Pondberry | |
---|---|
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Magnoliids |
Order: | Laurales |
Family: | Lauraceae |
Genus: | Lindera |
Species: | L. melissifolia |
Binomial name | |
Lindera melissifolia | |
Natural range in North America | |
Synonyms [4] [5] [6] | |
Lindera melissifolia, common name pondberry or southern spicebush, is a stoloniferous, 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 wetlands for agriculture and forestry. [7] [8] Restoration efforts are currently being conducted.
Form: Pondberry occurs in dense thickets with erect or ascending shoots up to 2 m (6.6 ft) tall and few branches; stems are connected underground by stolons. Thickets of female plants tend to be smaller than those of males and are sometimes absent from populations. [9] Die-back of stems is a fairly common occurrence.
Foliage: The drooping, alternate leaves are oblong-elliptic to narrowly ovate, 5–16 cm (2.0–6.3 in) long, 2–6 cm (0.8–2.4 in) wide, and tend to be strongly tapered to a point at the tip. [10] Undersides are strongly net-veined and covered with short, soft hairs. When crushed, the leaves strongly resemble sassafras ( Sassafras albidum ) in fragrance. [8] Foliage is deciduous.
Flowers: Stems flower after two to four years of growth. [11] Male and female flowers, each 5–6 mm (0.20–0.24 in) across, are produced on different plants (dioecious). [9] 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 (0.08 in) 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. [7] Flowers are thought to be insect pollinated. [11] Late season frosts occasionally damage flowers, resulting in reduced fruit set.
Fruit: A bright red, single-seeded drupe, ellipsoid, 10–12 mm (0.4–0.5 in) long matures in late summer or fall (August to early October). Individual fruit stalks are 9–12 mm (0.4–0.5 in) long, 2.5–3 mm (0.10–0.12 in) 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. [7]
Pondberry occurs in shallow depression ponds in wetland habitats with hydric soils, 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. [12] 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 has probably always been a rare species, and knowledge of its ecology is limited. [11] In Mississippi, pondberry occurs in bottomland hardwood forests. In northeastern Arkansas and southeastern Missouri 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. [11]
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. [10]
Clones expand vegetatively through stolons, and this mechanism of vegetative reproduction 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. [8] Thus, mature colonies often include some dead stems intermingled with numerous live stems.
Despite the regular production of mature fruit, virtually no seedlings of pondberry have been observed at any of the known sites. [11] 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. [13]
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 ). [13] 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 ). [13] 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. [14] [15] 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. [16]
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. [16] [17] 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.
Pondberry fruit are eaten by hermit thrushes, northern cardinals, and perhaps other birds. [13] 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 ). [18] 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 spp.) cut circular sections from the leaf margins, sometimes removing most of the leaf. [16]
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. [19] [20]
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). [21] 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.
Pondberry was listed as endangered in 1986. [2] [3] 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. [7]
A critical part of the restoration effort is to increase the knowledge about pondberry's ecology and reproduction. [12] 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.
Lauraceae, or the laurels, is a plant family that includes the true laurel and its closest relatives. This family comprises about 2850 known species in about 45 genera worldwide. They are dicotyledons, and occur mainly in warm temperate and tropical regions, especially Southeast Asia and South America. Many are aromatic evergreen trees or shrubs, but some, such as Sassafras, are deciduous, or include both deciduous and evergreen trees and shrubs, especially in tropical and temperate climates. The genus Cassytha is unique in the Lauraceae in that its members are parasitic vines. Most laurels are highly poisonous.
Trillium grandiflorum, the white trillium, large-flowered trillium, great white trillium, white wake-robin or French: trille blanc, is a species of flowering plant in the family Melanthiaceae. A monocotyledonous, herbaceous perennial, the plant is native to eastern North America, from northern Quebec to the southern parts of the United States through the Appalachian Mountains into northernmost Georgia and west to Minnesota. There are also several isolated populations in Nova Scotia, Maine, southern Illinois, and Iowa.
Annona glabra is a tropical fruit tree in the family Annonaceae, in the same genus as the soursop and cherimoya. Common names include pond apple, alligator apple, swamp apple, corkwood, bobwood, and monkey apple. The tree is native to Florida in the United States, the Caribbean, Central and South America, and West Africa. It is common in the Everglades. The A. glabra tree is considered an invasive species in Sri Lanka and Australia. It grows in swamps, is tolerant of saltwater, and cannot grow in dry soil.
Lindera benzoin is a shrub in the laurel family. It is native to eastern North America, ranging from Maine and New York to Ontario in the north, and to Kansas, Texas, and northern Florida in the center and south. Within its native range it is a relatively common plant where it grows in the understory in moist, rich woods, especially those with exposed limestone.
Lindera is a genus of about 80–100 species of flowering plants in the family Lauraceae, mostly native to eastern Asia but with three species in eastern North America. The species are shrubs and small trees; common names include spicewood, spicebush, and Benjamin bush.
Platanthera yadonii, also known as Yadon's piperia or Yadon's rein orchid, is an endangered orchid endemic to a narrow range of coastal habitat in northern Monterey County, California. In 1998 this plant was designated as an endangered species by the United States government, the major threat to its survival being continuing land development from an expanding human population and associated habitat loss. One of the habitats of Yadon's piperia, the Del Monte Forest near Monterey, California, is the subject of a federal lawsuit, based upon endangerment of this organism along with several other endangered species.
Schwalbea americana, commonly known as American chaffseed, is the sole species currently classified in the genus Schwalbea. It is an erect, hemiparasitic, perennial herb in the family Orobanchaceae. It is native to the southeastern United States where it is found in wet acidic grasslands. This species has declined tremendously from its historical range due to fire suppression, and it is currently listed as "Endangered" by the U.S. Fish and Wildlife Service.
The Mauna Loa silversword, Argyroxiphium kauense, or Kaʻū silversword, is a rare species of flowering plant in the aster family. It is endemic to the eastern and southern slopes of Mauna Loa on the island of Hawaiʻi. A. kauense occurs in mountainous shrublands, bogs, and open mesic forest. The species is managed by the National Park Service and Hawaiʻi State Department of Forestry and Wildlife. It is a federally listed endangered species of the United States. There are three known populations remaining, for a total of fewer than 1000 individuals.
Bidens amplectens, the Waiʻanae kokoʻolau, is a species of flowering plant in the family Asteraceae. It belongs to the genus Bidens, collectively called kokoʻolau or koʻokoʻolau in the Hawaiian language. It is found in coastal and dry lowland habitats in the Waiʻanae Range on Oʻahu. It is threatened by habitat loss due to the spread of invasive weeds and brush fires. The species is also threatened by climate change and habitat degradation, and herbivory. Bidens amplectens is currently listed as endangered under the Endangered Species Act.
Asimina tetramera, commonly known as the four-petal pawpaw, is a rare species of small tree or perennial shrub endemic to Martin and Palm Beach Counties in the state of Florida. The species is currently listed as endangered under the Endangered Species Act and as endangered by the International Union for Conservation. The four-petal pawpaw is part of the Annonaceae family alongside other Asimina species.
Callicarpa ampla, also called the capa rose, is a species of plant in the family Lamiaceae. It is found in Puerto Rico in the Caribbean region. It is threatened by habitat loss and is a critically endangered plant species.
Laurel wilt, also called laurel wilt disease, is a vascular disease that is caused by the fungus Raffaelea lauricola, which is transmitted by the invasive redbay ambrosia beetle, Xyleborus glabratus. The disease affects and kills members of the laurel family. The avocado is perhaps the most commercially valuable plant affected by laurel wilt.
Warea carteri is a species of plant in the mustard family, Brassicaceae, known by the common names Carter's pinelandcress and Carter's mustard. It is an endangered, fire-dependent annual herb occurring in xeric, shrub-dominated habitats on the Lake Wales Ridge of central Florida in the United States.
Cirsium vinaceum is a rare species of thistle known by the common name Sacramento Mountains thistle. It is endemic to Otero County, New Mexico, in the United States, where it is known only from the Sacramento Mountains. The plant can be found in six canyon systems in a southern section of this mountain range spanning about 32 kilometers. It is rare because it is limited to a specific type of mountain wetland which is both naturally uncommon and threatened by a number of forces. The plant was federally listed as threatened in 1987.
Conradina verticillata is a flowering shrub in the mint family, found in the Cumberland Plateau. It is also called Conradina montana, Cumberland rosemary or Cumberland false rosemary. It has been classified as a threatened species under the Endangered Species Act since 1991.
Phacelia argillacea is a rare species of flowering plant in the borage family known by the common names clay phacelia and Atwood's phacelia. It is endemic to Utah in the United States, where it is known only from one canyon in Utah County. It is "one of Utah's most endangered species"; it is "one of the nation's rarest plants" and is federally listed as an endangered species of the United States.
Polygala lewtonii is a rare species of flowering plant in the milkwort family known by the common name Lewton's polygala, or Lewton's milkwort. It is endemic to Florida in the United States, where it is limited to the central ridge of the peninsula. There are about 49 occurrences of the plant remaining. Most occurrences contain very few plants. The species is threatened by the loss and degradation of its habitat. This is a federally listed endangered species of the United States.
Carex lacustris, known as lake sedge, is a tufted grass-like perennial of the sedge family (Cyperaceae), native to southern Canada and the northern United States. C. lacustris us an herbaceous surface-piercing plant that grows in water up to 50 cm (1.6 ft) deep, and grows 50–150 cm (1.6–4.9 ft) tall. It grows well in marshes and swampy woods of the boreal forest, along river and lake shores, in ditches, marshes, swamps, and other wetland habitat. It grows on muck, sedge peat, wet sand or silt, in filtered or full sunlight.
Croton alabamensis var. texensis is a variety of Croton alabamensis that is endemic to the state of Texas in the United States. It is commonly known as the Texabama croton.
Arctostaphylos glandulosa subsp. crassifolia is a rare perennial shrub, a subspecies of manzanita within the heather family commonly known as the Del Mar manzanita. It is narrowly endemic to the sandstone coastal terraces of San Diego County and northwestern Baja California. It is a burl-forming evergreen shrub typically found growing in a rambling habit on poor soils and hardpan. From December to February, white to pink urn-shaped flowers decorate its foliage, giving way to small fruits. It is listed as endangered and is threatened by land development, invasive species and modifications to the natural fire regime.