Photinia |
Photinia serratifolia |
|||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
chokeberry, photinia, redtip |
Chinese photinia, Chinese photinia or hawthorn, photinia, Taiwanese photinia |
|||||||||||||
Habit | Shrubs or trees, 10–120 dm. | Plants 40–60(–120) dm. | ||||||||||||
Stems | 1–15+, erect; bark gray; short shoots absent; unarmed; glabrous. |
|||||||||||||
Leaves | persistent or deciduous, cauline, simple; stipules deciduous, free, usually subulate, margins dentate or entire; petiole present; blade oblong to elliptic or elliptic-obovate, 3–20 cm, coriaceous or herbaceous, margins flat, serrate to serrulate, rarely entire, venation pinnate, surfaces glabrous at least at maturity. |
persistent; petiole 20–40 mm, villous adaxially when young, glabrescent; blade narrowly elliptic to oblong, obovate-elliptic, or narrowly obovate, (6–)9–20 × 3–6.5 cm, coriaceous, base rounded or broadly cuneate, margins sharply serrate to rarely inconspicuously toothed or entire, lateral veins 20–30 pairs, apex acuminate, abaxial surfaces slightly villous along veins when young, quickly glabrescent. |
||||||||||||
Inflorescences | terminal, erect or pendulous in fruit, 150–300-flowered, corymbose (compound-corymboid) or subumbellate [compound-racemose], glabrous or glabrate; bracts present; bracteoles present. |
10–18 cm diam. |
||||||||||||
Pedicels | present. |
without lenticels. |
||||||||||||
Flowers | perianth and androecium perigynous, 6–12[–15] mm diam.; hypanthium cupulate to campanulate or cylindric, 1–2 mm, usually glabrous; sepals 5, incurved, triangular; petals 5, white, oblong to elliptic, obovate, or orbiculate to suborbiculate, base clawed; stamens (16–)20(–25), ± as long as or slightly shorter than petals; carpels (1 or)2–5, connate, adnate to proximal 1/2–1/3 of hypanthium, free apically, glabrous or apically pilose, styles [1 or]2–4[or 5], terminal, distinct or ± basally connate, stigmas truncate or capitate; ovules 1 or 2. |
6–8 mm diam.; petals suborbiculate, 3–4 mm, glabrous or villous. |
||||||||||||
Fruits | pomes, red or black, globose to ovoid or ellipsoid, sometimes apically depressed, 4–8[–12] mm, usually glabrous; somewhat fleshy; carpels capped by hard-shelled dome that rises above hypanthium; hypanthium persistent; sepals persistent, spreading (adnate to hypanthium); carpels cartilaginous; styles deciduous. |
|||||||||||||
Seeds | (1 or)2 per carpel. |
|||||||||||||
x | = 17. |
|||||||||||||
Photinia |
Photinia serratifolia |
|||||||||||||
Phenology | Flowering late Mar–Apr. | |||||||||||||
Habitat | Fencerows, thickets, disturbed sites | |||||||||||||
Elevation | 20–200 m (100–700 ft) | |||||||||||||
Distribution |
Mexico; Central America; Asia [Introduced in North America; introduced also in Europe, Pacific Islands (Hawaii, New Zealand), Australia] |
AL; GA; LA; MS; TX; Asia [Introduced in North America]
|
||||||||||||
Discussion | Species 40–60 (4 in the flora). Photinia is widely introduced in cultivation and naturalizing, at least in the continental United States. Species are native mostly to warm temperate Asia, from the Himalayas east to Japan and south to India and Thailand. Molecular data suggest that Heteromeles originated through hybridization, with a species of Photinia as pollen parent (Guo W. et al. 2011). Five species from Mexico and Central America were included within Photinia by J. B. Phipps (1992) and molecular evidence corroborates their placement there (Guo W. et al. 2011). The Asian Stranvaesia has sometimes been treated as distinct from Photinia, but botanists have noted the apparent artificiality of a primary character used to differentiate the two genera, namely an endocarp dehiscent in Stranvaesia, indehiscent in Photinia (C. Kalkman 1973; J. B. Phipps et al. 1991b; K. R. Robertson et al. 1991; J. R. Rohrer et al. 1991, 1994). Kalkman observed that the putative dehiscence of Stranvaesia carpels is an artifact of specimen preparation. Rohrer et al. (1991, 1994) found that Photinia and Stranvaesia do not differ in connation of the carpels or in the adnation of the carpels to the hypanthium. Molecular phylogenetic analyses (Guo W. et al. 2011) show that the Stranvaesia species have arisen within the cladistic topology of Photinia. The primarily eastern North American genus Aronia (for example, A. floribunda, A. melanocarpa) has been included in Photinia in some classifications (K. R. Robertson et al. 1991) but is here treated as distinct. Many species of Photinia are ornamental trees and shrubs with large lustrous leaves and masses of white flowers in the spring followed by red fruits in the fall. The flowers last about two weeks and commonly have an unpleasant smell. The wood is hard and heavy and has been used for furniture and small articles such as axe handles. Photinias have been widely and abundantly planted for hedging in the southeastern United States. The rapid spread since about the mid 1980s of a fungal leaf spot, Entomosporium maculatum, has been lethal to many such hedges. Photinia ×fraseri ('red tip'; see under 2. P. serratifolia) and P. glabra are severely affected; P. serratifolia is said to be partially resistant. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Four varieties of Photinia serratifolia are recorded in China; var. serratifolia occurs in the flora area and has leaf margins prominently serrate, entire only near the base (versus entire to shallowly and inconspicuously serrate in other varieties). Cultivars have been developed, however, differing in growth form, coloration, and leaf margins, and a formal identification to variety is problematic. Chinese photinia can grow larger than P. ×fraseri (‘red tip’) or Japanese photinia, and flowers appear before those of either. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
||||||||||||
Key |
|
|||||||||||||
Source | FNA vol. 9, p. 488. | FNA vol. 9, p. 490. | ||||||||||||
Parent taxa | ||||||||||||||
Sibling taxa | ||||||||||||||
Subordinate taxa | ||||||||||||||
Synonyms | Stranvaesia | Crataegus serratifolia | ||||||||||||
Name authority | Lindley: Bot. Reg. 6: plate 491. (1820) | (Desfontaines) Kalkman: Blumea 21: 424. (1973) | ||||||||||||
Web links |