Crataegus (sect. Coccineae) ser. Aestivales
Man. Cult. Trees ed. 2, 366. 1940.
Shrubs or trees, 30–120 dm, main trunk dominant. Stems: trunk bark dark gray, scaling; freshly exposed bark gray; twigs: new growth glabrous or rufous-tomentose, 1-year old dark chestnut-brown to dark gray, older gray; thorns on twigs few to numerous (less abundant on older shoots in C. aestivalis), straight, 2-years old dark gray to black, stout, 1–5 cm. Leaves: petiole short, length 10–16% blade, glabrous or rufous-tomentose, eglandular; blade elliptic to narrowly oblanceolate, lance-elliptic, or ovate, 2.5–7 cm, somewhat coriaceous, base cuneate, lobes 0 or sinuate, sinuses shallow, lobe apex obtuse, margins finely crenate-serrate to obscurely serrulate or entire, glandular, sometimes eglandular, venation ± craspedodromous, veins (3 or) 4–9 (or 10) per side, apex acute to obtuse, glossy to matte, surfaces glabrous or hairy. Inflorescences appearing before or with young leaves, 2–6-flowered, ± umbellate; branches glabrous or hairy; bracteoles often caducous, narrow or oblong-linear, membranous, margins glandular. Flowers 12–25 (–30) mm diam.; hypanthium glabrous, rarely rufous-tomentose; sepals triangular, much shorter than petals, margins entire or glandular-serrate; petals white to sometimes pale-pink in C. opaca; stamens 20, anthers pink to reddish or rose; styles 4 or 5. Pomes ripe May–late June, usually red, sometimes yellow, suborbicular, 8–15 (–20) mm diam., glabrous; flesh succulent; sepals usually ± recurved, very short, accrescent; pyrenes 4 or 5.
North America, Mexico, in Europe
Species 3 (3 in the flora).
Members of ser. Aestivales are found in wetlands from eastern Texas to North Carolina. Two species are largely allopatric (Crataegus aestivalis and C. opaca) and a third (C. ×rufula) is more or less intermediate between the first two and occurs where the ranges of the other two overlap. The mayhaws are distinct in precocious flowering, habitat, exceptionally early fruit ripening, and more or less umbellate inflorescences. Also, uniquely in sect. Coccineae, it appears that some thorns may be indeterminate.
The fruit is widely consumed in foods such as pies, jellies, jams, and wine. The species are cultivated in home gardens and are also, on a small scale, commercially grown and processed.
|1||Leaf blades elliptic to oblanceolate or narrowly so, margins eglandular (except sometimes on teeth), entire proximally, serrulate to crenate in distal 1/2, abaxial surfaces glabrous except for tufts of usually pale gray hair in vein axils, adaxial ± shiny.||Crataegus aestivalis|
|1||Leaf blades ± elliptic to lance-elliptic, sometimes broadly elliptic to ovate, margins gland-dotted, sinuate, abaxial surfaces rufous-tomentose, adaxial usually dull||> 2|
|2||Leaf blades ± elliptic to lance-elliptic, sometimes broadly elliptic, 5–7 cm, veins 5–9(or 10) per side; inflorescence branches absent or glabrous.||Crataegus opaca|
|2||Leaf blades elliptic to ovate, 2.5–4.5 cm, veins 3–5 per side; inflorescence branches glabrous or rufous-tomentose.||Crataegus ×rufula|