Rhus michauxii
Encyclopedia
Rhus michauxii is a rare species of flowering plant in the cashew family
known by the common names Michaux's sumac and false poison sumac. It is endemic to the southeastern United States, where it can be found in the states of Virginia
, North Carolina
, South Carolina
and Georgia
. It is threatened by the loss and degradation of its habitat and by barriers to reproduction. It is a federally listed endangered species
of the United States.
This plant is a small shrub
growing 30 to 60 centimeters tall. It is very hairy in texure. The small size and hairiness distinguish the plant from other sumac
s. The long leaves are each made up of several pairs of toothed leaflets. The plant is dioecious
with male and female reproductive parts occurring on separate plants. The female plant produces an erect inflorescence
of white or greenish yellow flowers and red drupe
s. This plant was first described as Rhus pumila by André Michaux
in 1803, and it was renamed for Michaux in 1895.
This shrub grows in wooded areas often on clay
or decomposed granite
soils. It occurs in sandhill
s habitat in loam
y soils. The habitat may be dominated by longleaf pine and oak
s and it may grow alongside Ceanothus americanus
, Paspalum bifidum, Tridens carolinianus, Aristida lanosa, Onosmodium virginianum, and Helianthus divaricatus
. Other associates and indicators of the plant include Liquidambar styraciflua, Cornus florida, Rhus glabra
, R. copallinum, Schizachyrium scoparium Sorghastrum elliottii, Brickellia eupatorioides, Eupatorium godfreyanum, E. sessilifolium
, Silphium compositum, Helianthus divaricatus
, Helianthus strumosus, Viburnum rafinesquianum, Scleria oligantha, Clematis ochroleuca, Sanicula smallii, Salvia urticifolia
, and Parthenium auriculatum. The area is generally somewhat more moist than surrounding habitat types. The plant requires openings in the vegetation so it can receive sunlight.
Half of the recorded populations of this plant have been extirpated
. Much of its habitat has been cleared for residential, industrial, and agricultural operations, including silviculture
, and the construction of roads. Remaining habitat is degraded by the lack of a normal fire regime
. The plant does not tolerate shade and it grows naturally in openings maintained by wildfire
. Today, fire suppression is practiced and normal periodic wildfires are prevented. The result is overgrowth of the vegetation, which shades out the rare shrub.
This plant also has difficulty reproducing. It is clonal
, often reproducing vegetatively
, so populations are low in genetic variability
. It may hybridize with the common Rhus glabra. This union forms Rhus × ashei, a natural hybrid. One major reproductive problem is that many populations are composed entirely of one sex. Furthermore, the populations are small and very widely spaced, making reproduction impossible. As the plant requires open habitat, it may arise in artificially cleared areas such as roadsides. There it is vulnerable to destruction from construction, maintenance, and herbicides.
Conservation activities include genetic analysis
in an effort to understand the genetic variability of populations. Plant propagation
techniques are being studied. Plants are being reintroduced to appropriate habitat, including the placement of opposite-sex plants into single-sex populations. Plants are transplanted from high-risk areas to better habitat for their survival. Prescribed burns help to create openings where the plant can thrive.
Anacardiaceae
Anacardiaceae are a family of flowering plants bearing fruits that are drupes and in some cases producing urushiol, an irritant. Anacardiaceae include numerous genera with several of economic importance. Notable plants in this family include cashew , mango, poison ivy, sumac, smoke tree, and marula...
known by the common names Michaux's sumac and false poison sumac. It is endemic to the southeastern United States, where it can be found in the states of Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...
, North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
, South Carolina
South Carolina
South Carolina is a state in the Deep South of the United States that borders Georgia to the south, North Carolina to the north, and the Atlantic Ocean to the east. Originally part of the Province of Carolina, the Province of South Carolina was one of the 13 colonies that declared independence...
and Georgia
Georgia (U.S. state)
Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...
. It is threatened by the loss and degradation of its habitat and by barriers to reproduction. It is a federally listed endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
of the United States.
This plant is a small shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
growing 30 to 60 centimeters tall. It is very hairy in texure. The small size and hairiness distinguish the plant from other sumac
Sumac
Sumac is any one of approximately 250 species of flowering plants in the genus Rhus and related genera, in the family Anacardiaceae. Sumacs grow in subtropical and temperate regions throughout the world, especially in Africa and North America....
s. The long leaves are each made up of several pairs of toothed leaflets. The plant is dioecious
Plant sexuality
Plant sexuality covers the wide variety of sexual reproduction systems found across the plant kingdom. This article describes morphological aspects of sexual reproduction of plants....
with male and female reproductive parts occurring on separate plants. The female plant produces an erect inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
of white or greenish yellow flowers and red drupe
Drupe
In botany, a drupe is a fruit in which an outer fleshy part surrounds a shell of hardened endocarp with a seed inside. These fruits develop from a single carpel, and mostly from flowers with superior ovaries...
s. This plant was first described as Rhus pumila by André Michaux
André Michaux
André Michaux was a French botanist and explorer.-Biography:Michaux was born in Satory, now part of Versailles, Yvelines. After the death of his wife within a year of their marriage he took up the study of botany and was a student of Bernard de Jussieu...
in 1803, and it was renamed for Michaux in 1895.
This shrub grows in wooded areas often on clay
Clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...
or decomposed granite
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...
soils. It occurs in sandhill
Sandhill
A sandhill is a type of ecological community or xeric wildfire-maintained ecosystem. It is not the same as a sand dune. It features very short fire return intervals, one to five years. Without fire, sandhills undergo ecological succession and become more oak dominated.Entisols are the typical...
s habitat in loam
Loam
Loam is soil composed of sand, silt, and clay in relatively even concentration . Loam soils generally contain more nutrients and humus than sandy soils, have better infiltration and drainage than silty soils, and are easier to till than clay soils...
y soils. The habitat may be dominated by longleaf pine and oak
Oak
An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...
s and it may grow alongside Ceanothus americanus
Ceanothus americanus
Ceanothus americanus is a species of shrub native to North America. Common names include New Jersey tea, Jersey tea ceanothus, variations of red root , and mountain sweet , and wild snowball...
, Paspalum bifidum, Tridens carolinianus, Aristida lanosa, Onosmodium virginianum, and Helianthus divaricatus
Helianthus divaricatus
Helianthus divaricatus, commonly known as the woodland sunflower, is a perennial herb in the composite family. It is native to eastern North America, from Ontario and Quebec in the north, south to Florida and west to Oklahoma and Iowa. It commonly occurs in dry, relatively open sites...
. Other associates and indicators of the plant include Liquidambar styraciflua, Cornus florida, Rhus glabra
Rhus glabra
Rhus glabra is a species of sumac in the family Anacardiaceae, native to North America, from southern Quebec west to southern British Columbia in Canada, and south to northern Florida and Arizona in the United States and Tamaulipas in northeastern Mexico.One of the easiest shrubs to identify...
, R. copallinum, Schizachyrium scoparium Sorghastrum elliottii, Brickellia eupatorioides, Eupatorium godfreyanum, E. sessilifolium
Eupatorium sessilifolium
Eupatorium sessilifolium, commonly called Upland Boneset or Sessile-leaved Boneset, is a herbaceous perennial plant in the family Asteraceae. This species is native to eastern North America, where it blooms in late summer with white flowers....
, Silphium compositum, Helianthus divaricatus
Helianthus divaricatus
Helianthus divaricatus, commonly known as the woodland sunflower, is a perennial herb in the composite family. It is native to eastern North America, from Ontario and Quebec in the north, south to Florida and west to Oklahoma and Iowa. It commonly occurs in dry, relatively open sites...
, Helianthus strumosus, Viburnum rafinesquianum, Scleria oligantha, Clematis ochroleuca, Sanicula smallii, Salvia urticifolia
Salvia urticifolia
Salvia urticifolia is a herbaceous perennial native to the southeastern United States. S. urticifolia is an erect plant that reaches tall. Flowers, with a corolla that is approximately long, are blue or purple , growing in panicles on short pedicels...
, and Parthenium auriculatum. The area is generally somewhat more moist than surrounding habitat types. The plant requires openings in the vegetation so it can receive sunlight.
Half of the recorded populations of this plant have been extirpated
Local extinction
Local extinction, also known as extirpation, is the condition of a species which ceases to exist in the chosen geographic area of study, though it still exists elsewhere...
. Much of its habitat has been cleared for residential, industrial, and agricultural operations, including silviculture
Silviculture
Silviculture is the practice of controlling the establishment, growth, composition, health, and quality of forests to meet diverse needs and values. The name comes from the Latin silvi- + culture...
, and the construction of roads. Remaining habitat is degraded by the lack of a normal fire regime
Fire regime
A fire regime is the pattern, frequency and intensity of the bushfires and wildfires that prevails in an area. It is an integral part of fire ecology, and renewal for certain types of ecosystems. If fires are too frequent, plants may be killed before they have matured, or before they have set...
. The plant does not tolerate shade and it grows naturally in openings maintained by wildfire
Wildfire
A wildfire is any uncontrolled fire in combustible vegetation that occurs in the countryside or a wilderness area. Other names such as brush fire, bushfire, forest fire, desert fire, grass fire, hill fire, squirrel fire, vegetation fire, veldfire, and wilkjjofire may be used to describe the same...
. Today, fire suppression is practiced and normal periodic wildfires are prevented. The result is overgrowth of the vegetation, which shades out the rare shrub.
This plant also has difficulty reproducing. It is clonal
Cloning
Cloning in biology is the process of producing similar populations of genetically identical individuals that occurs in nature when organisms such as bacteria, insects or plants reproduce asexually. Cloning in biotechnology refers to processes used to create copies of DNA fragments , cells , or...
, often reproducing vegetatively
Vegetative 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...
, so populations are low in genetic variability
Genetic variability
Genetic variability is a measure of the tendency of individual genotypes in a population to vary from one another. Variability is different from genetic diversity, which is the amount of variation seen in a particular population. The variability of a trait describes how much that trait tends to...
. It may hybridize with the common Rhus glabra. This union forms Rhus × ashei, a natural hybrid. One major reproductive problem is that many populations are composed entirely of one sex. Furthermore, the populations are small and very widely spaced, making reproduction impossible. As the plant requires open habitat, it may arise in artificially cleared areas such as roadsides. There it is vulnerable to destruction from construction, maintenance, and herbicides.
Conservation activities include genetic analysis
Genetic analysis
Genetic analysis can be used generally to describe methods both used in and resulting from the sciences of genetics and molecular biology, or to applications resulting from this research....
in an effort to understand the genetic variability of populations. Plant propagation
Plant propagation
Plant propagation is the process of creating new plants from a variety of sources: seeds, cuttings, bulbs and other plant parts. Plant propagation can also refer to the artificial or natural dispersal of plants.-Sexual propagation :...
techniques are being studied. Plants are being reintroduced to appropriate habitat, including the placement of opposite-sex plants into single-sex populations. Plants are transplanted from high-risk areas to better habitat for their survival. Prescribed burns help to create openings where the plant can thrive.