Black cherry (Prunus serotina) is a large native deciduous tree in the rose family, ranging across eastern North America from Nova Scotia to Florida and west into the central plains. It is among the most ecologically productive native trees on the continent: the fruit supports more than 40 bird species and dozens of mammals, and the foliage hosts several hundred Lepidoptera species, including large silk moths and the eastern tiger swallowtail.
The tree is fast-growing and colonizes disturbed edges, roadsides, and old fields readily via bird-dispersed seeds. Mature bark breaks into distinctive dark, upturned plate-like scales and smells faintly of almond when scratched. Wilted or frost-damaged leaves release hydrogen cyanide and are acutely toxic to livestock; remove fallen limbs from pastures promptly. Volunteers establish far from the parent tree and should be managed early. The tree performs best in slightly acidic, well-drained loam but tolerates clay and sandy soils. Mulching the root zone suppresses competition and improves establishment on poor sites. Prefers a slightly acidic pH in the 5.5–6.5 range.
Wild cherry bark was a standard ingredient in commercial antitussive preparations well into the mid-20th century and remains in herbal use today. Ripe fruit, though small and astringent eaten raw, is used for jams, jellies, wine, and cherry-infused spirits. Bark and wood yield a warm reddish-brown hardwood that is among the most commercially valuable American timbers, used for furniture, cabinetry, and instrument making.
Black Knot
Hard, elongated galls form on stems and branches, starting olive-green and soft before turning black, corky, and woody. Galls girdle stems, killing all growth beyond the infection point. Severely infected plants develop multiple swollen knobs throughout the canopy.
Prune infected wood at least 8 inches below any visible gall during dormancy; sterilize pruning tools between each cut with 70% isopropyl alcohol or 10% bleach solution. Remove and destroy all pruned material — do not compost. In orchards or high-pressure sites, apply a copper-based or lime-sulfur fungicide at bud swell and again 10–14 days later. Remove nearby wild Prunus hosts, which serve as inoculum reservoirs.
Brown Rot
Blossoms turn brown and cling to the twig rather than dropping (blossom blight). Developing or ripe fruit shows soft, rapidly expanding brown lesions covered in distinctive ash-gray powdery spore tufts. Infected fruit shrivels into hard mummies that persist on branches through winter.
Remove and destroy mummified fruit from branches and the ground at pruning time. Apply sulfur or a registered fungicide at full bloom and again 2–3 weeks before harvest during wet seasons. Thin fruit to reduce canopy density and direct fruit-to-fruit contact, which speeds spread.
Bacterial Spot
Small water-soaked angular lesions on leaves that turn dark brown and drop out, leaving ragged shot-holes. Sunken, water-soaked dark spots on fruit skin that can crack and invite secondary rots. Twig cankers with gummy amber exudate on young wood.
Apply copper-based bactericide beginning at petal fall and repeat on a 10–14 day schedule through early summer. Avoid overhead irrigation. Prune for open canopy airflow. Remove and destroy infected shoots during dormant pruning. Elberta has moderate susceptibility; consider planting resistant cultivars in high-pressure sites.
Shot Hole Disease
Small reddish-purple spots on leaves that dry out and drop, leaving ragged holes across the leaf surface. Severe infections cause early defoliation. Dark sunken lesions may appear on young stems.
Remove and dispose of infected leaves and stems. Avoid overhead irrigation and wetting foliage. Apply a copper-based fungicide in fall just before seasonal rains begin; repeat in early spring if the previous season was severe. Ensure good air circulation through selective pruning.
Powdery mildew
White or grey powdery coating on leaves — usually starting on older growth in humid conditions or when nights cool.
Improve air circulation by thinning plants. Apply neem oil or potassium bicarbonate spray at first sign. Avoid overhead watering.
Cytospora Canker
White or blue-white pitch masses ooze from bark on lower branches and the trunk. Affected branches die back progressively from the tip inward; bark beneath the resin is discolored brown and may have a resinous, sunken appearance.
Prune infected branches well below the canker margin into healthy wood and destroy all cuttings. Sterilize pruning tools with 70% isopropyl alcohol between each cut. No effective fungicide is available; prevent recurrence by avoiding drought stress, soil compaction, and mechanical bark injury.
Fungal leaf spot
Brown or purplish spots on the leaves, often ringed with a yellow halo, that spread and merge in warm, humid, or wet weather; heavily spotted leaves yellow and drop early.
Pick off spotted leaves and clear fallen debris to remove overwintering spores. Improve air circulation by thinning, and water at the base so foliage dries quickly. If it persists, apply a copper- or sulfur-based fungicide at the first sign.
Armillaria Root Rot
Thinning, yellowing canopy with progressive dieback; white, fan-shaped mycelial mats visible beneath bark at or just below the soil line; honey-colored mushroom clusters appearing at the trunk base or on surface roots in autumn.
No chemical cure exists. Improve drainage and avoid any injury to roots or trunk. Remove severely infected trees along with as much root material as possible. Do not replant susceptible species in the same spot.