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Most genetically based features should be available for use in cladistic analysis. Palynologists routinely measure polar (P) and equatorial (E) axes and place pollen into size classes defined by earlier pollen workers. Grouping of pollen into globally arbitrary classes may not correspond to statistically significant differences among the taxa of a study. We propose a model using conventional statistical procedures coupled with data visualization and Monte Carlo simulation. This approach is not a final solution to the general problem of coding continuous characters into discrete states; it is an attempt to address the problems of character state delimitation in pollen morphology. We suggest that the coding of continuous measurement variables (e.g., P, E) into character states should be done following a logical sequence of interactive visualization (2D and 3D) of bivariate frequency distributions including the inspection of prediction and confidence ellipses (e.g., 99%), and use of ANOVA. We illustrate our approach using realistic pollen data sets generated by a computer program (POLSIM) written to perform Monte Carlo sampling from normally distributed statistical populations of polar and equatorial axes. Our model is then applied to an original data set of 4,134 pollen grains from the Ebenaceae, resulting in the coding of the four genera into three character states for pollen size.

The vascular flora of Jamaica Bay Wildlife Refuge, comprising 3,705 hectares, is part of Gateway National Recreation Area, New York, New Jersey. A significant aspects of the refuge's history is [...]

The article presents a study which investigates nonnative invasive woody vascular plant species at Jamaica Bay Wildlife Refuge (JBWR) in Long Island, New York and determines which of them are most aggressive and problematic. It reveals several alien species including tree of heaven, oriental bittersweet, multiflora rose, and porcelain berry. It states that the tree of heaven, oriental bittersweet, and porcelain berry are the most aggressive species.

The article discusses a study that sampled the arborescent vegetation located at three sites within Inwood Park in Manhattan, New York, by the quadrant method in October 2004 and May 2005. The vegetation was compared with the trees present in the same quadrants on a map of trees at Inwood Park, prepared by the federal Works Program Administration in 1935. It cites the dominant trees at each site in 1935 and 2005, as well as the increased mean tree diameter over the past 70 years.

(1) The demographic behaviour of two Viola species (V. fimbriatula and V. lanceolata) from open clearings is reported and compared with that of three woodland species. (2) Measurements were made of the size of the seedbank in the soil, germination, number and growth of seedlings numbers of pre-reproductive and reproductive ramets, and fecundity over five years. Seedling growth seed weight and number leaf production and grazing losses and investment in reproductive structures were also studied. (3) Seed banks of the clearing species were larger by a factor of five than those of the forest species. All showed plasticity in many characteristics but the clearing species produced more seeds per plant and lighter seeds. Clearing species grew faster than forest species. Irrespective of habitat, rhizomatous species produced more seed than stoloniferous species. (4) Conclusions are drawn from the entire series of papers Viola populations appear to be demographically unstable. [ABSTRACT FROM AUTHOR]

Studies the population biology of the Genus viola. Mechanism of adaptation of three species of violet, Viola sororia, V. blanda and V. pallens; Size of the soil seed bank of V. blanda and V. pallens; Calculation of the violets' population flux, age distribution, survival, and life expectancy.