T r e e s  o f  N o r t h  C a r o l i n a

Prunus L. (Rosaceae)

A genus of about 200 species of trees and shrubs; nearly cosmopolitan, but especially in north temperate regions.

Fourteen species reach tree size in North Carolina, eight of which are considered native to the state.

Keys to Prunus in North Carolina

1. Flowers in elongate racemes of (12-) 20-many flowers...Key A, Black-cherries

1. Flowers solitary, in fascicles, in umbellate or corymbose inflorescences, or in short racemes (P. mahaleb) of 1-12 flowers...2.

2. Flowers and fruit sessile or on a pedicel < 2 mm long...*P. persica, Peach

2. Flowers and fruit pedicellate, the pedicel > 4 mm long; fruit glabrous, ovary glabrous or pubescent initially...3.

3. Stones globose, not 2-edged; sepals hairy or not; inflorescences subtended by leafy bracts arising from the same bud as the flowers (except P. pensylvanica)...Key B, Cherries

3. Stones somewhat to strongly flattened, 2-edged; sepals hairy on the upper surface; inflorescences without leafy bracts arising from the same bud as the flower...Key C, Plums

Key A - Black-cherries [subg. Padus]

1. Leaves evergreen, entire or serrate with few or rather many (but widely spaced) prominent teeth; petioles lacking 2 glands near junction with leaf blade; [native in maritime situations from e. NC southward, but cultivated and escaped inland]...P. caroliniana (Carolina laurel cherry)

1. Leaves deciduous, regularly and rather finely toothed; petioles with 2 glands near the junction with the leaf blade; [collectively widespread, native and alien]...2.

2. Leaf teeth triangular, pointing outwards; leaves dull above; sepals conspicuously glandular-eroded on the margin, not persistent on the fruit; colonial, thicket-forming shrub from rhizomes; [montane in our area]…P. virginiana (Choke cherry)

2. Leaf teeth curved, appressed; leaves shiny above; sepals entire or slightly glandular-eroded on the margin, persistent on the fruit; small to large tree, not clonal; [collectively widespread]...P. serotina (Black-cherry)

Key B - Cherries [subg. Cerasus and Lithocerasus]

1. Plant a shrub or small tree, to 1.5 (-3) m tall; inflorescences of 1-2 flowers; [exotic, persistent from cultivation; subg. Lithocerasus]...*P. glandulosa (Dwarf flowering almond)

1. Plants trees, well over 3 m tall when mature; [subg. Cerasus]...2.

2. Petals 4-7.5 mm long; fruit < 1 cm in diameter...3.

3. Inflorescence with a central axis, thus nearly or actually racemose; fruit blackish; leaves 1-1.5× as long as wide; [exotic tree]...*P. mahaleb (Mahaleb cherry)

3. Inflorescence umbellate to corymbose, the central axis absent or poorly developed; fruit red; leaves 2-5× as long as wide; [native tree]...P. pensylvanica (Fire cherry)

2. Petals 9-15 mm long; fruit 1.3-2.5 cm in diameter...4.

4. Leaves 7-15 cm long, persistently hairy beneath, at least along the midrib and veins; pair of petiolar glands on the petiole near the blade; fruit sweet when ripe...*P. avium (Sweet cherry)

4. Leaves 4-8 cm long, glabrous beneath once fully-expanded; pair of petiolar glands on the base of the leaf blade; fruit sour when ripe...*P. cerasus (Sour cherry)

Key C - Plums [subg. Prunus]

1. Leaf teeth gland-tipped (or with a scar where the gland has fallen); sepals with marginal glands (except P. angustifolia); fruit yellow to red when ripe...2.

2. Leaves 3-6 cm long, often folded longitudinally; sepals lacking marginal glands...P. angustifolia (Chickasaw plum)

2. Leaves 5-13 cm long, not folded; sepals with marginal glands...*P. munsoniana (Munson plum)

1. Leaf teeth glandless; sepals without marginal glands; fruit yellow, red, purple-red, purple, or black when ripe...3.

3. Petals 10-15 mm long; leaves 6-10 cm long, acuminate; fruit 2-2.5 cm long, red or yellow...P. americana (American wild plum)

3. Petals 4-9 mm long; leaves 4-8 cm long, obtuse, acute, or slightly acuminate; fruit 1.0-1.5 cm long, dark purple, black (rarely yellow or red)...4.

4. Plants often suckering and forming thickets, less often single plants, shrubs or less often trees; leaf apices short acuminate (to merely acute); pedicels usually < 10 mm long; [Mt and Pd from nw. NC northward]...P. alleghaniensis (Alleghany plum)

4. Plants usually not suckering, often single plants but sometimes in small colonies, generally trees; leaf apices mostly acute; pedicels usually > 10 mm long; [Mt, Pd, CP]...P. umbellata (Hog plum)