Flora of North America species comparison

The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Crataegus castlegarensis

Crataegus williamsii

Castlegar hawthorn, Castlegar hawthorne, hawthorn

Williams' hawthorn
Habit Shrubs, 25–50 dm. Shrubs, 40–60(–100) dm.
Stems

erect;

branches spreading; 1-year old twigs brown;

thorns on twigs usually branched, some paired or in triads, straight to slightly recurved, dark brown with blackish tip young, 2–3 cm.

expanding bud-scales conspicuous, coral red;

twigs: new growth glabrous, 1-year old deep reddish brown;

thorns on twigs ± straight to slightly recurved, black, sometimes dark purple young, older paler, shiny, ± slender, 3–4 cm.
Leaves

petiole 0.7–1.5 cm, pubescent, eglandular;

blade oblanceolate to ovate-rhombic, 3.5–6 cm, lobes 3 or 4 per side, sinuses shallow to deep, lobe apex usually acute, margins serrate, teeth apices finally glandular young, venation craspedodromous, veins 4 or 5 per side, apex broadly triangular, abaxial surface sparsely hairy or glabrous except on veins, adaxial conspicuously appressed-pubescent young, glabrescent except on midvein.

petiole 2–3 cm, ± hairy, eglandular or glandular;

blade rhombic to elliptic, 4–6 cm, thin, base cuneate, lobes 2 or 3 per side, short, lobe apex acute, margins ± evenly sharp-serrate except at base, teeth ± inconspicuously gland-tipped, veins 4 or 5(or 6) per side, apex acute, abaxial surface glabrous, veins hairy, adaxial shortly and densely appressed-hairy.
Inflorescences

12–20-flowered;

branches sparsely to densely pubescent;

bracteole margins stipitate-glandular.

8–20-flowered;

branches sparsely villous;

bracteole margins sessile-glandular.
Flowers

12 mm diam.;

hypanthium pubescent or glabrous;

sepals triangular, 3 mm, margins remotely glandular-serrate;

stamens 10, anthers pink;

styles 3 or 4.

16 mm diam.;

hypanthium glabrous or densely villous externally;

sepals ± narrowly triangular, 4–7 mm, margins finely glandular-serrate, abaxially glabrous;

stamens 10, anthers pink;

styles 3 or 4(or 5).
Pomes

crimson (mid Aug) turning to reddish plum or, ultimately, blackish purple, orbicular, ± oblate (recessed at junction with pedicel), 10 mm diam., sparsely pilose;

sepals reflexed, apex obtuse;

pyrenes 3 or 4, sides usually pitted.

usually pale red young, bright red (late Aug), deepening to oxblood red or darker mature (Sep), usually short-ellipsoid, 8 mm diam., longer than wide, sparsely villous;

sepals not thickened or enlarged, spreading to reflexed, narrow, 4–7 mm;

pyrenes 3 or 4(or 5), sides variably pitted.
2n

= 68.

Crataegus castlegarensis

Crataegus williamsii
Phenology Flowering May–Jun; fruiting Sep–Oct. Flowering May–Jun; fruiting Sep–Oct.
Habitat Mesic brush Scrub
Elevation 300–1200 m (1000–3900 ft) 700–1000 m (2300–3300 ft)
Distribution
from FNA
CA; ID; MT; OR; UT; WA; WY; AB; BC; SK
[WildflowerSearch map]
from FNA
MT
Discussion

Crataegus castlegarensis occurs from around the northern Okanagan, British Columbia, to the northern California Coast Ranges, to northwestern Montana, and the Rocky Mountains to northeast of Salt Lake City, Utah. The species occurs also in the Cypress Hills of Alberta and Saskatchewan; it is found in habitats similar to those of C. douglasii and is at least as abundant as that species in a number of parts of its range.

Crataegus castlegarensis is readily recognized by a combination of hairy inflorescence branches, pomes more or less orbicular, crimson or burgundy (with irregular earlier ripening) around the third week of August, soon becoming purple, often when nearby C. douglasii is already black, as well as a tendency to possess thorns on the young twigs branched at the base to become double, triple, or even sometimes quadruple. Such multiple thorns, though sometimes abundant on a bush, are more often few and may require searching for. Inflorescence pubescence, as in other species with this characteristic, may become sparse by fruiting. Crataegus castlegarensis is most similar to C. douglasii; its fruit is usually more orbicular, even oblately so, than is normal in that species, sometimes even with a recessed junction to the pedicel like an apple.

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

Crataegus williamsii occurs in the Clark Fork and Flathead drainage basins of northwestern Montana; possible records for Idaho require more study. The species is notable for its extremely late anthesis, after sympatric C. macracantha; it is the last hawthorn to flower in its area of occurrence. The immature fruit is bright red, in contrast to its later duller color. The fall color of the foliage is predominantly crimson burgundy or a pallid version thereof. Crataegus williamsii is the most distinct member of ser. Purpureofructus because of its relatively small and delicate, spreading to reflexed fruiting sepals (versus accrescent, long, erect-patent) and its lack of purple to black colored, fully mature fruit. See also comments under 26. C. macracantha.

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Source FNA vol. 9, p. 513. FNA vol. 9, p. 504.
Parent taxa Rosaceae > subfam. Amygdaloideae > tribe Maleae > Crataegus > sect. Douglasia > ser. Douglasianae Rosaceae > subfam. Amygdaloideae > tribe Maleae > Crataegus > sect. Douglasia > ser. Purpureofructus
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. 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. 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. 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. 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
Name authority J. B. Phipps & O'Kennon: Sida 20: 121, figs. 3, 4. (2002) Eggleston: Bull. Torrey Bot. Club 36: 641. (1909)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Fabaceae, Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America, OregonFlora, UW Burke Herbarium

The species comparison tool is brought to you by:
Northwest Wildflowers