About Cercis canadensis L.
Cercis canadensis L., commonly called eastern redbud, is typically 6โ9 m (20โ30 ft) tall at maturity, with an 8โ10 m (26โ33 ft) spread. It generally has a short, often twisted trunk and spreading branches; a 10-year-old tree is usually around 5 m (16 ft) tall. Its bark is dark and smooth when young, becoming scaly with noticeable ridges as it ages, and sometimes has maroon patches. Mature bark is red-brown with deep fissures and a scaly surface. Twigs are slender, zigzag, nearly black, and marked with lighter-colored lenticels; young branchlets are lustrous brown, and darken as they age. Winter buds are tiny, rounded, and dark red to chestnut in color, measuring one-eighth of an inch long with an obtuse shape. Leaves are alternate, simple, heart-shaped (or broadly ovate) with an entire margin, 7โ12 cm (3โ4.5 in, or 2 to 5 inches) long and wide. They are thin and papery, may be slightly hairy on the lower surface, have five to seven nerves, and are cordate or truncate at the base with an acute tip. When newly emerged from the bud, leaves are folded along the midrib and tawny green; when fully grown, they are smooth, dark green on the upper surface and paler beneath, turning bright clear yellow in autumn. Leaf petioles are slender, terete, and enlarged at the base, with caducous stipules. Flowers are showy, 1.5 cm (1โ2 in) long, and range from light to dark magenta pink; white-flowered cultivars are also available. They open in clusters from spring to early summer (April to May), appearing on bare stems before leaves emerge, and sometimes grow directly from the trunk. Flowers grow in clusters of four to eight in fascicles, located at leaf axils, along branches, or on the trunk. Each flower is perfect and papilionaceous, with a dark red, five-toothed, oblique campanulate calyx that is imbricate in bud. The corolla is papilionaceous with five nearly equal pink or rose-colored petals; the upper petal is the smallest, enclosed by the wings in bud and surrounded by the broader keel petals. There are ten stamens inserted in two rows on a thin disk, free, with the inner row shorter than the outer. The pistil has a superior ovary inserted obliquely at the base of the calyx tube on a stipe, with a fleshy incurved style tipped by an obtuse stigma. Flowers are pollinated by long-tongued bees such as blueberry bees and carpenter bees; short-tongued bees cannot reach the nectaries. The fruit is a flattened, dry, brown pea-like pod 5โ10 cm (2โ4 in, or 2 and a half to 3 inches) long. It is slightly stipitate, unequally oblong, acute at both ends, compressed, tipped with style remnants, straight on the upper edge and curved on the lower edge. Pods are rose-colored when full grown by mid-summer, mature to brown between August and October, and fall in early winter. Pods contain 10 to 12 flat, elliptical, chestnut-brown seeds 6 mm (1โ4 in, one-fourth of an inch) long. Cotyledons are oval and flat. The wood is dark reddish brown, heavy, hard, coarse-grained, and not strong; it has a specific gravity of 0.6363, and weighs 39.65 lbs per cubic foot. Cercis canadensis is widely cultivated in parks and gardens, with many cultivars available. The cultivars 'Forest Pansy' and 'Ruby Falls' hold the Royal Horticultural Society's Award of Garden Merit (confirmed in 2017); both are grown for their showy purple leaves that turn brilliant shades of red and orange in autumn, and 'Ruby Falls' is a weeping cultivar. In the wild, eastern redbud is a common native understory tree found in mixed forests and hedgerows. It is widely planted as a landscape ornamental tree. In the United States, it is difficult to grow this tree farther west into the arid regions west of western Kansas and Colorado, due to insufficient rainfall. The tree has been grown successfully in Columbus, Wisconsin, and the local selection, known as the "Columbus strain", is used as a seed source for nurseries. To germinate seeds, soak them in boiled (99 ยฐC) water for one minute then sow in a pot; the seeds themselves should not be boiled. Cercis canadensis var. mexicana tolerates high salinity levels, allowing it to grow more successfully in areas of the southwestern United States. The flowers of eastern redbud can be eaten fresh or fried. In parts of southern Appalachia, green twigs are used as a seasoning for wild game including venison and opossum, so the tree is sometimes called spicewood in these mountain areas. Native Americans consume the flowers raw or boiled, and eat roasted seeds. Nutritional analysis of edible parts of eastern redbud found that flower extracts contain anthocyanins, developing green seeds contain proanthocyanidin, and seeds contain linolenic, ฮฑ-linolenic, oleic, and palmitic acids.
