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Question: To what extent do bison serve as seed dispersers via epizoochory and endozoochory in tallgrass prairie, and does this differ by age-sex class of bison and by month? Location: Tallgrass Prairie Preserve, Osage County, Oklahoma, USA. Methods: We collected bison hair from 19 bulls, 45 cows, and 47 juveniles in fall and we collected bison dung monthly for a year. We recovered and identified seeds from hair and dung samples, and classified seeds by size and diaspore characteristics. Results: Bison hair samples contained 2768 seeds from at least 76 plant species. Several species found in hair did not feature specialized appendages for adhesive dispersal. Seed species composition differed in hair collected from bulls, cows and juveniles, possibly due to differential habitat use. Dung samples contained 7418 seeds from at least 70 species, from which graminoids accounted for 3936 seeds from 27 species. Species composition of seeds contained in dung samples differed among months, corresponding to availability. Grasses constituted about half the seeds in both dung and hair samples, but Asleraceae were more strongly represented in hair, while Scrophulariaceae and Solanaceae were more strongly represented in dung. Conclusions: We conclude that bison are potentially important dispersers of forbs as well as graminoids. A high abundance and wide diversity of seeds were found in both bison hair and dung. The great majority of seeds found undamaged in bison dung were small seeds, which agrees with the `foliage is the fruit' hypothesis. Dispersal by both epizoochory and endozoochory may play an important role in life history of many species in tallgrass prairie landscapes. [ABSTRACT FROM AUTHOR]

The biodiversity crisis demands that scientists be careful in their application of quantitative methods, because misuse of biodiversity statistics can lead to trivial but real patterns (artifacts) or to false patterns (artifictions). While misuses such as biases in taxonomic ratios, standardization by dividing by area or individuals, and the rarefaction effect have been repeatedly recognized in the literature, they continue to appear regularly in the scientific literature. Here, we illustrate (using data from North American floras and the Tallgrass Prairie Preserve in Oklahoma, USA) examples of how artifacts and artifictions can lead to misinterpretation of biodiversity patterns. We urge biogeographers and ecologists to be vigilant when using biodiversity statistics, to avoid false interpretations. [ABSTRACT FROM AUTHOR]

The 15,410 ha Tallgrass Prairie Preserve (Osage County, Oklahoma), managed by The Nature Conservancy, consists of a variety of grassland, forested, wetland, and disturbed habitats. 1,612 specimens of vascular plants collected between 1992 and 2007 were examined to obtain a vouchered flora of the preserve. The known flora consists of 763 species in 411 genera and 109 families. 12.1% of the species are not native to North America. [ABSTRACT FROM AUTHOR]

Abstract: Although the relationship between soil reaction and species richness is of great theoretical interest, and has been relatively well studied in temperate latitudes, the southern Great Plains of North America have not received much attention. We analyzed the relationship between species richness and measures of soil reaction (pH, cation exchange capacity, Ca) in 418 10 m x 10 m samples (with nested smaller quadrats) in the Tallgrass Prairie Preserve, Osage County, Oklahoma. We found a negative correlation of richness with soil reaction that is consistent across scales and years in grasslands, with soil calcium exhibiting the strongest relationships. The relationship in woodlands is weakly positive. The proportion of (primarily Eurasian) exotic species is positively related to calcium concentrations in both woodlands and grasslands. Although our results are not inconsistent with species pool hypotheses, critical tests of such hypotheses are operationally difficult. [ABSTRACT FROM AUTHOR]

Abstract: Viruses are most frequently discovered because they cause disease. To expand knowledge of plant-associated viruses beyond these narrow constraints, non-cultivated plants of the Tallgrass Prairie of the United States were systematically surveyed for evidence of viruses. This report discusses putative viruses of the family Secoviridae identified by the survey. Sequence analysis suggests the presence of at least six viruses in the study site, including Bean pod mottle virus, Maize chlorotic dwarf virus, three previously undescribed viruses within the subfamily Comovirinae and one unclassifiable virus. [Copyright &y& Elsevier]

Abstract: The diversity of viruses associated with non-cultivated plants was assessed from plant samples collected in the Tallgrass Prairie Preserve of northeastern Oklahoma, USA. The samples were processed to determine the sequences of nucleic acids extracted from the virus-like particle fraction of plant homogenates. Sequences from 95 specimens of 52 plant species included those of probable origin from the genomes of plants (including retroelements), bacteria, fungi, other organisms, and viruses. Virus-like sequences were identified in sequences from 25% of the specimens, coming from 19% of the plant species. Evidence of a member of the genus Tymovirus was found in 16 specimens of 6 plant species, making it the most predominant virus associated with the sampled plants. There was evidence of the presence of more than one virus in each of six specimens. [Copyright &y& Elsevier]