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Balduina uniflora
Balduina uniflora, commonly called oneflower honeycombhead,[2][3] savannah honeycombhead[4] or oneflower balduina,[5] is a North American species of plants in the sunflower family. It is native to the southeastern United States (Louisiana, Florida, Georgia, Alabama, Mississippi, South Carolina, North Carolina).[6] It is the type species of the genus Balduina.[7] Balduina uniflora is a perennial herb with branching stems. Each plant has 1-4 flower heads, each with 8-22 yellow ray florets and 50-180 orange or yellow disc florets. The species grows in wet pinelands[4] and savannahs,[8] as well as wetland areas and on the edges of bogs[7][2] and tends to occur in wet drainage ditches and on roadsides.[4] DescriptionBalduina uniflora is a perennial herbaceous plant and can grow to be 0.4 to 1 meter tall.[7][3] It has fibrous roots and erect stems, and the stems are ribbed.[4] Stems also tend to be branched, except for those that bear flower heads.[7] Leaves, stems, involucres, and peduncles are green and pubescent, except for the bottoms of leaves which may be glabrous or with only sparse hair.[9] Leaves are alternate and tend to be clustered at the base of the plant, getting smaller and more sparse as they reach the apex.[9]  Like other members of family Asteraceae, the "flowers" of this species are actually inflorescences called flower heads, composed of hundreds of individual flowers.[10] The inflorescence has many bracts at its base forming a green bell-shaped or hemispheric involucre.[11] The yellow petal-like ray florets are sterile and tend to have 3-5 lobes at the edge.[11] The more central disc florets are perfect, containing several arrow-shaped stamen as well as a pistil made up of two ovaries.[7] Each pistil has a yellow[9] two-branched style which extends out of the floret.[7] The plant gets its name from characteristic honeycomb-like bract structures (chaff[11]) most visible at fruit maturity.[7] Also like others in the Asteraceae family, B. uniflora bears achene-like cypselae: dry, indehiscent fruits with a single seed that develops from the two carpals of the flower.[9][10] This fruit is generally 1.3-2.2mm in length.[9] This species differs from others in the genus Balduina by its wider corolla rays,[7] larger pollen grains,[7] and by having chromosome arrangement of n=36 rather than n=18 in other species.[7] CultivationBalduina uniflora is not usually a commercially available species, but may be grown from seeds for ornamental purposes in native wildflower gardens.[4] The species prefers wet and boggy soils as well as high levels of sunlight.[4] Possible polyploidyA 1975 study of Balduina conducted by Earl S. Parker and Samuel B. Jones[7] found a chromosomal arrangement of n=36 in B. uniflora collected across 16 different areas, which differed from the n=18 arrangement of the other two species in the Balduina genus, leading to the theory that the species is a widespread polyploid.[7] No assumptions as to whether this chromosomal arrangement was allopolyploid or autopolyploid in origin were made.[7] EcologyBalduina uniflora is currently not listed by the IUCN Red List.[12] This species is listed by the NatureServe organization as "Apparently Secure (S4)" nationwide,[5] but as "Vulnerable (S3)" and "Imperiled (S2)" in North and South Carolina, respectively.[5] This species is not known to be invasive in any U.S. State.[2] References
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