Volume 79 - Issue 3 (Sept 2014)

Physiological Response of Southern Appalachian High-Elevation Rock Outcrop Herbs to Reduced Cloud Immersion

ABSTRACT Cloud immersion experienced by high-elevation rock outcrop plants reduces the leaf-to-air vapor pressure deficit (VPD), decreasing transpirational water loss. Frequent cloud immersion might ameliorate water stress in shallow-soil outcrop communities, increasing water use efficiency and growth. Current climate pattern predictions propose that Southern Appalachian cloud immersion frequency will decrease, potentially increasing water stress in rock outcrop plant populations. In this experiment, outcrop specialists Hydatica petiolaris (cliff saxifrage) and Solidago simulans (granite dome goldenrod) were grown in microcosms simulating current, reduced, and absent cloud immersion. Maximum photosynthetic rates, light saturation point and water use efficiency (WUE) increased, and transpiration decreased with decreasing immersion duration. Root mass, root-to-shoot ratio, and specific leaf mass were greatest in the reduced immersion treatment. Simulating nonimmersed abiotic conditions while measuring gas exchange in a leaf cuvette resulted in higher VPD, photosynthetic rate, transpiration, and lower WUE across treatments. Results indicate acclimation in response to immersion

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Forest Development 44 Years after Fire Exclusion in Formerly Annually Burned Oldfield Pine Woodland, Florida

Young mixed hardwood forest communities that colonized abandoned croplands during the late 19th century in northern Florida were typically winter burned annually after pine saplings could survive fire. Hardwood trees persisted as coppice that grew from root crowns within grassy undergrowth. This plant community changed little thereafter, except for the continued growth of pine trees. An 8.64-ha tract of this community was inventoried in 1966, from which fire was permanently excluded thereafter. This tract, called NB66, was reinventoried in 2010 to document maturation of the plant community and to identify the contributing causes that controlled ecological development. Hardwood coppice that was released from fire grew to form a nearly continuous canopy averaging 19.7 m high after 44 years. Many older pines died and disintegrated without causing canopy gaps. Prior to 19th century plantation agriculture, the original vegetation consisted of shortleaf pine-oak-hickory (SPOH) woodland, which intergraded with longleaf pine savanna on

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Long-Term Forest Changes in Northeastern Pennsylvania

ABSTRACT The forest communities of northeastern Pennsylvania are diverse due to variation in climate, geologic history, soil types, and topography. This research specifically surveyed the forest communities of the Bear Creek region of southeastern Luzerne County, Pennsylvania. The purpose of this study was twofold: (a) to document the current forest community composition and to compare the forests of today to the last known forest survey in this area completed by Donahue in the early 1950s; and (b) to propose explanations for the differences observed between the two survey periods. The upland forest community surveyed by Donahue was dominated by red maple (Acer rubrum) and oaks (Quercus alba and Quercus rubra), with these three species accounting for 78.4% of all stems recorded. In contrast, the contemporary upland forest is now dominated by oaks (Q. alba and Q. rubra), with a subdominant layer composed of Acer saccharum, A. rubrum, and Sassafras albidum.

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Investigation of Seed Treatments and Fertilizer on Growth of Penstemon tubaeflorus

ABSTRACT Penstemon tubaeflorus is a North American prairie forb of conservation concern. Protocols for seed germination and transplant production involving fertilization are needed for conservation purposes. Our objectives were to compare techniques for breaking seed dormancy and increasing germination, and to investigate fertilizer on growth of Penstemon tubaeflorus. Seed treatments were hickory smoke seasoning solution (1:10, 1:100, 1:500, and 1:1,000), light vs. dark, prairie plant ash solution (2, 4, 8, and 16 g/L), and cold moist stratification (1 or 2 mo at 48C). Seeds were germinated in Petri dishes in germination chambers and counted for 21 d. For hickory solutions, 1:100 had the highest germination (51%), and seeds germinated in light, but not in the dark. For ash solutions, 8 g/L (6%) and control (4%) germinations were higher than 2 g/L with 4 g/L and 16 g/L being intermediate. Germination increased for both stratification durations (37%) compared to control (2%).

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2014 Richard and Minnie Windler Award Recipients

Systematics—Lisa E. Wallace and Christopher H. Doffitt Ecological—Donald G. Ruch, Byron G. Torke, Kemuel S. Badger, John E. Taylor, Benjamin R. Hess, and Paul E. Rothrock The Richard and Minnie Windler Award recognizes the authors of the best systematic botany paper published in Castanea during the previous year. For 2013, authors of two papers were selected as winners: Lisa E. Wallace and Christopher H. Doffitt for their work entitled ‘‘Genetic Structure of the Mesic Forest-Adapted Herbs Trillium cuneatum and Trillium stamineum (Melanthiaceae) in the South-Central United States’’ (Castanea 78[2]:154–162) and Donald G. Ruch, Byron G. Torke, Kemuel S. Badger, John E. Taylor, Benjamin R. Hess, and Paul E. Rothrock for their work entitled ‘‘The Vascular Flora and Vegetational Communities of Cabin Creek Raised Bog, Randolph County, Indiana’’ (Castanea 78[4]:290–311; Figure 1). Wallace and Doffitt’s project was undertaken to determine if landscape features, such as large rivers or prairies, influence the genetic structure

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2014 Elizabeth Ann Bartholomew Award Recipient — Thomas Wentworth

Dr. Thomas Wentworth, Professor of Plant Biology at the North Carolina State University, received the Elizabeth Ann Bartholomew Award on 4 April 2014 at the annual meeting of the Southern Appalachian Botanical Society (SABS), held in Spartanburg, South Carolina. This annual award honors the memory of Elizabeth Ann Bartholomew’s untiring and unselfish service to SABS, professional botanists, students, and the public. The highest honor given by the Society, this award is presented to individuals who have distinguished themselves in professional and public service that advances our knowledge of the world of plants and their scientific, cultural, and aesthetic values. Dr. Wentworth fits right into the ideals that Betty set. He has years of dedicated service in teaching and professional service toward the betterment of botany and ecology of the southeastern United States. ‘‘Tom’’ has more than 30 years of classroom teaching experience. He has taught numerous courses, including his most

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