Species

• Alternate-leaf dogwood, pagoda dogwood
• Cornus alternifolia L.f.
• Cornaceae, the dogwood family
• Confidence high, on zoomed photos plus a range check. See "Verification round 2."

Evidence (tied to photos)

• Dogwood venation (IMG_4980, IMG_4990, IMG_4991): 5–6 pairs of secondary veins arc forward and run nearly parallel to the entire margin toward the tip, deeply impressed into the blade for a quilted, rugose look. This camptodromous dogwood arc is diagnostic for Cornus.
• Fruit (IMG_4981): a branched cyme with orange-red coral pedicels carrying round drupes ripening from green through pink and purple to bluish-black, several already blue-black. Bluish-black drupes on orange-red stalks is the textbook signature of C. alternifolia, and it separates the species from the pale-blue, greenish-to-reddish-stalked fruit of silky dogwood.
• Habit and phyllotaxy (IMG_4980, IMG_4983): leaves crowded and whorled-looking at the ends of the twigs, the false whorl of alternate-leaf dogwood. The leaves are truly alternate, just clustered at the branch tips.
• Leaf underside (IMG_4990, IMG_4991): paler, slightly glaucous, with brownish tissue near the petiole. Consistent with C. alternifolia.
• Twig (IMG_4983, IMG_4992): slender woody twig, gray-brown with lenticels and raised leaf scars, green current-season growth at the tip.

Verification round 2 (zoomed crops + range check)

I re-examined full-resolution crops of the originals to settle the one open question, leaf and branch arrangement, because C. alternifolia is the only alternate-leaved dogwood in the eastern U.S. Every other Cornus here is opposite, so that single character is decisive.

• Alternate, sympodial branching (zoom of IMG_4992): the woody twig branches in a zig-zag, one-side-at-a-time pattern, with a lateral diverging from a node and no matching branch opposite it. Opposite-leaved dogwoods (amomum, florida, foemina) branch in symmetric pairs. Alternate branching means C. alternifolia.
• Terminal false whorl (zoom of IMG_4983): leaves radiate from a crowded terminal cluster with very short internodes rather than as separated opposite pairs, the "nearly whorled" look the NC State herbarium uses for this species.
• Coral-red pedicels with uniform blue-black drupes (zoom of IMG_4981): the cyme is green at the base grading into coral-red branchlets, carrying drupes that are evenly blue-black with no white or blotchy marbling. Silky dogwood drupes are typically paler blue and often white-marbled, so this points away from amomum too.
• Underside pale and glaucous rather than rusty (zoom of IMG_4990/4991): leaf undersides are pale and slightly waxy with no dense rusty-brown silky pubescence. Silky dogwood has conspicuous rusty appressed hairs beneath. Another strike against amomum.
• Leaf-shape range confirmed: flora descriptions give C. alternifolia leaves as "narrowly to broadly ovate or obovate, cuneate to rounded base, 4–12 cm," so the broad rounded rugose leaves in IMG_4990/4991 and the more elongate ones in IMG_4980 are both normal for this species. That resolves the shape inconsistency that bothered me earlier.
• Range confirmed: NC State herbarium lists C. alternifolia as "Common" in the NC Mountains in moist forests. Polk County and the Blue Ridge escarpment are squarely within range.

Net: the alternate branching alone is diagnostic, and every other character (fruit, pedicel color, ripening date, venation, underside, habitat, range) agrees. Confidence high. If I'm curious next visit, a lower twig on the parent plant will show single, spiraled leaf attachment.

Look-alikes ruled out

The collected material shows alternate branching, and C. alternifolia is the only alternate-leaved dogwood in the eastern U.S., which alone eliminates every opposite-leaved Cornus below. Each is cross-checked on a second character anyway.

• Silky dogwood (Cornus amomum), the main alternative. Opposite leaves, fruit ripening white then pale blue on greenish-to-reddish stalks, and later (Aug–Sep). A wetland and streambank thicket shrub. Ruled out by the orange-red pedicels and bluish-black fruit already ripe in mid-July, plus the tip-clustered foliage.
• Flowering dogwood (Cornus florida): red fruit, opposite leaves. Ruled out by fruit color and by the branched cyme; florida has clustered drupes and no showy red cyme.
• Gray dogwood (Cornus racemosa) and redosier (C. sericea): white fruit. Ruled out by the blue-black drupes.
• Stiff or swamp dogwood (Cornus foemina): has blue drupes on reddish cymes too, but is opposite-leaved, narrower-leaved, and mainly a Coastal Plain and Piedmont wet species, uncommon in mountain coves. Ruled out by alternate branching, broad rugose leaves, and the mountain-cove site.
• Viburnum nudum / witherod (V. cassinoides): also has multi-colored cymes of blue-black drupes in wet ground, and I seriously considered it. Ruled out on venation. Viburnum has straighter pinnate veins running into the margin, whereas these leaves show veins bending to parallel the margin (the dogwood arc), and the venation is deeply impressed.

Habitat check

Excellent fit. C. alternifolia in NC is "primarily in the Mountains, rare in the Piedmont," growing in cool, moist, rich acidic woods, coves, and stream banks. That is the Saluda escarpment collection setting exactly: <50 m from a stream, low cove-like valley. It likes cool root zones and humus-rich soils, which the site provides.

Seed propagation

• Maturity window: fruit ripens bluish-black by mid-summer, so the mid-July collection is well-timed. For once this is not an immature-seed problem. The already blue-black drupes in IMG_4981 hold viable seed; the green and pink ones are still developing and are best left or discarded.
• Clean: sort out the fully blue-black fruits. Soften the pulp in water a day or two, then mash and rinse, floating off pulp and empty stones. Each drupe has one hard stony pit. A short soak in very dilute bleach helps remove pulp and reduce mold. Don't let cleaned seed dry out if I can sow promptly.
• Dormancy: physiological embryo dormancy inside a hard endocarp. Two reliable routes:
  1. Warm then cold: 60 days warm and moist (68–86 °F), then 60–90 days cold and moist (~34–41 °F). Sowing fresh right now and leaving flats outdoors over winter lets nature run the sequence.
  2. Cold only: ~90–120 days cold, moist stratification at ~41 °F is usually enough, then sow in spring at 70–85 °F.
• Germination timeline: after stratification, emergence in roughly 3 months (about 13–14 weeks) at warm germinating temperatures. Expect the usual dogwood pattern where some seed sits until a second spring. Don't discard flats after one season.

Vegetative propagation

• Softwood or semi-hardwood tip cuttings, the best odds. Take them in summer (now is in range) from the current season's growth. Dip in IBA rooting hormone (~6,000 ppm K-IBA liquid, or up to ~16,000 ppm IBA talc), stick under mist or fog, roots in ~6–8 weeks, realistically up to ~60% success. Overwinter the rooted cuttings with minimal disturbance; first-year rooted dogwoods are fragile.
• Hardwood cuttings: pagoda dogwood is one of the easier dogwoods, and dormant hardwood cuttings will sometimes root in a bucket of damp sand over winter.
• Layering: low horizontal branches, and this species' pagoda tiers sit low, can be soil-layered and left a season to root. Low-effort backup.

Grow-out in the NC Piedmont

• Hardiness: C. alternifolia is rated ~USDA 3–7b and struggles in zone 8 and hot humid summers. Much of the NC Piedmont is 7b–8a, warmer and with heavier clay than the Saluda escarpment collection site, so this is the least Piedmont-friendly plant in the collection so far. Plan for the microclimate rather than the average.
• Site: a cool, shaded to part-shade spot with morning sun and afternoon shade, ideally a north or east-facing wooded edge. Avoid hot, open, reflected-heat locations.
• Soil: acidic, rich, well-drained but consistently moist, high organic matter. Amend heavy clay with compost and mulch heavily to keep the root zone cool and damp. Water through Piedmont summer droughts.
• Cautions: shallow-rooted and transplant-sensitive, so move seedlings young and handle roots gently. Prone to golden canker (Cryptodiaporthe) stress in hot, dry, sunny sites, another reason to keep it cool and moist.

Next step

1. From IMG_4981, pick out the blue-black drupes only, clean off the pulp, and sow the stones fresh right now in a deep pot of gritty humusy mix. Leave it outdoors, shaded, and never dry through fall and winter for the natural warm-then-cold cycle. Watch for germination next spring, and again the spring after.
2. Hedge with cuttings. If I can get back to the parent plant, or use any attached green tips I collected, take softwood tip cuttings with hormone and mist this summer.
3. Confirm the ID next visit: check a lower twig for alternate (single, spiraled) leaf attachment versus opposite pairs. Alternate confirms C. alternifolia.
4. Reserve a cool, shaded, moisture-retentive corner of the Piedmont garden for it. This is a mountain species being pushed toward the warm edge of its range.

Sources

• NC State Extension — Cornus alternifolia (Alternate-leaf Dogwood)
• NC State Extension — Cornus amomum (Silky Dogwood)
• Will Cook, Carolina Nature — Alternate-leaved Dogwood (Cornus alternifolia)
• Illinois Wildflowers — Alternate-leaved Dogwood
• Lady Bird Johnson Wildflower Center — Cornus alternifolia
• Virginia Tech Dendrology — Cornus alternifolia fact sheet
• NC State Herbarium (TNC) — Cornus key & NC distribution
• Trees and Shrubs Online — Cornus alternifolia (leaf dimensions/description)
• UF/IFAS Landscape Plant Propagation — Cornus alternifolia