Some Arkansas Ferns

Biometry of stomata in Blechnum species (Blechnaceae) with some taxonomic and ecological implications for the ferns.

Morphological stomatal traits, such as size, form and frequency, have been subject of much literature, including their relationships with environmental factors. However, little effort have focused on ferns, and very few in the genus Blechnum. Stomatal length, width and frequency (as stomatal index) of a number of specimens of fourteen Neotropical species of Blechnum were measured in adult pinna...

How early ferns became trees.

A new anatomically preserved fern, discovered from the basalmost Carboniferous of Australia, shows a unique combination of very primitive anatomical characters (solid centrarch cauline protostele) with the elaboration of an original model of the arborescent habit. This plant possessed a false trunk composed of a repetitive branching system of very small stems, which established it as the oldest...

Arkansas Swine Odor Survey

Swine Odor Survey Participants Arkansas Pork Producer’s Association National Pork Board University of Arkansas, Division of Agriculure, Cooperative Extension Service USDA, Natural Resource Conservation Service Arkansas Department of Environmental Quality Arkansas Natural Resources Commission University of Arkansas, Division of Agriculure, Animal Science Department Tyson Foods Inc. Swine Divisio...

Arkansas Agricultural Experiment Station

Maidenhair Ferns, Adiantum, are Indeed Monophyletic and Sister to Shoestring Ferns, Vittarioids (Pteridaceae)

Across the tree of life, molecular phylogenetic studies often reveal surprising relationships between taxa with radically different morphologies that have long obscured their close affiliations. A spectacular botanical example is Rafflesia, a holoparasite that produces the largest flowers in the world, but that evolved from tiny-flowered ancestors within the Euphorbiaceae. Outside of parasitic ...