C. pulcherrima, C. punctata, C. purpurella, C. quaesita, C. reverchonii, C. rivularis, C. rivuloadamensis, C. rivulopugnensis, C. roribacca, C. rubella, C. rubribracteolata, C. saligna, C. sargentii, C. scabrida, C. schizophylla, C. schuettei, C. segnis, C. senta, C. sheila-phippsiae, C. sheridana, C. shuswapensis, C. sororia, C. spathulata, C. spes-aestatum, C. stolonifera, C. stonei, C. submollis, C. suborbiculata, C. succulenta, C. tecta, C. teres, C. texana, C. tracyi, C. triflora, C. turnerorum, C. uniflora, C. ursopedensis, C. venusta, C. viridis, C. visenda, C. wattiana, C. williamsii, C. wootoniana, C. ×atrorubens, C. ×bicknellii, C. ×coleae, C. ×collicola, C. ×disperma, C. ×dispessa, C. ×fretalis, C. ×incaedua, C. ×kelloggii, C. ×latebrosa, C. ×lucorum, C. ×rufula, C. ×sicca, C. ×vailiae
Subordinate taxa
C. monogyna var. monogyna
Name authority Jacquin: Fl. Austriac. 3: 50, plate 292, fig. 1. (1775) J. B. Phipps: Sida 18: 170, figs. 2, 4a–c, f. (1998)
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