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Potassium deficiency is the most common nutrient deficiency on landscape palms in the southeastern United States. Early symptoms appear as translucent yelloworange and/or necrotic spotting on the oldest leaves (Broschat 1990). As the deficiency progresses, leaflet tip necrosis and frizzling develop, which eventually results in premature loss of the leaf (Fig. 1). Deficiency symptoms are most severe on the oldest leaves because potassium is mobile within the palm (Mengel & Kirkby 1982). Under conditions of deficiency, the palm is able to extract potassium from the oldest leaves and translocate it to the newly developing leaves, allowing growth to continue in the absence of sufficient potassium in the soil. Depending on the species and potassium deficiency severity, leaf death occurs from one to three months after necrosis is first observed on a particular leaf. In contrast, natural senescence of healthy, non-potassium-deficient older leaves occurs rapidly, with the oldest leaf being completely green one day, uniformly orange-brown the next day, and completely necrotic by the third or fourth day. [ABSTRACT FROM AUTHOR]

Sabal palmetto (cabbage palm) is a native palm species used commonly in urban landscaping throughout Florida. In addition to its aesthetic appeal and high tolerance to the variable environmental conditions found in Florida, the use of cabbage palms in landscaping should be expected to promote urban wildlife because the tree provides food and nesting sites for various organisms, including arthropods. In this study, we compared arthropod number, abundance, and biodiversity in cabbage palms between natural and landscaped environments. Trees in natural environments supported more individuals and greater species richness than trees in landscaped environments. Environmental factors, such as human activity and depauperte botanical communities, might explain why landscaped cabbage palms supported fewer arthropods. This suggests that landscaping with isolated native trees, such as the cabbage palms in this study, in an otherwise lawn-manicured environment might have adverse effects on biodiversity as predicted by island biogeography. Natural and landscaped palms supported a similar diversity of transient arthropods, which were primarily involved either directly or indirectly with pollination. Transient arthropods were found flying around cabbage palms, which might explain the ability of the arthropods to use landscaped trees. Increased use of native species such as S. palmetto in urban landscapes should have a positive effect on urban wildlife that can disperse broadly, such as flying arthropods and birds. [ABSTRACT FROM AUTHOR]

Abstract: The efficient utilization of biomass as a renewable fuel relies on the identification of readily available fuel sources and an adequate description of their decomposition reactions. Cabbage palm (Sabal palmetto) is one potential local energy source for the Southeastern United States. The kinetics of pyrolysis of three particle size fractions (125–250, 250–300, 300–500μm) of cabbage palm leaf, stalk and trunk were examined using nonisothermal thermogravimetric analysis with heating rates of 25, 50 and 100°Cmin−1 under constant nitrogen flow. Using the Arrhenius equation to calculate the activation energy and pre-exponential factor, three distinct fractions, corresponding primarily to hemicellulose, cellulose and lignin, were found to decompose over three temperature ranges, each with distinct activation energies. The largest mass loss occurred in the mid-temperature fraction (40–45%); the low temperature region had approximately 30% mass loss and the high temperature region had 15–25% mass loss. Pyrolysis at higher heating rates decreased the activation energy of each palm material, whereas particle size was not correlated with activation energy. For leaf, stalk and trunk, activation energies ranged from 64 to 115, 67 to 152 and 19 to 25kJmol−1 for the low, medium, and high temperature range fractions, corresponding to hemicellulose, cellulose and lignin, respectively. [Copyright &y& Elsevier]

We examined seasonal diets of an introduced population of Dama dama dama (European Fallow Deer) on Little St. Simons Island, GA. We analyzed rumen contents from hunter-harvested deer during fall and winter of 2004-05 and 2005-06. Fecal pellets also were collected monthly from November 2004 to December 2005 and examined microscopically for unique plant-cell characteristics. Fallow Deer utilized a variety of food items based on seasonal availability, although mast and browse were the most abundant food items in the rumens examined. Fallow Deer preferred Quercus spp. (oak) acorns, but consumed more Sabal palmetto (Cabbage Palm) fruit when acorns were less abundant. Microhistological techniques underestimated the occurrence of highly digestible items such as mast, but were more effective at identifying grasses and browse. Grasses were the most common and abundant forage class in feces, with peak grass use in the summer (67%). Fallow Deer's ability to utilize a wide variety of food items including low-quality forage has contributed to their success in this barrier island ecosystem. However, low productivity, suppressed body weights, and small antler characteristics are likely due to a low-quality diet and over-population. [ABSTRACT FROM AUTHOR]

Abstract: The feed back experience of using straight vegetable oil (SVO) as a fuel in the existing diesel engines evidences the need for fitting several physical properties, among them the fuel viscosity. An empirical modelling is proposed in order to interpolate viscosity to any kind of diesel oil/SVO blend. This model is fitted on an experimental viscosity database on blends, varying the SVO mass proportion in the blend, the blend temperature between cloud point and 353K, and including six vegetable oils varying the fatty acids composition. Extrusion rheology was also checked by varying the pressure drop. Measurements show that blends behave Newtonian. [Copyright &y& Elsevier]

Sea-level rise threatens low-lying coastal ecosystems globally. In Florida, USA, salinity stress due to increased tidal flooding contributes to the dramatic and well documented decline of species-rich coastal forest areas along the Gulf of Mexico. Here, we present the results of a study of coastal forest stand dynamics in thirteen 400 m2 plots representing an elevation gradient of 0.58–1.1 m affected by tidal flooding and rising sea levels. We extended previously published data from 1992–2000 to 2005 to quantify the full magnitude of the 1998–2002 La Niña-associated drought. Populations of the dominant tree species, Sabal palmetto (cabbage palm), declined more rapidly during 2000–2005 than predicted from linear regressions based on the 1992–2000 data. Dramatic increases in Juniperus virginiana (Southern red cedar) and S. palmetto mortality during 2000–2005 as compared with 1995–2000 are apparently due to the combined effects of a major drought and ongoing sea-level rise. Additionally, coastal forest stands continued to decline in species richness with increased tidal flooding frequency and decreasing elevation. Stable isotope (H, O) analyses demonstrate that J. virginiana accesses fresher water sources more than S. palmetto. Carbon isotopes reveal increasing δ13C enrichment of S. palmetto and J. virginiana with increased tidal flooding and decreased elevation, demonstrating increasing water stress in both species. Coastal forests with frequent tidal flooding are unable to support species-rich forests or support regeneration of the most salt-tolerant tree species over time. Given that rates of sea-level rise are predicted to increase and periodic droughts are expected to intensify in the future due to global climate change, coastal forest communities are in jeopardy if their inland retreat is restricted. [ABSTRACT FROM AUTHOR]

The sabal palmetto woodland is a tropical plant formation dominated by Sabal mexicana, with restricted distribution to southeast Mexico. Sabal palms grow on poor soils but accumulate large quantities of organic substrate in their crowns, harboring a contingent of plants that use it as phorophyte. Although it is a threatened formation, basic information on its biodiversity is scant. We examined the floristic diversity of recruited (diameter at breast height, DBH, ≥1 cm) and understory (DBH ≤ 1 cm) plants, and its variation with anthropogenic disturbance. We also examined the floristic diversity of plants that use the sabal palms as phorophytes, and assessed its variation with human impact. All plants present in transects within a conserved and an adjacent perturbed area were sampled. The list of observed taxa shows that this vegetation has a clear affinity with tropical dry and wet forests of Mexico, with a small representation of taxa from desert ecosystems. The floristic contingent included a total of 81 species in 2000 m². Richness, composition and diversity were affected by disturbance. Recruited and understory vegetation in the disturbed site were 5- and 1.6-times less diverse than in the conserved site, and species of mature, conserved vegetation were substituted by heliophytes in the disturbed site. In contrast, abundance of palms and diversity and identity of epiphytic/hemiepiphytic plants were not affected by disturbance. We show that even monodominated tropical ecosystems growing on poor soils have a high floristic diversity and that current anthropogenic impact threatens not only species and populations but also entire plant formations. [ABSTRACT FROM AUTHOR]

Habitat preferences for many woodpeckers are poorly known in many regions of North America. Seven woodpecker species use forested wetlands in peninsular Florida, yet no study has examined habitat use by woodpeckers in these forests. From September 1991 to August 1992, we used unlimited-distance point counts to sample birds at 32 stations in 2 forested wetland types (spring-fed and blackwater) in central Florida. We documented 1415 visual or aural woodpecker detections. Melanerpes carolinus (Red-bellied Woodpecker), Picoides pubescens (Downy Woodpecker), and Dyrocopua pileatus (Pileated Woodpecker) were common, accounting for 91% of all detections. Overall woodpecker abundance was greater in spring fed forests than in blackwater forests. The relative abundance of 4 species was greatest during the fall and winter; this trend likely reflected shifts between habitats in response to fruit production as well as an influx of migrant Sphyrapicus varius (Yellow-bellied Sapsuckers). The relative abundance of Red-bellied and Pileated woodpeckers was greatest at sites surrounded by extensive forest cover. Unlike other studies, we found no relationship between woodpecker abundance and tree or snag basal area. The presence of Quercus spp. (oaks) also did not appear important to woodpeckers. Compared to other studies, snag density in the forests we sampled was high. This may have reduced the importance of snags to woodpeckers or made detecting relationships difficult. A high density of Sabal palmetto (sabal palm) may have provided additional foraging and nesting/roosting sites that further contributed to the lack of correlations between woodpecker detections and the presence of snags and oaks. [ABSTRACT FROM AUTHOR]

Abstract: Gould’s petrel (Pterodroma leucoptera leucoptera) was restricted, essentially, to a single breeding locality – Cabbage Tree Island, Australia. As a safeguard against extinction, an additional breeding colony was established on nearby Boondelbah Island, where artificial nesting habitat was created by installing 100 plastic nest boxes. Over two years, a total of 200 nestling Gould’s petrels were translocated from Cabbage Tree Island to these boxes. Colonies on both islands were then monitored for a further four years. Selection of nestlings for transfer was based on prior knowledge of growth, plumage development and emergence from the burrow, and aimed to select only birds that were 11–28 days from fledging (DBF) in 1999 and 11–22 DBF in 2000. Of the first 100 nestlings translocated to Boondelbah Island (in March 1999), 95 fledged successfully 8–27 days after transfer (mean=17.3 days). Of the second 100 nestlings translocated (in March 2000) all successfully fledged 9–22 days after transfer (mean=15.1 days). The removal of young had no discernible effect on the subsequent breeding productivity of the donor pairs. In all, 41 Gould’s petrels have been recorded at the new colony on Boondelbah Island, where at least 27 nest boxes have been visited. Ten translocated fledglings (nine male, one female) have returned to the translocation site, taking up nest boxes that were, on average, 5.5m from the box from which they fledged. An additional 27 non-translocated birds, of unknown origin, have also nested in nest boxes on Boondelbah, along with four birds previously known from Cabbage Tree Island. Two nestlings transferred to Boondelbah Island have returned to Cabbage Tree Island. Within five years of the first translocation, the newly established colony on Boondelbah Island has produced a total of 24 eggs and 14 fledglings. The translocation technique developed for Gould’s petrel has broad applicability, being readily adaptable for other burrow-nesting seabirds. [Copyright &y& Elsevier]

The contribution of stem water storage to the water balance of the arborescent palm, Sabal palmetto, was investigated using greenhouse studies, field measurements and a tree-cutting experiment. Water balance studies of greenhouse trees (1.5 to 3m tall) were conducted in which transpiration was measured by weight loss, and changes in soil and stem water content by time-domain reflectometry. When the greenhouse plants were well-watered (soil moisture near saturation), water was withdrawn from the stern during periods of high transpiration and then replenished during the night so that the net transpirational water loss came primarily from the soil. As water was withheld, however, an increasing percentage of daily net transpirational water loss came from water stored in the stem. However, studies on palms growing in their natural environment indicated that during periods of high transpiration leaf water status was somewhat uncoupled from stem water stores. In a tree-cutting experiment, the maintenance of high relative water content of attached leaves was significantly correlated with stern volume/leaf area. Leaves of a 3-m tree remained green and fully hydrated for approximately 100d after it had been cut down, whereas those of a 1-m-tall plant turned brown within one week. The significance of stem water storage may be in buffering stem xylem potentials during periods of high transpiration and in contributing to leaf survival during extended period of low soil water availability. [ABSTRACT FROM AUTHOR]

The functional importance of water storage in the arborescent palm, Sabal palmetto, was investigated by observing aboveground water content, pressure-volume curve parameters of leaf and stem tissue and leaf epidermal conductance rates. The ratio of the amount of water stored within the stem to the leaf area (kg m-2) increased linearly with plant height. Pressure- volume curves for leaf and stem parenchyma differed markedly; leaves lost turgor at 0.90 relative water content and -3.81 MPa, while the turgor toss point for stem parenchyma occurred at 0.64 relative water content and -0.96MPa. Specific capacitance (change in relative water content per change in tissue water potential) of stem parenchyma tissue was 84 times higher than that of leaves, while the bulk modulus of elasticity was 346 times lower. Leaf epidermal conductance rates were extremely low (0.32-0.56 mmol m-2 s-1) suggesting that S. palmetto are able to strongly restrict foliar water loss rates. Structurally, stems of S. palmetto appear to be well suited to act as a water storage reservoir, and coupled with the ability to restrict water loss from leaf surfaces, may play an important role in tree survival during periods of low water availability. [ABSTRACT FROM AUTHOR]

The article presents an image of Cabbage palm at the westernmost edge of its natural range in the Florida Panhandle.

Presents information on palm Lisa, a cultivar of Sabal palmetto found in Florida. Use of Sabal palmetto in landscaping; Characteristics of the palm; Description of its leaves.

The article discusses research being done on saw palmetto extract for benign prostatic hyperplasia. Saw palmetto preparations are known to be safe and very well tolerated, producing few adverse effects. However, the authors conclude that saw palmetto was not superior to placebo for improving urinary symptoms and objective measures of the disease.