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 4°C). 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%). For fertilizer studies, seeds were planted in soilless mix with no fertilizer, liquid fertilizer (20–20–20 at 1.25 g/L water), or solid fertilizer (14–14–14 slow release at 14.6 g/L mix) in growth chambers. After 7 wk, shoot fresh mass, leaf number, leaf area, crown diameter, root length, and shoot dry mass were measured. Seedling growth was greatest with solid fertilizer compared to control and liquid fertilizer, which were similar. Overall, hickory solution at 1:100 with light produced the highest percent germination among all treatments, and solid fertilizer was most effective for transplant development. These findings are useful for management or restoration of P. tubaeflorus populations.

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. In the lowland, wetter forest communities, Tsuga canadensis was the dominant species at both time periods; however, in the 1950's, Fagus grandifolia was an important subdominant species, but by 2010, this species was not recorded in this forest type at Bear Creek. There has been a shift in the forests at Bear Creek in the 6 decades since Donahue's survey. In that time, beech bark disease was reported in Pennsylvania, and deer browsing was noted as having a major impact on tree regeneration.

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 sandier soils. These species occur at NB66 but the forest remains dominated by native offsite species, which are aggressively reproducing. These offsite species formerly occurred in less elevated landscape positions in association with magnolia-beech and bottomland hardwood forests. Frequently burned old-field pineland adjacent to NB66 has remained stable indicating that no factors other than fire exclusion caused release of hardwoods from their “fire trap.” There was no trend toward recovery of the original SPOH community, and forest development is postulated on the basis of mesophication processes. Recruitment of new species—both woody and herbaceous—since 1966 was modest; most remain uncommon.

The reproduction and ecology of the narrow endemic and Florida endangered shrub Hypericum edisonianum (Edison's St. John's Wort) was investigated through field and greenhouse studies. Hypericum edisonianum exhibits a number of traits common to rare and geographically limited plant species including heavy reliance on clonal propagation to maintain local stands, passive seed dispersal resulting in a near-parent seed shadow, limited numbers of genetically unique individuals in its isolated seasonal-pond habitat, and likely self-incompatibility. In the field study, most flowers were produced by a small subset of the monitored ramets. Indeed, three ramets belonging to a single genetic individual accounted for 26% of all seed output from the 78 ramets monitored over a one-year period. In spite of strong seed production and germination, seedling establishment appears to occur episodically. The implication is that H. edisonianum is poorly equipped to withstand landscape drainage, agricultural and human development, and climate change. Such impacts will severely challenge the persistence of not only H. edisonianum but also many of the associated species inhabiting Florida scrub. Detailed information is needed about the population-genetic structure of H. edisonianum populations in order to understand its metapopulation structure. Protection of existing and potential H. edisonianum stands is crucial to the long-term preservation this species.

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 duration for some physiological parameters, suggesting the ability of these plants to adapt to changing climatic conditions. Further experimentation is needed to determine the effects of reduced cloud immersion on plant fitness.

Piedmont Gabbro Upland Depression Forests are a globally imperiled (G2) association endemic to a few scattered locations in the Piedmont regions of Georgia and South Carolina. These distinctive communities occur in relatively level uplands over mafic shrink-swell clays, particularly Iredell soils, derived from gabbro bedrock, and the hydrology ranges from seasonally saturated to very dry. These sites support unusual assemblages of plants including species typically associated with wetlands, xeric areas, and the Coastal Plain. A vouchered floristic inventory was conducted of three sites (270 ha; 666 ac) in Oconee National Forest in Jasper County, Georgia. The survey documented 541 vascular plant species (and eight varieties) in 319 genera and 111 families. The 86 exotic species comprise 15.9% of the flora. According to state rankings, five rare plant species occur within the study area, including Quercus oglethorpensis (state-ranked threatened). Herein, we provide an annotated species list and maps, descriptions, and photographs of the study site.