Vegetative filter strips have been adopted as a common best management practice to manage soil erosion and nutrient losses from cultivated fields. New species and combinations of species are constantly being assessed based on their riparian function. A unique species that is native to southern Illinois and the southeast is giant cane (Arundinaria gigantea). Giant cane's performance as an effective filter of sediment and nutrients from surface and subsurface flows has been recently documented; however, it can be difficult to establish in riparian zones. Therefore, the purpose of this study was to evaluate a new approach for restoring giant cane in riparian buffer zones and methods that provide quick protection of critical source areas in the field. This study focused on developing a low-cost method for giant cane restoration designed to give reproductive propagules an advantage in assembling a successful canebrake while protecting critical areas bordering agricultural fields and streams/ditches. To achieve this goal, three types of sandbags (polypropylene, treated burlap, and nontreated burlap) were used as growing containers for giant cane rhizomes. Additionally, two soil mixtures and a fertilizer treatment were assessed for their influence on cane emergence, survival, and growth. Results showed that the nontreated burlap/mixed soil-media/no-fertilizer combination provided the best growing environment for newly established giant cane rhizomes. This combination provided sufficient soil moisture and bag permeability to cane. Overall, a 90% success rate for emergence, and 30% survival rate over the growing season was observed using nontreated burlap/mixed soil-media/no-fertilizer.

The Oakmulgee District of the Talladega National Forest is the largest remnant of the endangered longleaf pine (Pinus palustris) ecosystem in Alabama. A partial floristic survey using nested plots and survey plots was conducted May–July 2016 in longleaf pine woodlands of the Oakmulgee District that were differentially impacted by a 27 April 2011 EF3 tornado and a subsequent salvage harvesting operation. Vascular plants were identified and ranked by frequency of occurrence (rare, occasional, common, and abundant) in three disturbance categories: undisturbed, wind-disturbed, and compound-disturbed (wind-disturbed and salvage-harvested). Overall, 192 plant taxa in 68 families and 137 genera were documented. Plant taxonomic richness was lowest on undisturbed sites (90 taxa), greatest on wind-disturbed sites (160 taxa), and reduced on compound-disturbed sites (126 taxa). Although salvage harvesting reduced taxonomic richness, 46 of the 48 plant taxa unique to unharvested wind-disturbed sites were rare (occurred on <10% of nested plots). Moreover, undisturbed sites had only nine unique taxa, of which eight were rare. Decisions on whether to salvage harvest must consider the ecological significance of these rare plants. Wind- and compound-disturbed areas may recover toward predisturbance conditions, and the floristic list presented here provides the baseline to monitor this succession. The documented floristic composition also provides insight on short-term responses of vascular plants to differential disturbance impacts in an understudied region of the longleaf pine ecosystem.

Two similar species of Primula section Dodecatheon are native and rare in Pennsylvania: Primula meadia in the Potomac watershed and Primula fassettii (syn. D. amethystinum), in the Susquehanna watershed. In the field, P. meadia is more robust than P. fassettii in most features. We conducted a common garden experiment to determine whether P. fassettii would more nearly resemble P. meadia. We collected seeds from one field site in both watersheds in 2008. Plants were grown in a greenhouse at Mt. Cuba Center, Delaware, until 2011, then in raised beds in a shade house. The first plants bloomed in 2012, and almost all bloomed in 2013 and 2014. We gathered data on 22 characteristics through 2014. The two populations exhibited statistically significant convergence in the common garden (less difference than in the field) in leaf length and length-width ratio, flower number, and capsule wall thickness. Significant divergence (more difference than in the field) occurred in scape diameter, corolla color, and capsule shape and color value. The remaining characters did not converge or diverge: leaf width, leaf base coloration, scape length, calyx lobe length, corolla length, calyx:corolla length ratio, anther length, and anther color, as well as capsule length, width, length-width ratio, valve length, hue, and chroma. In common garden (compared to field) scape dimensions, flower number, capsule dimensions, and capsule wall thickness increased while calyx lobe length decreased. Corolla and anther length did not change. Corolla color was significantly darker in Susquehanna plants, while capsule hue became more reddish in both populations.

Two species of Mazus (Mazaceae) are naturalized in North America, Mazus pumilus and Mazus miquelii. A new guide for distinguishing these species is provided. Comparisons of North American plants with the type specimen of the name M. miquelii and with specimens from the native range of that species support the inclusion of the naturalized plants sometimes called Mazus reptans in M. miquelii.

The phylogeny of closely related species of Isoëtes has been difficult to infer using morphological or molecular data. The southeastern United States exhibits among the highest diversity of Isoëtes species, which likely are the result of a relatively recent radiation. We used whole chloroplast genome (plastome) sequences to infer a phylogeny of diploid taxa in the Southeast. The phylogeny of the entire plastome was well supported across various models of evolution. Separate phylogenetic analyses of coding regions and introns mostly returned the same tree topology as the whole plastome, although the placement of four species was discordant. The plastome phylogeny highlights taxonomic issues, because two pairs of infrageneric taxa are resolved as polyphyletic. Inference of ancestral character states suggests a common ancestor of the southeastern clade with white, tuberculate megaspores and papillose microspores maturing in the spring. This study is the first to resolve molecular-phylogenetic relationships in diploid Isoëtes from the southeastern USA and shows the utility of plastome sequences for unraveling relationships between closely related taxa.

A floristic survey was conducted of Crowders Mountain State Park for all vascular species from 2010–15. Crowders Mountain State Park was established in 1974 to protect a geologically unique North Carolina Piedmont site. In addition, it is known for its rare plant species. A total of 420 taxa was collected in this study, representing 418 species in 280 genera from 103 families. This includes 267 previously undocumented species for the park. Nine species are listed as either endangered, rare, of special concern, threatened, or watch-listed for North Carolina.

The oak mistletoe (Phoradendron leucarpum, Viscaceae) is well-documented to exhibit preference for a few potential host species in a given locality, even when many potential host species are present. In trying to explain this distribution, we examined the mechanisms by which mistletoe seedlings recognize potentially suitable hosts in the Piney Woods ecoregion of east Texas. An initial survey of patterns of infection on the campus of Sam Houston State University revealed that water oak (Quercus nigra) was host to nearly half of the mistletoes observed, despite comprising less than 15% of trees surveyed. Field experiments demonstrated that light, host physiochemistry, and volatiles released from potential host trees serve as cues affecting the viability and establishment of mistletoe seedlings. These results provoked further study in controlled laboratory settings, in which it was demonstrated that chemical compounds in the bark of local host trees (compared to trees that serve as hosts elsewhere, but not in our survey) induce significantly although slightly greater seedling viability. Establishment of haustoria depended only on the presence of these chemicals, regardless of host species. Importantly, we demonstrated that three common monoterpenes, limonene, β-myrcene, and β-phellandrene induce a positive growth response of mistletoe radicles. These results taken together suggest a model to explain local host preference in P. leucarpum, in which covariation between mistletoe fruit maturity and monoterpene production by hosts determines the distribution of successful haustorial establishment.

The unique morphology of quillworts has received limited attention, and such studies have been limited to only a few species. Our extensive field work during the past two decades has revealed variation in the structures of the plant, including the rhizomorph, scales, phyllopodia, and abscission caps. Polarity of the axes of southeastern quillwort rhizomorphs varies from discoid (most species), to elongate, to upright with axis branching in several species. In species of intermittent streams, these branched rhizomorphs produce plantlets that break off in running water. Scales are tiny brown or black structures in alternating whorls with sporophylls (leaves). They are often overlooked and easily removed when rinsing specimens. Found in most southeastern terrestrial/amphibious species, scales are absent from aquatic species. Scales are distinct from phyllopodia, the sclerified bases of sporophylls, but intermediates between scales and phyllopodia occur. Not all species with scales have phyllopodia. Although scales cannot be used for determination of species, their presence or absence is of taxonomic value. Research on southeastern Isoetes phylogeny could help determine which of the rhizomorph and scale characters are plesiomorphic.

Stable isotopic analysis of water use patterns in wetland vegetation can provide insight into the anticipated ecophysiological response of individual species to seasonal and/or episodic changes in water quality such as saltwater incursion into freshwater wetland ecosystems. In this study, variation in water source utilization over the course of a growing season was investigated in Taxodium distichum (baldcypress), a foundational species in both naturally occurring wetlands and regional wetland restoration projects in the southeastern United States. Over the course of the 2014 growing season, water use patterns were monitored in three baldcypress stands at the Timberlake Observatory for Wetland Restoration (TOWeR) in Tyrrell County, North Carolina, by comparing the isotopic composition (δ²H and δ¹⁸O) of xylem water extracted from plant tissue to that of the available water sources: surface water, sediment porewater, groundwater sampled from multiple locations in the region, and rainwater. Results indicate that water sources that are impacted by periodic saltwater incursion may be utilized by baldcypress at TOWeR, but the short-term health and reproductive competency of baldcypress at the site has not been negatively impacted by seasonal, episodic, surface water salinity incursions at the site.

Four sites of the Harpeth River, two upstream and two downstream of the Franklin Wastewater Treatment Facility in Franklin, Tennessee, were sampled to assess the impact of nutrient enrichment on the integrity of photoautotrophic periphyton. Concentrations of total phosphorus of water samples ranged from 310 μg^.L⁻¹ at the uppermost site to 1035 μg^.L⁻¹ at the site immediately downstream of the wastewater treatment facility. Concentrations of total nitrogen of water samples ranged from 687 μg^.L⁻¹ at the uppermost site to 1,434 μg^.L⁻¹ at the site immediately downstream of the wastewater treatment facility. Concentrations of benthic chlorophyll a did not differ significantly among the sites and ranged from 103 ± 11 mg^.m⁻² at the site immediately upstream of the wastewater treatment facility to 151 ± 13 mg^.m⁻² at the site immediately downstream. Percent composition of 186 algae taxa were documented: 92 taxa of soft-bodied algae and 94 taxa of diatoms. Values for the algae trophic index for soft-bodied algal assemblages increased from 71 at the site immediately upstream of the wastewater treatment facility to 107 at the site immediately downstream. Values for the pollution tolerance index for diatom assemblages decreased from 2.55 at the site immediately upstream of the wastewater treatment facility to 2.20 at the site immediately downstream. These index values demonstrate that the assemblages of soft-bodied algae and diatoms immediately downstream the wastewater treatment facility had a greater relative abundance of taxa tolerant of eutrophic conditions compared to the assemblages at the site immediately upstream.

The Freedom Hills Forever Wild Tract (FHFWT) is a 13,800 ha property acquired through multiple purchases by Alabama's Forever Wild Land Trust beginning in 2001. The FHFWT is managed by the Alabama Department of Conservation and Natural Resources for habitat conservation, as a wildlife management area, and for outdoor education. An intensive floristic study of this area was conducted from March 2012 through February 2017. A total of 761 taxa (757 species) from 431 genera and 136 families were collected, with 328 taxa representing county records. A total of 104 nonnative taxa were collected during the surveys. Forty-three percent of the total collections were county records and 72 exotic taxa collected during this survey were determined to be county records. Plant collections were deposited at the Alabama Natural Heritage Section Herbarium (ALNHS) with duplicates distributed to Anniston Museum of Natural History (AMAL), Auburn University Herbarium (AUA), Jacksonville State University Herbarium (JSU), and the University of West Alabama Herbarium (UWAL).

The netted pawpaw (Annonaceae, Asimina reticulata) is a widespread Florida endemic plant that produces relatively few fruits. To understand its distribution and reproductive success, we posed three questions: (a) how do time-since-fire (TSF) and pollinator visitation influence reproductive success, (b) is it pollinator dependent, and (c) does outcrossing increase reproductive success? In 2016, we studied 157 plants in three flatwoods burn units (last burned, 2015, 2012, or 2001) and one grazed pasture at Archbold Biological Station in south-central Florida. Plants in pasture and recently burned flatwoods exhibited greater flower, fruit, and seed output, suggesting that habitat openness may promote competitive release or increased pollinator visitation. Pollinator visitation was greatest on plants within the 1-yr TSF, and the hairy flower scarab (Trichiotinus viridans) was the most prevalent visitor across all sites. Autogamously crossed flowers produced no fruit, confirming that seed production is pollinator dependent. Although fruit retention (10.0%) and seed germination (27.8%) were low after geitonogamous crossing, close and far outcrossing increased retention (30.8% and 39.6%) and germination success (41.6% and 46.4%). This research suggests that A. reticulata reaches its maximum reproductive potential in open areas after outcrossing events, and that low fruit set may be due to the lack of an effective pollinator, resulting in inbreeding depression. Additionally, an investigation into raccoons (Procyon lotor) as fruit consumers and potential seed dispersers suggests that seeds may benefit from gut scarification.