Monographs Details:
Authority:

Sargent, Charles S. 1889. Vaccinium hirsutum. Gard. & Forest. 2: 364, 365, fig. 119.
Family:

Ericaceae
Scientific Name:

Vaccinium fuscatum Aiton
Description:

Species Description - Plants usually crown-forming, or sometimes in small colonies, 1.5-3 m. high. Leaves coriaceous, evergreen to subpersistent (in some closely allied forms deciduous), usually deep green, but sometimes subglaucous; the lower surface nonglandular and pubescent on the veins, or sometimes glabreseent or quite pubescent; lanceolate to narrowly or broadly elliptic (a related form is basally cordate), 1.5-2.5 cm. wide, 3.5-5 cm. long; the margin entire, but occasionally subserrate. Corolla urceolate, 7-9 mm. long, usually deep pink or even almost red. Fruit generally dark, but may be dull or even subglaucous, 6-10 mm. in diam., usually of poor flavor.

Discussion:

V. formosum Andr. Bot. Rep. 2: pl. 97. 1800.

V. fuscatrum var. pullum Ashe, Rhodora 33: 196. 1931.

Cyanococcus fuscatus Small, Man. SE. Fl. 1013, 1506. 1933.

Cyanococcus holophyllus Small, Man. SE. Fl. 1015, 1507. 1933.

V. holophyllum (Small) Uphof, Mitt. Deuts. Dendr. Ges. 48: 19. 1936.

Probably tetraploid.

At first glance the almost bewildering array of material which seems to be in some way associated with V. fuscattum would appear to be even more complex than that of the northern highbush V. corymbosum. However, running through the population is a form with relatively narrow, lanceolate-elliptic leaves which are non-glandular, entire, subpubeseent, fairly coriaceous, and essentially evergreen. Also, scattered here and there are similar, but smaller plants which could be little else than hybrids between atrococcum and darrowi. The larger plant, here treated as V. fuscatum, appears to be an allopolyploid derived from the diploid hybrids. It would, of course, be possible to suppose that fuscatum could be the result of "blended" and semistabilized segregates following myrsinites x australe and myrsinites x arkansanum combinations. However, these are known, but do not seem to fit into the basic element of fuscatum, which is typically nonglandular, whereas the others only occasionally segregate evergreen, non-glanldular forms. The basic element of fuscatum has a rather consistent appearance and distribution and would likely cause little trouble in identification were it not for the presence of other species in parts of its range which seem to have hybridized with it.

The chroinosome complement of this basic element of fuscatum is unknown, but the following may be noted: In northern Florida and southern Georgia, plants are known which are intermediate between fuscatum and australe, being fairly good miatches for the original illustration of V. formosum. In fact the apparent influence of fuscatum may occasionally be seen in the population of australe as far north as South Carolina by noting those plants with slightly coriaceous (but deciduous) leaves and with pink-tinged flowers. Also, in parts of F'lorida, the leaves of fuscatum are less coriaceous, often only subpersistent, and inclined to be somewhat larger and more pubescent than those of the basic element; these would appear to be the result of gene-exchange with arkansanum. And throughout the range of fuscatum, numerous plants are found which could scarcely be anything else except hybrids between it and myrsinites. Since there is every reason to believe that arkansanum is tetraploid, and both australe and myrsinites are known to be, it is concluded that the basic element of fuscatum, as here defined, is also tetraploid. Occasional plants ill north Florida and south Georgia with gland-bearing, subserrate, and tardily deciduous leaves seem to be segregates of fvuscatum x virgatum. The leaves of what appear to be the F1 plants of myrsinites x arkansanum are usually less coriaceous than those believed to be myrsinites x fuscatum; certain of the segregates and back-crosses of these combinations would be most difficult, if not impossible, to separate.

For the purpose of stabilizing our concepts, and as a basis for future work on the complex, the circumscription of fuscatum has been limited so as to include only plants whose leaves were evergreen, or at least subpersistent, were above a certain size, whose lower surfaces were non-glandular and bore at least a slight amount of pubescence. It was only by this method that one can be reasonably certain of excluding the possible diploid hybrids between atrococcum and darrowi and the hybrids of myrsinites x arkansanum, myrsinites x atstrale, and myrsinites x futscatum. The lines between fuscatum and the segregates of fuscatum x australe and fuscatum x arkansanum combinations are more difficult to draw and must remain a matter of judgment.

For the present, there is no intention of naming even the more easily recognizable of the various hybrid and segregate forms present in what may be called the southern tetraploid hybrid complex, although some of the segregates appear to have been partially selected and occasionally to have built up somewhat homogeneous local populations. By defining fuscatum in the preceding manner it is felt that the way has been opened for a better understanding of the many problems presented by the closely integrated population which appears to reach its maximum complexity within a radius of 75 miles of Jacksonville, Florida. Individual localities outside this area present their own minor probleius; the presence usually of fewer species in them has not permitted the production of such complex populations.

There are perhaps some items in the synonymy of this species which should be noted. In the original description of V. formosum it is said that: "this species of Whortle-berry was first introduced (according to the Kew Catalogue,) in 1770, by Mr. William Young, from N. America. . . ." Under his description of V. fuscatum var: p'allum, Ashe says: "The plate of V. formosum Andr. . . . which refers to Aiton's description of the same cultivated plant upon which V. fuscatum is based. . . .." He thereby implies that they were based on the same material. However, the original description of V. formosum says "foliis . . . glabris," whereas that of V. fuscatum says "venis subtus villosiusculis." It is of further interest to note that the specimen checked by Dr. Smith (see footnote 2) as duplicating the type of V. fuscattm is by no means an exact match for the plate of V. formosum, although it does have certain similarities. While it is possible that the aspect of the plant from which the plate of V. formosunm was taken is a seasonal growth phase of the original clone of V. fuscaturm under cultivation, it is also possible that it represents an additional introduction which, because of its somewhat similar characteristics was included in fuscatum by the nurserymen of the time. The original plate of V. formosum, together with the description, makes it a close match for plants which I take to be segregates of ftuscatum x australe; hence it is perhaps not strictly a synonym of fuscatum as here interpreted, but a closely allied form which would be included in a broad interpretation of the species. I have not been able to locate the type of Ashe's var. pullumn, but it seems to belong here, although the notes indicate that it may be a plant similar to those thought to be segregates of ftscatum x myrsinites. The two "types" of Cyanococcus holophyllus, while differing from each other, fall within the general variability of fuscatum.

Distribution:

United States of America North America|