Edward F. Gilman, Dennis G. Watson, Ryan W. Klein, Andrew K. Koeser, Deborah R. Hilbert, and Drew C. McLean
Introduction
Black tupelo is a hardwood tree which grows to 75 feet tall, has a medium growth rate, pyramidal shape with horizontal branches growing from a typically straight trunk. But the shape of the crown varies from tree to tree and, unfortunately, this is looked upon by some architects as undesirable. As the tree grows to 10 and 15-years-old, crown form becomes more uniform among trees. Lower branches droop with age and will need to be removed if used as a street tree. Growth habit is similar to pin oak, a tree which many people are familiar with. Providing a brilliant display of red to deep purple foliage in the fall, black tupelo surprises most people since it does not particularly stand out in the landscape until then. The small, blue fruits may be considered a litter nuisance in urban/suburban plantings but are quite popular with many birds and mammals, and they wash away quickly.
Figure 1. Full Form - Nyssa sylvatica: black tupelo Credit: UF/IFAS
General Information
Scientific name: Nyssa sylvatica
Pronunciation: NISS-uh sill-VAT-ih-kuh
Common name(s): black tupelo, blackgum, sourgum
Family: Nyssaceae
USDA hardiness zones: 4B through 9B (Figure 2)
Origin: native to the east half of the United States, extreme southern Ontario, and central and southern Mexico
UF/IFAS Invasive Assessment Status: native
Uses: reclamation; specimen; street without sidewalk; shade; parking lot island 100-200 sq ft; parking lot island > 200 sq ft; sidewalk cutout (tree pit); tree lawn 4-6 feet wide; tree lawn > 6 ft wide; highway median
Figure 2.
Description
Height: 65 to 75 feet
Spread: 25 to 35 feet
Crown uniformity: symmetrical
Crown shape: pyramidal, oval
Crown density: moderate
Growth rate: slow
Texture: medium
Foliage
Leaf arrangement: alternate
Leaf type: simple
Leaf margin: entire
Leaf shape: elliptic (oval), oblong
Leaf venation: pinnate
Leaf type and persistence: deciduous
Leaf blade length: 2 to 6 inches
Leaf color: dark green and shiny on top, paler green underneath; develops purplish spots
Fall color: orange, red, and deep purple
Fall characteristic: showy
Figure 3. Leaf - Nyssa sylvatica: black tupelo Credit: UF/IFAS
Flower
Flower color: greenish yellow
Flower characteristics: not showy; emerges in clusters on a small stalk at leaf axils
Flowering: spring
Figure 5. Flower, Male - Nyssa sylvatica: black tupelo Credit: UF/IFAS
Fruit
Fruit shape: oblong
Fruit length: ¼ to ½ inch
Fruit covering: fleshy drupe
Fruit color: blue-black
Fruit characteristics: attracts birds; not showy; fruit/leaves a litter problem
Fruiting: ripens in late summer and early fall
Trunk and Branches
Trunk/branches: branches droop; not showy; typically one trunk; no thorns
Bark: dark gray, brown, brown black; irregularly and shallowly furrowed; becoming blocky with age
Pruning requirement: little required
Breakage: resistant
Current year twig color: gray, brown
Current year twig thickness: thin, medium
Wood specific gravity: 0.50
Figure 6. Bark, Young - Nyssa sylvatica: black tupelo Credit: UF/IFAS
Soil tolerances: clay; sand; loam; acidic; wet to well-drained
Drought tolerance: high
Aerosol salt tolerance: moderate
Other
Roots: not a problem
Winter interest: yes
Outstanding tree: yes
Ozone sensitivity: tolerant
Verticillium wilt susceptibility: susceptible
Pest resistance: free of serious pests and diseases
Use and Management
Black tupelo prefers a moist, slightly acid soil. Larger specimens may be difficult to transplant from deep, well-drained field soil because of its deep roots and should only be transplanted from the field in the spring. Therefore, it is usually seen growing in containers at the nursery. Little pruning is required to form a well-structured tree since the trunk stays straight and branches usually grow at wide angles with the trunk. Black tupelo makes a good street or parking lot tree for suburban neighborhoods, possibly for downtown areas. It should be used more often for this purpose but will benefit from occasional irrigation in droughts. Does amazingly well in wet, compacted soils typical of many urban areas with highly disturbed clay soil. It is also somewhat salt-tolerant for planting along the shore.
Black tupelo is rarely attacked by pests, and when it is they are rarely serious enough to warrant control.
Nyssa sylvatica var. sylvatica grows on moist sites; var. aquatica has a buttressed and swollen trunk base and grows in swamps. Nyssa bicolor is very similar and often confused with Nyssa sylvatica.
Pests
Scales, including Sourgum scale, can be controlled with horticultural oil.
Forest tent caterpillar can defoliate the tree in the spring. Unless defoliation is extensive in two or more successive years, control is not needed.
Diseases
Several fungi cause cankers on black tupelo. As the cankers enlarge the infected stems die back. Trunk cankers cause tree dieback. Prune out infected branches and keep trees healthy.
Leaf spots cause purplish blotches on the upper leaf surface. Rake up and destroy infected leaves in the fall to reduce the disease potential for the following year, if you wish.
Recently a large number of trees have been discovered dying in the mountains of North Carolina, Tennessee, Virginia, and Georgia. The causal agent is unknown but symptoms include leaf spots, branch cankers, leaves dying and hanging on the tree, and leaf blotches.
Reference
Koeser, A. K., Hasing, G., Friedman, M. H., and Irving, R. B. 2015. Trees: North & Central Florida. University of Florida Institute of Food and Agricultural Sciences.
