Nyssa sylvatica, N. biflora, blackgum, swamp tupelo
Coladonato, Milo 1992. Nyssa spp: N. sylvatica, N. biflora, tupelos: blackgum, swamp tupelo. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://research.fs.usda.gov/feis/species-reviews/nysspp
| Abbreviation | Common Name | Scientific Name | Classification | Status |
|---|---|---|---|---|
| Plants | ||||
| NYSBIF | swamp tupelo | Nyssa biflora | Life Form: Plants/Tree Kingdom: Plantae Class: Dicot Order: Cornales Family: Cornaceae Genus: Nyssa | Fed. Protected: No Nativity: Native Invasiveness: Noninvasive |
| NYSSYL | blackgum | Nyssa sylvatica | Life Form: Plants/Tree Order: Cornales Family: Cornaceae Genus: Nyssa | Fed. Protected: No Nativity: Native Invasiveness: Noninvasive |
Taxonomy
This review provides information on two closely related species in the family Cornaceae:
- Nyssa sylvatica Marsh [39,51,56,58], blackgum
- Nyssa biflora Walter [51,57], swamp tupelo
Blackgum occurs on light-textured soils of uplands and stream bottoms, and swamp tupelo occurs on heavy organic or clay soils of wet bottomlands [44].
Synonyms
- For swamp tupelo: Nyssa sylvatica var. biflora (Walter) Sarg.
Other Common Names
for blackgum: black tupelo, swamp blackgum
for swamp tupelo: sourgum, pepperidge, tupelo, tupelo-gum, yellow gum
General Distribution
Distributions of blackgum (left) and swamp tupelo (right)
Blackgum grows from southern Ontario and southwestern Maine south to central Florida. It is local in central and southern Mexico [19,26,44].
Swamp tupelo is most common on the Coastal Plain swamps and estuaries from Maryland and southeastern Virginia south to southern Florida. It grows on the east side of the Mississippi River to East Texas [19,26,44].
States and Provinces
- United States: AL AR CT DE FL GA IL IN KY LA ME MD MA MI MS MO NH NJ NY NC OH OK PA RI SC TN TX VT VA WV
- Canada: ON
- Mexico
Site Characteristics
Swamp tupelo, Florida.
Blackgum is adapted to a wide variety of sites, from the creek bottoms of the southern Coastal Plain to altitudes of 3,000 feet (915 m) in North Carolina. Blackgum will tolerate brief spring flooding on alluvial sites and is common on the relatively dry upper and middle slopes in the Appalachian Mountains. On the drier uplands, blackgum will survive but with a slower growth rate [4,26]. Swamp tupelo is found in and on the banks of swamps, ponds, and estuaries of the Coastal Plain, and in low coves and seepages which remain wet year-round [1,19,44].
Common tree associates of both species are: black cherry (Prunus serotina), dogwood (Cornus florida), hickory (Carya spp.), oak (Quercus spp.), hophornbeam (Ostrya virginiana), yaupon (Ilex vomitoria), swamp cyrilla (Cyrilla racemiflora), and redbay (Persea borbonia) [13,17,42,43,45].
Plant Communities
Kologiski has included blackgum as an indicator or dominant in the following community type classification [33]:
| Location | Classification | Authority |
|---|---|---|
| Southeastern North Carolina | general veg. cts | Kologiski 1977 |
Botanical Description
Blackgum, Massachusetts.
Blackgum is a medium- to large-sized, native, deciduous tree, frequently 60 to 80 feet high (18-24 m) [22,31]. In the forest it typically has a dense foliage with a conical crown on an erect trunk which extends continuously into the top. The simple, alternate leaves are leathery, and densely clustered at the branchlets. The small greenish white flowers are borne singly or in capitate clusters. The bark is reddish brown and broken into deep irregular ridges and diamond-shaped plates. On old trunks, the bark may be an inch (2.5 cm) or more thick [12,15].
Swamp tupelo develops a long taproot and a swollen base [44].
Raunkiaer Life Form (Raunkiaer 1934)
- Phanerophyte
Seasonal Development
Blackgum and swamp tupelo flower in the spring when the leaves are nearly grown. Fruits develop over the spring and summer and ripen early to late fall depending on latitude and climate. General timing of flowering, and fruit ripening and dispersal for the two species is as follows [10,19,26]:
| Species | Flowering | Fruit ripening | Fruit dispersal |
|---|---|---|---|
| Blackgum | April-June | September-October | September-November |
| Swamp tupelo | late March-June | August-October | September-December |
Regeneration Processes
Seed production and dispersal
Seed production in blackgum is highly variable while swamp tupelo is a prolific seed producer [10,23]. Viability of swamp tupelo seed, which averages 60 percent, increases as the season progresses [44]. The principal dissemination agents are gravity and birds [41]. Birds consume the fleshy fruits and seed are passed through the digestive tract [44,48]. The fruits are not persistent and fall shortly after ripening in late summer or fall. Seeds not dispersed by animals generally fall to the ground near the tree and remain dormant in the litter or are transported by water [14,48].
Seedling development
Under natural conditions, seed overwinters on cool, damp soil and germinates the following spring. Both varieties appear to require nearly full sunlight for optimum early growth. Black tupelo, however, will tolerate more overhead competition and can exist on unfavorable sites. Swamp tupelo is much less adaptable [14,23,44].
Vegetative reproduction
Both blackgum and swamp tupelo will sprout from the stump following disturbance. Smaller blackgum stumps sprout readily while larger stumps sprout occasionally. Sprouts arise from suppressed buds and are concentrated near the top of the stump [32,44].
Stump sprouts can produce seeds at 2 years of age. Thus, if the seed crop fails or unfavorable weather conditions prevent a good crop of seedlings from becoming established, sprouts can provide a seed source [32,44].
Successional Status
Blackgum is usually found with a mixture of other species. It is classed as tolerant of shade and rarely attains overstory dominance but is usually grows in the intermediate crown class on most sites. Intermediate blackgum stems respond favorably to release from overtopping vegetation. Seedlings grow slowly under a fully stocked stand. When the canopy is removed, about 25 percent or more can be expected to respond with relatively rapid height growth. At the time of disturbance large numbers of new seedlings can become established. Swamp tupelo is classed as intolerant of shade and will not develop unless released [2,6,20,44].
Immediate Fire Effects
The effects of fire on blackgum depends on the size of the individual and severity of fire. Most fires typically top-kill blackgum. However, hot fires during dry periods can cause mortality and deformity [5,55].
On the Atlantic Coastal Plain, prescribed summer fires caused some top-kill in blackgum up to 4 inches d.b.h (10 cm). Top-kill averaged 50 percent for trees 2 inches (5 cm) d.b.h. [11].
Fire wounds can serve as entry points for various heart rot fungi [47].
Postfire Regeneration Strategy (Stickney 1989)
- survivor species; on-site surviving root crown or caudex
- off-site colonizer; seed carried by animals or water; postfire yr 1&2
Fire Adaptations
Blackgum is well adapted to fire. Older trees have thick bark and relatively high moisture content [48]. Swamp tupelo sites are usually quite wet and fire is only a factor during periods of extended drought [5,44]. Although aboveground portions of young blackgum are top-killed by fire, the species typically survives by sprouting from the root crown or caudex [32,53].
Plant Response to Fire
When top-killed by fire, blackgum and swamp tupelo sprout prolifically, with individuals producing several sprouts each [44]. In a study conducted in the southern Appalachians, trees 1 to 4 inches (2.5-10 cm) d.b.h. sprouted quickly following a once-over broadcast burn [32].
The following Research Project Summaries provide information on prescribed fire and postfire response of plant community species, including blackgum, that was not available when this species review was written:
- Early postfire effects of a prescribed fire in the southern Appalachians of North Carolina
- Early postfire response of southern Appalachian Table Mountain-pitch pine stands to prescribed fires in North Carolina and Virginia
- Early postfire response of Table Mountain pine stands burned under prescription at varying intensities
Fire Regimes
For fire regime information, search FEIS for this species by entering the species name or acronym on the home page and selecting “Fire Regime” as the publication type.
Fire Management Considerations
Fire can be a useful management tool for controlling blackgum and other hardwoods. Depending on the season and type of treatment, repeated burning over a long period of time has been reported as an effective control of blackgum [38,54]. Riebold [47] suggests annual winter prescribed burns for controlling blackgum and other hardwoods up to 1 to 2 inches (2.5-5 cm) d.b.h. Blackgum will sprout, but the sprouts can be killed by repeated winter fires before they reach 1 to 2 inch (2.5-5 cm) d.b.h.
Repeated summer fires in the early growing season when the leaves are fully expanded is also a very effective method of weakening and eventually killing blackgum [11].
Federal Status
None
Other Status
No entry.
Importance to Wildlife and Livestock
Blackgum fruits.
Blackgum sprouts are commonly browsed by white-tailed deer but lose palatability with age [8,16,30]. The fruit is high in nutrients and is eaten by a variety of birds and mammals [4,27,37].
Palatability and Nutritional Value
Stump sprouts of blackgum are reported to be a moderate to high palatability browse to white-tailed deer [16,30].
Percent mean nutrient values of blackgum on unburned plots in southern pine forests were as follows [36]:
| Season | Protein | Fat | Fiber | N-free extract | Ash | Phosphorus | Calcium |
|---|---|---|---|---|---|---|---|
| Summer | 7.64 | 2.33 | 32.84 | 44.01 | 2.63 | 0.06 | 1.10 |
Cover Value
Blackgum and swamp tupelo provide cavity and nesting sites for a variety of birds and mammals [3,7,29].
Value for Rehabilitation or Restoration of Disturbed Sites
No entry.
Other Uses
Because of its straight bole, shapely crown, and attractive autumn foliage, blackgum and swamp tupelo are often planted as ornamentals. Bees utilize the nectar from the flowers of black and swamp tupelo to produce honey [44,51].
Blackgum and swamp tupelo wood is used mainly for lumber, veneer, paper pulp, and to some extent for railroad ties [10,50]. The veneer is used mainly for boxes, crates, baskets, furniture, and interior woodwork. Because of its toughness, blackgum is also used for flooring, rollers in glass factories, blocks, gunstocks, and pistol grips [15,52].
Other Management Considerations
Silviculture: Seedling establishment of blackgum is best accomplished by the shelterwood method. Regeneration can also be accomplished by clearcutting if it follows a good seed fall or if advanced regeneration is already established [9,18,]. Silvicultural practices for regenerating blackgum have been described [25].
Animal damage: Due to the high palatability of seedling and sprouts, blackgum can be eliminated or greatly reduced when deer populations are high [16].
Insects and diseases: The two most important insects that attack black and swamp tupelo are the tupelo leaf miner (Antispila nyssaefoliella) and the forest tent caterpillar (Malacosoma disstria). Infestation of these insects cause growth loss and occasional mortality. Fire scars often serve as entry points for a large number of heart rot fungi [44].
Control: Blackgum and swamp tupelo may compete with loblolly and shortleaf pine (Pinus taeda and P. echinata) stands for water and light, reducing their growth and development [28].
Table A1— Forest and range ecosystems, Bureau of Land Management (BLM) physiographic regions, Kuchler plant associations, Society for American Foresters (SAF) forest cover types, and Society for Rangeland Management (SRM) rangeland cover types in which this species occurs.
Forest and Range Ecosystems (Garrison et al. 1977)
- FRES10 White - red - jack pine
- FRES11 Spruce - fir
- FRES12 Longleaf - slash pine
- FRES13 Loblolly - shortleaf pine
- FRES14 Oak - pine
- FRES15 Oak - hickory
- FRES16 Oak - gum - cypress
BLM Physiographic Regions (Bernard and Brown 1977)
- No entry.
Kuchler Plant Associations (Kuchler 1964)
- K089 Black Belt
- K090 Live oak - sea oats
- K091 Cypress savanna
- K095 Great Lakes pine forest
- K097 Southeastern spruce - fir forest
- K100 Oak - hickory forest
- K101 Elm - ash forest
- K102 Beech - maple forest
- K103 Mixed mesophytic forest
- K104 Appalachian oak forest
- K111 Oak - hickory - pine forest
- K112 Southern mixed forest
- K113 Southern floodplain forest
- K114 Pocosin
- K115 Sand pine scrub
SAF Cover Types (Eyre 1980)
- 39 Black ash - American elm - red maple
- 40 Post oak - blackjack oak
- 43 Bear oak
- 44 Chestnut oak
- 45 Pitch pine
- 46 Eastern redcedar
- 51 White pine - chestnut oak
- 52 White oak - black oak - northern red oak
- 53 White oak
- 55 Northern red oak
- 57 Yellow-poplar
- 58 Yellow-poplar - eastern hemlock
- 59 Yellow-poplar - white oak - northern red oak
- 65 Pin oak - sweetgum
- 70 Longleaf pine
- 75 Shortleaf pine
- 76 Shortleaf pine - oak
- 78 Virginia pine - oak
- 79 Virginia pine
- 80 Loblolly pine - shortleaf pine
- 81 Loblolly pine
- 82 Loblolly pine - hardwood
- 83 Longleaf pine - slash pine
- 85 Slash pine - hardwood
- 87 Sweetgum - yellow poplar
- 91 Swamp chestnut oak - cherrybark oak
- 93 Sugarberry - American elm - green ash
- 97 Atlantic white-cedar
- 100 Pond cypress
- 104 Sweetbay - swamp tupelo - redbay
- 110 Black oak
SRM Rangeland Cover Types (Shiflet 1994)
- No entry.
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