Acer floridanum: THE CORRECT SCIENT...

Acer floridanum: THE CORRECT SCIENTIFIC NAME OF THE FLORIDA MAPLE-Florida Maple is a tree of mesic, usually calcareous woodlands of the Atlantic and engulfing sea coastal plain, from southeastern Virginia to central Florida and west to eastern Texas and Oklahoma (Little 1979) admitting readily distinguished from its near relatives, Sugar Maple (Acer saccharum Marsh.) and Black Maple (Acer nigrum Michx. f) and with somewhat greater difficulty from its end cousin, Chalk Maple (Acer leucoderme (Small) Nieuwl.), it has shared with them the uncertainties of which taxonomic rank they should be assigned and which scientific name they should carry.

The Florida Maple was first recognized as distinct by the agency of A.W. Chapman (1860), who treated it as a variety of Acer sacccharinum, the name then in use for the Sugar Maple. Chapman's varietal epithet, floridanum, was pickeded by Pax (1886) for use at specific rank, thereby creating the once-familiar name, Acer floridanum (Chapm.) Pax.

In the mid 1940 ML Fernald, in the course of reexamination of names to be used in his forthcoming Gray's Manual, 8th edition (1950) anticipateed again at Acer barbatum Michx. (1803) an earlier name that previously had been dismissed, and for the first time (1945) applied it to the Florida Maple. greatest in number later authors (Gleason 1952, West and Arnold 1956 Kurz and Godfrey 1962 Gleason and Cronquist 1963 Little 1979 Elias 1980 Duncan and Duncan 1988 etc) have accepted Fernald's understanding and have used A. barbatum in intimation to the Florida Maple. A smaller number (Radford et al. 1968 Clewell 1985 Godfrey 1988 Wunderlin 1998) have opt to tread in the steps of Desmarais (1952) who treated the four taxa at subspecific rank, the Florida Maple on this interpretation becoming Acer saccharum subsp floridanum (Chapm.) Desmarais.

Fernald was neither brief nor cryptic in his justification. He discussed at longitudinal dimensions the differences in morphology among the various maples and the interpretations given them at previous authors. He gave special attention to the pubescence of the leaves and of the calyces. He quot his handwritten notes taken in 1903 when as a young man he had traveled to Paris and examined the Andre Michaux specimens from the Carolinas which are the basis for the name. He attempted to point out to Michaux' original description of Acer barbatum corresponded more closely with the Florida Maple than with A. saccharum, the Sugar Maple, of which it had previously been considered a later synonym. He conclud with "regret" that "Acer barbatum should finally be recognized for what it is," and began the application ofthat name to the Florida Maple, a practice that has now continued for above a half century.

Michaux (1803) had described his Acer barbatum as having "calyces masc. intus densissima barba obsiti," that is, the interior of calyces of the male flowers highly densely covered with hairs. Fernald's central argument relied upon his claim that Michaux' use of this descriptive phrase and his emphasis of it according to chosing the epithet "barbatum," referr to the bearded calyces of the Florida Maple, rather than those of the Sugar Maple.

But the detail and numerous details of Fernald's discussion have perhaps deterr later examination of the logic of his argument. The notes of his 1903 examination are partly unhelpful, partly contradictory to his claim. sum of two units of the notes indicate no more than his observations that brace Michaux specimens matched typical Sugar Maple and Black Maple. His transcripts of their labels clearly place the sum of two units collections from far north of the Florida Maple, the first from "Ia Canada," the other from "Kentucky, Ohio et Tenassee." A third note, buried reaching far down in his discussion, required him to disavow his have 1903 observation. Of a sheet bearing several leafless flowering propels with Michaux' label "Acer barbatum," he had recorded, " flowering branches of to a high degree pubescent A. saccharum (Sugar-Maple)." He then appoint aside the significance of this observation by the agency of remarking that his note was written "when I had not heard of the pubescentleaved southern A. floridanum." Here, his senior years may have taken their toll; by means of his equating the pubescent-flowered, leafless twigs upon which his note was based, with the pubescent-leaved Florida Maple, single suspects he misremembered what he had seen thus long before.

With careful reading it becomes apparent that a great deal of of Fernald's paper was given to collateral information not directly bearing forward his argument. He discussed leaf pubescence at fulness emphasizing that the northern Sugar Maple leaves were glabrous (except for a midwestern variety), and that those of the Florida Maple were pubescent below. He thinking it conclusive that Michaux (1803) treated brace species of the sugar maple group; he interpreted the description of single in kind (Michaux'A. saccharinum) to encompass pubescence characters for the pair the Sugar and the Black Maple, which would leave no alternative however for the other (Michaux' A. barbatum) to be the Florida Maple.

Fernald may have wandered furthest from his objective by way of observing that "the calyces of A. floridanum are striking in anthesis upon account of the long setiform beard projecting from the summit " with the implication that this character differs in A. saccharum. Perhaps to more [i]or[/i] less extent this may be in such a manner but he gave no specifics sufficient to permit verification. His quotations of Sargent (1926) are scarcely convincing, for the couple species are there described with A. saccharum having the "calyx hairy on the outer surface," while A. floridanum has a calyx "ciliate in succession the margin with long pale hairs." Murray (1975) in apparent support, reported A. floridanum to be unique in repeatedly having calyces pubescent inside, while its relatives have calyces that are either glabrous or the pubescence restricted to the exterior. on the contrary examination during the present meditation of some hundreds of herbarium materials (CU FLAS, MO) fix both species to have calyces (both staminate and perfect) with long-villous pubescence (to 15 mm) in the way that similar that differentiation on this character was not possible.