37. Crataegus berberifolia Torrey & A. Gray, Fl. N. Amer. 1: 469. 1840.
Barberry-leaved hawthorn
Shrubs or trees, 60 dm. Stems: twigs: new growth ˂orange-brown or green tinged with red˃, ± pubescent, 1-year old brown, older gray; thorns on twigs ± straight or recurved, 2-years old shiny black to chestnut brown, fine or stouter, (2–)3–4(–6.5) cm. Leaves: petiole 4–6 mm, length 13–18% blade, glabrescent, eglandular; blade narrowly obovate to oblanceolate, (2.5–)3(–4) cm, coriaceous, base narrowly cuneate, lobes 0, margins finely crenate or serrate except at base, or only beyond widest part, venation craspedodromous, veins 4–6 per side, apex subacute to obtuse, ˂lustrous˃, abaxial surface ± densely pilose on veins, sometimes pubescent on surface, adaxial hairy young, glabrescent or becoming scabrous. Inflorescences 8–12-flowered; branches densely pubescent; bracteoles linear, margins glandular. Flowers 10–20 mm diam.; hypanthium villous or glabrous; sepals 3–5 mm, margins entire, abaxially glabrous; stamens 10 or 20, anthers cream or pink; styles 2 or 3. Pomes reddish to yellow, suborbicular, 8–10 mm diam., glabrous; sepals erose or patent; pyrenes 2 or 3.
Varieties 2 (2 in the flora): sc, se United States.
Crataegus berberifolia is widespread from Texas to Missouri, Florida, and Virginia; it is particularly abundant in Louisiana.
Crataegus berberifolia is little differentiated from some forms of C. crus-galli, except in indumentum; it has relatively small and less variably shaped leaves. Its distribution is quite different. Intermediates with hairy leaves and glabrous inflorescences or nearly glabrous leaves and hairy inflorescences may represent hybrids with C. crus-galli (where they might be reached in the key). Such a situation is found in C. araioclada. Abrasion of the adaxial leaf pubescence may occur, rendering identification more difficult with fruiting material. Crataegus berberifolia has a plethora of yellow and orange-fruited forms, particularly from southern Louisiana. Crataegus fera and C. tersa are red-fruited, C. crocina yellow. The fruit color in the type is unknown; E. J. Palmer (in specimen annotation) called it yellow-orange. A form with exceptionally white-tomentose leaves near Copenhagen, Louisiana, is probably this species. Crataegus regalis var. paradoxa (Sargent) E. J. Palmer, from Missouri and adjacent Kansas and Arkansas, is probably a hybrid between the deeply serrated 'regalis' leaf form of C. crus-galli and a form of C. berberifolia. Two common forms of C. berberifolia occur, treated here as varieties: var. engelmannii with ten pink anthers and var. berberifolia with 20 cream anthers. Forms with 20 pink or ten cream anthers also occur sporadically.
