Lindera melissifolia
Encyclopedia
Lindera melissifolia, common name Pondberry or Southern Spicebush, is a stolon
iferous, deciduous
, aromatic shrub in the laurel family
. This endangered species is native to the southeastern United States, and its demise is associated with habitat loss from extensive drainage of wetland
s for agriculture and forestry. Restoration efforts are currently being conducted.
Foliage: The drooping, alternate leaves are oblong-elliptic to narrowly ovate, 5-16 cm long, 2-6 cm wide, and tend to be strongly tapered to a point at the tip. Undersides are strongly net-veined and covered with short, soft hairs. When crushed, leaves, strongly resemble sassafras (Sassafras albidum
) in fragrance. Foliage is deciduous.
Flowers: Stems flower after 2 to 4 years of growth.Devall, Margaret; Schiff, Nathan; Boyette, Douglas. 2001. Ecology and reproductive biology of the endangered pondberry, Lindera melissifolia (Walt) Blume. Natural Areas Journal. 21:250-258. Male and female flowers, each 5-6 mm across, are produced on different plants (dioecious
). Flowers appear before the leaves (February to mid-March) in tight, stalkless clusters. The petal-like tepals are pale to bright yellow, oblong, and 2 mm long. Male flowers occur in dense clusters, with 9-12 stamens surrounded by two whorls of tepals. Female flowers are less conspicuous, with fewer flowers per cluster and a single pistil surrounded by two whorls of tepals; the outer whorl is petal-like and the inner whorl is reduced to nectar-producing scales. Flowers remain open for about 1 week making thickets conspicuous. Flowers are thought to be insect pollinated. Late season frosts occasionally damage flowers, resulting in reduced fruit set.
Fruit: A bright red, single-seeded drupe, ellipsoid, 10-12 mm long matures in late summer or fall (August to early October). Individual fruit stalks are 9-12 mm long, 2.5-3.0 mm thick, and appear swollen at the apex. Stalks persist beyond fruit fall; their presence indicates the plant's sex and past level of fruit production. Fruit production is highly variable from year-to-year, ranging from 0 to 150 fruit per stem.
s, along margins of cypress ponds, and in seasonally wet, low areas among bottomland hardwoods. At present there are some 36 populations in Alabama, Arkansas, Georgia, Mississippi, Missouri, North Carolina, and South Carolina. It has apparently been extirpated from Louisiana and possibly Florida. Most of these populations are located in Lower Mississippi Alluvial Plain
, with the largest population being in the Delta National Forest
in western Mississippi.
pondberry is found on the bottoms and edges of shallow seasonal ponds in old dune fields, but in southeastern Arkansas it occurs in low habitat along a river. In South Carolina the species occurs in areas with karst
topography, around the edges of sinkholes, and in Georgia it occurs along the borders of sphagnum bogs. Sunlight at the different sites ranges from deep shade to almost full sun. Most pondberry colonies occur in light shade beneath a forest canopy, but a few grow in almost full sunlight. Pondberry appears to be able to occupy widely different habitats as long as its requirements for water are met. In open conditions, competition from other plant species may be a problem.
Many of the remaining populations consist only of male plants and are apparently the sprouts of a single individual. Habitat fragmentation severely affects dioecious species like pondberry because populations with plants of a single sex can only vegetatively reproduce. With significant habitat loss, plants become ever more isolated, lessening the likelihood that pollinators will travel from male to female plants.
is the principal way that colonies develop. Stems usually live 6 or 7 years, and when a stem dies it is usually replaced by a new stem that grows from the base of the plant. Thus, mature colonies often include some dead stems intermingled with numerous live stems.
Despite the regular production of mature fruit, virtually no seedling
s of pondberry have been observed at any of the known sites. The cause of this apparent lack of natural reproduction is not currently known, but the consequences are clear—it severely reduces the species' chance for long-term survival. Sexual reproduction of pondberry is critical for long-range dispersal and genetic diversity.
Before modern flood control was imposed along the Mississippi River and its tributaries, historic floods may have been an important mechanism in fruit and/or seed dispersal
over long distances or for creating suitable conditions for seedling establishment. Although the fruit of pondberry sinks in water after a short time, the seed with the pulp removed will float for a day or sometimes longer.
Characteristics of pondberry's fruit—the showy color, fleshy pulp, and its persistent on stems—suggest that animals, particularly birds, may be important dispersal agents. Of 82 bird species observed in the vicinity of pondberry thickets in fruit, only two species were observed to eat the fruit—hermit thrushes (Catharus guttatus) and northern cardinals (Cardinalis cardinalis). Of these, the cardinals destroyed the seed by crushing and is thus considered a seed predator. However, the hermit thrush swallows the whole fruit and later regurgitates the seed, indicating that it is an important seed disperser. The foraging habits of the thrush suggests that most of the seeds would be dispersed with 100 m of existing female colonies. Mammals may also be potential dispersers of pondberry seeds, including the raccoon (Procyon lotor) and opossum (Didelphis virginiana). Historically, the black bear (Ursus americanus) may have been important to seed dispersal.
Seed germination does not appear to be a deterrent to seedling establishment. Fairly high rates of germination have been reported under both controlled and field conditions. Removal of the fruit's pulp and sowing seeds into the soil favor germination. Under field conditions, germination of sown seeds has been observed to occur over a number of years suggesting some form of dormancy
.
The artificial establishment of pondberry to new areas may be needed if the species is to recover. Plants have been successfully transplanted from existing colonies to suitable locations. The transplants seem to do well in some locations although survivorship and growth has been low in others. Both transplants and seedlings do well under cultivation in a nursery setting, which has been used to provide planting stock for creating new colonies in field locations.
The spicebush swallowtail (Papilio troilus) larvae feed on the leaves and roll themselves in a leaf making a tent. Leaf cutter bees (Megachilidae
spp.) cut circular sections from the leaf margins, sometimes removing most of the leaf.
A vintage use of pondberry fruit in the rural South was as projectiles in toy pop guns constructed by children from hollowed-out elderberry (Sambucus canadensis
) stems.
There are indications that pondberry, which is in the Laurel family, is susceptible to laurel wilt (Raffaelea lauricola). This fungal disease is introduced into host plants by a non-native insect, the redbay ambrosia beetle (Xyleborus glabratus) and kills the plant by plugging the water-conducting cells of the afflicted individual, causing it to wilt and eventually die. There is no known cure for this disease, which has quickly spread through other members of the laurel family (especially redbay, Persia borbonia) from the coast of South Carolina inland towards the native habitat of pondberry.
A critical part of the restoration effort is to increase the knowledge about pondberry's ecology and reproduction. A team of researchers from the U.S. Forest Service's Southern Research Station are working with the U.S. Army Corps of Engineers and the U.S. Fish and Wildlife Service to learn as much as they can about the biology and ecology of pondberry. Scientists are investigating the role of flooding and light availability on pondberry at a large-scale impoundment facility, and they have set up controlled experiments to study competition, seed germination, seed storage, and seed persistence in the soil seed bank
. An integrated approach is being used to learn more about pondberry's ecology, insect predators, fungal pathogens, physiological responses to light availability and flooding, population genetics, seed physiology, and seed dispersal.
Stolon
In biology, stolons are horizontal connections between organisms. They may be part of the organism, or of its skeleton; typically, animal stolons are external skeletons.-In botany:...
iferous, deciduous
Deciduous
Deciduous means "falling off at maturity" or "tending to fall off", and is typically used in reference to trees or shrubs that lose their leaves seasonally, and to the shedding of other plant structures such as petals after flowering or fruit when ripe...
, aromatic shrub in the laurel family
Lauraceae
The Lauraceae or Laurel family comprises a group of flowering plants included in the order Laurales. The family contains about 55 genera and over 3500, perhaps as many as 4000, species world-wide, mostly from warm or tropical regions, especially Southeast Asia and South America...
. This endangered species is native to the southeastern United States, and its demise is associated with habitat loss from extensive drainage of wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....
s for agriculture and forestry. Restoration efforts are currently being conducted.
Description
Form: Pondberry occurs in dense thickets with erect or ascending shoots up to 2 m tall and few branches; stems are connected underground by stolons. Thickets of female plants tend to be shorter lived and smaller than those of males and are sometimes absent from populations. Die-back of stems is a fairly common occurrence.Foliage: The drooping, alternate leaves are oblong-elliptic to narrowly ovate, 5-16 cm long, 2-6 cm wide, and tend to be strongly tapered to a point at the tip. Undersides are strongly net-veined and covered with short, soft hairs. When crushed, leaves, strongly resemble sassafras (Sassafras albidum
Sassafras albidum
Sassafras albidum is a species of Sassafras native to eastern North America, from southern Maine and southern Ontario west to Iowa, and south to central Florida and eastern Texas. It occurs throughout the eastern deciduous forest habitat type, at altitudes of sea level up to 1,500 m...
) in fragrance. Foliage is deciduous.
Flowers: Stems flower after 2 to 4 years of growth.Devall, Margaret; Schiff, Nathan; Boyette, Douglas. 2001. Ecology and reproductive biology of the endangered pondberry, Lindera melissifolia (Walt) Blume. Natural Areas Journal. 21:250-258. Male and female flowers, each 5-6 mm across, are produced on different plants (dioecious
Dioecious
Dioecy is the property of a group of biological organisms that have males and females, but not members that have organs of both sexes at the same time. I.e., those whose individual members can usually produce only one type of gamete; each individual organism is thus distinctly female or male...
). Flowers appear before the leaves (February to mid-March) in tight, stalkless clusters. The petal-like tepals are pale to bright yellow, oblong, and 2 mm long. Male flowers occur in dense clusters, with 9-12 stamens surrounded by two whorls of tepals. Female flowers are less conspicuous, with fewer flowers per cluster and a single pistil surrounded by two whorls of tepals; the outer whorl is petal-like and the inner whorl is reduced to nectar-producing scales. Flowers remain open for about 1 week making thickets conspicuous. Flowers are thought to be insect pollinated. Late season frosts occasionally damage flowers, resulting in reduced fruit set.
Fruit: A bright red, single-seeded drupe, ellipsoid, 10-12 mm long matures in late summer or fall (August to early October). Individual fruit stalks are 9-12 mm long, 2.5-3.0 mm thick, and appear swollen at the apex. Stalks persist beyond fruit fall; their presence indicates the plant's sex and past level of fruit production. Fruit production is highly variable from year-to-year, ranging from 0 to 150 fruit per stem.
Habitat/Range
Pondberry occurs in shallow depression ponds in wetland habitats with hydric soilHydric soil
A hydric soil is a soil that formed under conditions of saturation, flooding, or ponding long enough during the growing season to develop anaerobic conditions in the upper part....
s, along margins of cypress ponds, and in seasonally wet, low areas among bottomland hardwoods. At present there are some 36 populations in Alabama, Arkansas, Georgia, Mississippi, Missouri, North Carolina, and South Carolina. It has apparently been extirpated from Louisiana and possibly Florida. Most of these populations are located in Lower Mississippi Alluvial Plain
Mississippi Alluvial Plain
The Mississippi River Alluvial Plain is an alluvial plain created by the Mississippi River on which lies parts of seven states, from southern Louisiana to southern Illinois....
, with the largest population being in the Delta National Forest
Delta National Forest
Delta National Forest is a U.S. National Forest in western Mississippi. It is located in Sharkey County and has an area of . The forest is headquartered in Jackson, as are all six National Forests in Mississippi, but there are local ranger district offices located in Rolling Fork...
in western Mississippi.
Ecology
Pondberry has probably always been a rare species, and knowledge of its ecology is limited. In Mississippi, pondberry occurs in bottomland hardwood forests. In northeastern Arkansas and southeastern Missouripondberry is found on the bottoms and edges of shallow seasonal ponds in old dune fields, but in southeastern Arkansas it occurs in low habitat along a river. In South Carolina the species occurs in areas with karst
KARST
Kilometer-square Area Radio Synthesis Telescope is a Chinese telescope project to which FAST is a forerunner. KARST is a set of large spherical reflectors on karst landforms, which are bowlshaped limestone sinkholes named after the Kras region in Slovenia and Northern Italy. It will consist of...
topography, around the edges of sinkholes, and in Georgia it occurs along the borders of sphagnum bogs. Sunlight at the different sites ranges from deep shade to almost full sun. Most pondberry colonies occur in light shade beneath a forest canopy, but a few grow in almost full sunlight. Pondberry appears to be able to occupy widely different habitats as long as its requirements for water are met. In open conditions, competition from other plant species may be a problem.
Many of the remaining populations consist only of male plants and are apparently the sprouts of a single individual. Habitat fragmentation severely affects dioecious species like pondberry because populations with plants of a single sex can only vegetatively reproduce. With significant habitat loss, plants become ever more isolated, lessening the likelihood that pollinators will travel from male to female plants.
Propagation
Clones expand vegetatively through stolons, and this mechanism of vegetative reproductionVegetative reproduction
Vegetative reproduction is a form of asexual reproduction in plants. It is a process by which new individuals arise without production of seeds or spores...
is the principal way that colonies develop. Stems usually live 6 or 7 years, and when a stem dies it is usually replaced by a new stem that grows from the base of the plant. Thus, mature colonies often include some dead stems intermingled with numerous live stems.
Despite the regular production of mature fruit, virtually no seedling
Seedling
thumb|Monocot and dicot seedlingsA seedling is a young plant sporophyte developing out of a plant embryo from a seed. Seedling development starts with germination of the seed. A typical young seedling consists of three main parts: the radicle , the hypocotyl , and the cotyledons...
s of pondberry have been observed at any of the known sites. The cause of this apparent lack of natural reproduction is not currently known, but the consequences are clear—it severely reduces the species' chance for long-term survival. Sexual reproduction of pondberry is critical for long-range dispersal and genetic diversity.
Before modern flood control was imposed along the Mississippi River and its tributaries, historic floods may have been an important mechanism in fruit and/or seed dispersal
Seed dispersal
Seed dispersal is the movement or transport of seeds away from the parent plant. Plants have limited mobility and consequently rely upon a variety of dispersal vectors to transport their propagules, including both abiotic and biotic vectors. Seeds can be dispersed away from the parent plant...
over long distances or for creating suitable conditions for seedling establishment. Although the fruit of pondberry sinks in water after a short time, the seed with the pulp removed will float for a day or sometimes longer.
Characteristics of pondberry's fruit—the showy color, fleshy pulp, and its persistent on stems—suggest that animals, particularly birds, may be important dispersal agents. Of 82 bird species observed in the vicinity of pondberry thickets in fruit, only two species were observed to eat the fruit—hermit thrushes (Catharus guttatus) and northern cardinals (Cardinalis cardinalis). Of these, the cardinals destroyed the seed by crushing and is thus considered a seed predator. However, the hermit thrush swallows the whole fruit and later regurgitates the seed, indicating that it is an important seed disperser. The foraging habits of the thrush suggests that most of the seeds would be dispersed with 100 m of existing female colonies. Mammals may also be potential dispersers of pondberry seeds, including the raccoon (Procyon lotor) and opossum (Didelphis virginiana). Historically, the black bear (Ursus americanus) may have been important to seed dispersal.
Seed germination does not appear to be a deterrent to seedling establishment. Fairly high rates of germination have been reported under both controlled and field conditions. Removal of the fruit's pulp and sowing seeds into the soil favor germination. Under field conditions, germination of sown seeds has been observed to occur over a number of years suggesting some form of dormancy
Seed dormancy
Seed dormancy is a condition of plant seeds that prevents germination when the seeds are under optimal environmental conditions for germination. Living, non dormant seeds germinate when soil temperatures and moisture conditions are suited for cellular processes and division; dormant seeds do...
.
The artificial establishment of pondberry to new areas may be needed if the species is to recover. Plants have been successfully transplanted from existing colonies to suitable locations. The transplants seem to do well in some locations although survivorship and growth has been low in others. Both transplants and seedlings do well under cultivation in a nursery setting, which has been used to provide planting stock for creating new colonies in field locations.
Uses
Pondberry fruit are eaten by hermit thrushes, northern cardinals, and perhaps other birds. Animals observed to consume pondberry seeds located on a cleared soil surface in a hardwood forest included: northern cardinal, brown thrasher (Toxostoma rufum), swamp rabbit (Sylvilagus aquaticus), armadillo (Dasypus novemcinctus), and gray squirrel (Sciurus carolinensis). Swamp rabbits have been observed browsing on stems.The spicebush swallowtail (Papilio troilus) larvae feed on the leaves and roll themselves in a leaf making a tent. Leaf cutter bees (Megachilidae
Megachilidae
The Megachilidae are a cosmopolitan family of solitary bees whose pollen-carrying structure is restricted to the ventral surface of the abdomen...
spp.) cut circular sections from the leaf margins, sometimes removing most of the leaf.
A vintage use of pondberry fruit in the rural South was as projectiles in toy pop guns constructed by children from hollowed-out elderberry (Sambucus canadensis
Sambucus canadensis
Sambucus canadensis is a species of elderberry native to a large area of North America east of the Rocky Mountains, and south through eastern Mexico and Central America to Panama. It grows in a variety of conditions including both wet and dry soils, primarily in sunny locations.-Growth:It is a...
) stems.
Threats
A large part of pondberry habitat disappeared when forests were cut for timber or for conversion to agricultural fields, and as wetlands were drained. In some cases, wetlands were permanently flooded to construct lakes. Many of the existing colonies of pondberry are small, and occupy only a portion of the apparently suitable habitat.There are indications that pondberry, which is in the Laurel family, is susceptible to laurel wilt (Raffaelea lauricola). This fungal disease is introduced into host plants by a non-native insect, the redbay ambrosia beetle (Xyleborus glabratus) and kills the plant by plugging the water-conducting cells of the afflicted individual, causing it to wilt and eventually die. There is no known cure for this disease, which has quickly spread through other members of the laurel family (especially redbay, Persia borbonia) from the coast of South Carolina inland towards the native habitat of pondberry.
Restoration
Pondberry was listed as endangered in 1986. The U.S. Fish and Wildlife Service's restoration plan states: existing pondberry populations should be protected from forestry and agricultural management actions and protected from grazing and browsing animals; searches for new populations should be continued; areas where pondberry has not been located but provide suitable habitat should be protected; and, new populations should be established or reestablish extirpated populations at suitable sites.A critical part of the restoration effort is to increase the knowledge about pondberry's ecology and reproduction. A team of researchers from the U.S. Forest Service's Southern Research Station are working with the U.S. Army Corps of Engineers and the U.S. Fish and Wildlife Service to learn as much as they can about the biology and ecology of pondberry. Scientists are investigating the role of flooding and light availability on pondberry at a large-scale impoundment facility, and they have set up controlled experiments to study competition, seed germination, seed storage, and seed persistence in the soil seed bank
Soil Seed Bank
The soil seed bank refers to the natural storage of seeds, often dormant, within the soil of most ecosystems. The study of soil seed banks started in 1859 when Charles Darwin observed the emergence of seedlings using soil samples from the bottom of a lake. The first scientific paper on the subject...
. An integrated approach is being used to learn more about pondberry's ecology, insect predators, fungal pathogens, physiological responses to light availability and flooding, population genetics, seed physiology, and seed dispersal.
External links
- Lower Mississippi River Conservation Committee: Pondberry.
- Fish and Wildlife Service: Pondberry in North Carolina.
- North Carolina Natural Heritage Program: Pondberry.
- USGS: Southern Wetland Flora: Field Office Guide to Plant Species: Southern Spicebush.
- USDA Natural Resources Conservation Service: Plant Profile. Southern Spicebush.
- South Carolina Department of Natural Resources: Pondberry.
- Glitzenstein, Jeff. Native Plant Society and Forest Service re-invigorate endangered pondberry at Honey Hill. Journal of the South Carolina Native Plant Society. Fall 2007.