''Persea palustris'', also known as swamp bay or swampbay, is a small tree or shrub found throughout the
Southeastern United States
The Southeastern United States, also referred to as the American Southeast or simply the Southeast, is a geographical region of the United States. It is located broadly on the eastern portion of the southern United States and the southern por ...
and the
Bahamas
The Bahamas (), officially the Commonwealth of The Bahamas, is an island country within the Lucayan Archipelago of the West Indies in the Atlantic Ocean, North Atlantic. It takes up 97% of the Lucayan Archipelago's land area and is home to ...
, with much of its range overlapping with that of its relative ''
Persea borbonia''. It is generally not more than tall, with bark separated into scales by fissures across its surface. Mature leaves are green, paler on their undersides, which have prominent brownish or reddish-brown hairs. The species prefers swamps and costal areas, particularly locations with moist,
peat
Peat (), also known as turf (), is an accumulation of partially decayed vegetation or organic matter. It is unique to natural areas called peatlands, bogs, mires, moors, or muskegs. The peatland ecosystem covers and is the most efficien ...
-rich soil. It is sensitive to the
fungal disease known as
laurel wilt
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 membe ...
, even more so than related species.
Description

''Persea palustris'' can appear as a slender tree, with a trunk between tall. The trunk is usually under in diameter. More commonly, however, it grows as a shrub with stems between . The dull brown bark is typically no more than thick, with fissures separating its surface into individual scales. The branches are stout, and when young, they are
terete (have circular cross-sections) and slightly angled. During the tree's first two seasons, it is covered with a layer of rust-colored
tomentum
Tomentum may refer to:
* Plant trichomes, a covering of closely matted or fine hairs on plant leaves.
* Tomentum (anatomy)
Tomentum may refer to:
* Plant trichomes, a covering of closely matted or fine hairs on plant leaves.
* Tomentum (ana ...
, which is significantly reduced after that time and completely gone in two or three years.
The leaves can be lanceolate or long-elliptic, medium to dark green on their uppersides, with paler undersides, which are covered in distinctive brownish hairs. They are long. The flowers are small and
bisexual
Bisexuality is a romantic or sexual attraction or behavior toward both males and females, or to more than one gender. It may also be defined to include romantic or sexual attraction to people regardless of their sex or gender identity, whi ...
(having both male and female components), with 6
tepals
A tepal is one of the outer parts of a flower (collectively the perianth). The term is used when these parts cannot easily be classified as either sepals or petals. This may be because the parts of the perianth are undifferentiated (i.e. of very ...
(outer parts), 9
stamens (
pollen
Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...
-producing organs), and one
pistil
Gynoecium (; ) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) ''pistils'' ...
(which contains female reproductive parts).
They are yellow-green, with 2–3 petals, and appear in May and June.
The fruit is a small
drupe
In botany, a drupe (or stone fruit) is an indehiscent fruit in which an outer fleshy part (exocarp, or skin, and mesocarp, or flesh) surrounds a single shell (the ''pit'', ''stone'', or '' pyrena'') of hardened endocarp with a seed (''kernel'') ...
(a single seed surrounded by flesh), oblong or rounded, and about long.
The dense, reddish brown hairy coating on the leaves and branches readily distinguishes it from its relatives ''
Persea humilis
''Persea'' is a genus of about 150 species of evergreen trees belonging to the laurel family, Lauraceae. The best-known member of the genus is the avocado, ''P. americana'', widely cultivated in subtropical regions for its large, edible fruit.
...
'' and ''
Persea borbonia''.
Taxonomy
''Persea palustris'' was initially described as ''Laurus carolinensis'' by
François André Michaux
François André Michaux (16 August 1770 – 23 October 1855) was a French botanist, son of André Michaux and the namesake of Michaux State Forest in Pennsylvania. Michaux ''père'' botanized in North America for nearly a dozen years (178 ...
in 1813, and then reassigned to ''Laurus carolinensis'' var. ''pubescens'' by
Frederick Traugott Pursh.
Constantine Samuel Rafinesque
Constantine Samuel Rafinesque-Schmaltz (; October 22, 1783September 18, 1840) was a French 19th-century polymath born near Constantinople in the Ottoman Empire and self-educated in France. He traveled as a young man in the United States, ultimat ...
later described it as ''Tamala palustris'' in 1838.
Charles Sprague Sargent later used the name ''Persea pubescens'' in 1895.
In 1919, he revised its name to ''Persea palustris'', due to the naming rules adopted by the
International Botanical Congress
International Botanical Congress (IBC) is an international meeting of botanists in all scientific fields, authorized by the International Association of Botanical and Mycological Societies (IABMS) and held every six years, with the location rotat ...
, which stated that the first specific name must be used. Of these names, the
Integrated Taxonomic Information System
The Integrated Taxonomic Information System (ITIS) is an American partnership of federal agencies designed to provide consistent and reliable information on the taxonomy of biological species. ITIS was originally formed in 1996 as an interagenc ...
recognizes only ''Persea pubescens'' as a synonym for ''Persea palustris'', as well as ''Persea borbonia'' var. ''pubescens'' (given by
Elbert Luther Little Elbert Luther Little, Jr. (born October 15, 1907, in Fort Smith, Arkansas; died June 23, 2004) was an American botanist whose career spanned 70 years and largely concerned forest botany. Although he was born in Arkansas, and died in Oregon, he grew ...
) and ''Tamala pubescens'' (given by
John Kunkel Small
John Kunkel Small (January 31, 1869 – January 20, 1938) was an American botanist.
Born on January 31, 1869, in Harrisburg Pennsylvania, Kunkel studied botany at Franklin & Marshall College and Columbia University. He was the first Curator of ...
). It is also referred to as swamp bay and swampbay.
Distribution and habitat
''Persea palustris'' is distributed throughout the
Southeastern United States
The Southeastern United States, also referred to as the American Southeast or simply the Southeast, is a geographical region of the United States. It is located broadly on the eastern portion of the southern United States and the southern por ...
and the Bahamas, found in eleven different US states, from Delaware to
Southeast Texas.
Its range heavily overlaps with that of the ''Persea borbonia''.
It is common throughout Florida, including the
Florida Keys
The Florida Keys are a coral cay archipelago located off the southern coast of Florida, forming the southernmost part of the continental United States. They begin at the southeastern coast of the Florida peninsula, about south of Miami, and e ...
.
It is also common in costal plain regions of North Carolina.
Its natural habitat includes swamps, bays,
pocosins, costal
swales, and
maritime forest
A maritime forest is an ocean coastal wooded habitat found on higher ground than dune areas within range of salt spray. They can be found along the Atlantic and Pacific Northwest coasts of the United States. They can also be found in areas of So ...
s, particularly in wet,
peaty
Peat (), also known as turf (), is an accumulation of partially decayed vegetation or organic matter. It is unique to natural areas called peatlands, bogs, mires, moors, or muskegs. The peatland ecosystem covers and is the most efficient c ...
soil, although it can also grow in dry, sandy soil.
Conservation
Laurel wilt
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 membe ...
is a significant danger to ''Persea palustris''. It is caused by the
fungus
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from th ...
''Raffaelea lauricola'', which is spread by the
redbay ambrosia beetle
''Xyleborus glabratus'', the redbay ambrosia beetle, is a type of ambrosia beetle invasive in the United States. It has been documented as the primary vector of ''Raffaelea lauricola'', the fungus that causes laurel wilt, a disease that can kil ...
, a nonnative species introduced to the United States (other species of
ambrosia beetle
Ambrosia beetles are beetles of the weevil subfamilies Scolytinae and Platypodinae ( Coleoptera, Curculionidae), which live in nutritional symbiosis with ambrosia fungi. The beetles excavate tunnels in dead, stressed, and healthy trees in wh ...
can also carry it, but at lower levels). While laurel wilt affects other members of
Lauraceae
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 (Christenhusz & Byng 2016 ). They are dicotyledons, and occur ma ...
, swamp bay is particularly sensitive.
It is more resistant to
gall
Galls (from the Latin , 'oak-apple') or ''cecidia'' (from the Greek , anything gushing out) are a kind of swelling growth on the external tissues of plants, fungi, or animals. Plant galls are abnormal outgrowths of plant tissues, similar to be ...
s (swelling growths) than ''Persea borbonia''.
References
{{Taxonbar, from1=Q1245407, from2=Q87637841
palustris
Trees of the Bahamas
Trees of the Southeastern United States