Volume 62 – Issue 4 (Dec 1997)

The vascular flora of a predominantly forested tract which includes floodplain and terrace of the Tombigbee River and some adjacent hills and ravines in northeastern Choctaw County, Alabama, was surveyed during 1994 to 1996. The mature mixed-oak bottomland forest portion of the study area included ten 2 to 3-year-old small harvested openings, each opening a rectangle of about 0.32 ha (0.8 ac). In the survey, 450 vascular plant species representing 293 genera in 111 families were collected. Of these, 271 species appear to represent new collection records from Choctaw County. The harvested patches, which were representative of a group selection silvicultural system, retained most of their preharvest species while allowing establishment of 35 species not found elsewhere in the study area.

Orchids are fabulous plants that always attract attention. There are numerous temperate species (with Florida, the Great Lakes region, and the Carolinas having the largest numbers) and countless species in the tropics. The Orchidaceae are probably the largest plant family, with some 19,500 species. They are the subjects of a tremendous horticultural interest, with thousands of amateur and professional growers around the world. I would guess there are more books on orchids, both wild and cultivated, than any other category of plant subject.

If you are in the woods, look about and you will probably see a maple. If you are in an ornamentals garden, you should also be able to see a maple. Maples are comfortably familiar to us all; they are characteristic of the north temperate zone throughout the world. They occur in almost every terrestrial habitat, often as indicators of a vegetation type; and provide educational examples of interesting distribution patterns. For example, if you are acquainted with our eastern North American species you know that Acer rubrum is extremely widespread and may be found in virtually any habitat, while A. leucoderme has a very narrow Southeastern piedmont distribution on dry river bluffs.

Noteworthy Collections: South Carolina and Kentucky

Schwalbea americana L. (Scrophulariaceae) “American Chaffseed” is a rare, caulescent, root parasitic herb of moist pine flatwoods, sandy oak woods and pinelands, savannahs, and ecotonal areas between peaty wetlands and xeric sites (Kral 1983). Schwalbea is apparently intolerant of shade and benefits from the removal of woody understory vegetation and canopy trees (Musselman and Mann 1978, Peters 1994, Town send 1995). Both frequent fires and mechanical vegetation removal maintain this habitat, which is necessary for the species’ survival (Peters 1994, Porcher 1994, Townsend 1995). Schwalbea is apparently intolerant of shade and benefits from the removal of woody understory vegetation and canopy trees (Musselman and Mann 1978, Peters 1994, Townsend 1995).

Congratulations, Ed, on the publication of volume three of your Michigan Flora. It certainly is a clich6 to say it is “long awaited.” You’ve been working on the Flora for almost 50 years, the first volume of which appeared in 1972. I used it as a student; but, alas, could not wait for the subsequent parts before leaving Michigan. I have kept up with your progress, and have been impressed to learn that you personally examined some 250,000 herbarium specimens in many herbaria in several states looking for Michigan records.

Rhynchospora harperi Small, sometimes synonymized with R. filifolia Gray, is here regarded as a distinct species. It is distinguished from R. filifolia primarily by achenal features. Historically known only from Florida, Georgia, and Alabama, R. harperi now is also known to occur in South Carolina, North Carolina, Maryland, and Delaware; and in Belize, Central America.

Growth chamber experiments examined the effects of salinity on seed germination and seedling growth of Solidago sempervirens var. mexicana. Seeds were germinated at salinities ranging from 0-3% (weight/volume). Germination rate and percentage decreased with increased salinity. Seeds exposed to full strength (3%) sea water for 1-10 days and subsequently removed to fresh water gave 45-60% germination regardless of their length of exposure to sea water. Length of time in salt water affected the rate of germination; seeds exposed to sea water for 6-10 days germinated more rapidly than did seeds exposed for shorter periods. Seedlings subirrigated with 0-3% salt solutions showed optimum growth at 1% salinity, with decreasing growth and increasing succulence at salinities >1%. Despite addition of a dilute nutrient solution to all treatments, seedlings irrigated with freshwater only were slightly chlorotic. Responses of Solidago sempervirens to salinity indicate adaptation to oceanic dispersal and subsequent establishment in saline habitats, both of which may contribute to its wide geographic distribution.

Native and non-native vascular plants at Fisherman Island, Virginia, collected in 1975-76 by Boule were compared with the 222 taxa collected in the floristic survey of 1993-1995 by Stalter and Lamont. In contingency table analysis of log-likelihood, the frequency of non-native vascular plants within the highly disturbed ruderal plant community at Fisherman Island is highly significantly greater (64.7%, G = 59, 1 df, P < 0.0001) than at the sand dune, salt marsh, immature maritime forest, and swale (0%, 3.5%, 2.9%, 23.9%, respectively), where human disturbance is minimal. There is a highly statistically significant difference between the pattern in which native species versus non-native species sort themselves out across the five communities (G = 82, 4 df, P < 0.0001). The overall percentage of 20.1% for non-native vascular taxa at Fisherman Island in 1975-76 collected by Boule is not significantly different from the overall percentage of 22.1% for non-native vascular plants collected in this study (G = 0.19, 1 df, P = 0.66).

The extent of forest, savanna, barrens, and prairie vegetation of Crawford County, Illinois, was mapped using the General Land Office survey notes of 1804-1821. Forest vegetation was the most extensive, covering 40.8% of the county, followed by prairie (34.2%), savanna (18.2%) and barrens (6.8%). Quercus alba L. (white oak) was the dominant forest species with an importance value (IV) of 60.6, followed by Q. velutina Lam. (black oak), Carya spp. (hickories), Ulmus spp. (elms), and Acer saccharinum L. (silver maple). In the savanna white oak again dominated (IV of 66.2), followed by black oak and hickories. The areas designated as barrens by the surveyors were dominated by white oak (IV of 78.8) followed by hickories, black oak, Acer saccharum Marsh. (sugar maple), and Fagus grandifolia Ehrh. (beech). Density (trees/ha) was 149.7, 18.2 and 29.7 for the forest, savanna and barren areas, respectively. Corylus americana Walt. (hazelnut) had the highest frequency for understory shrubs and was commonly associated with the forest prairie interface and barrens.