Belowground annual ring growth coordinates with aboveground phenology and timing of carbon storage in two tallgrass prairie forb species.

Premise Of The Study: Herb chronology, the study of belowground annual growth rings in perennial forbs, has much potential as a tool for monitoring plant growth as a function of environment. To harness this potential, understanding of the coordination between ring ontogeny, aboveground phenology, and the temporal allocation of carbon products belowground in herbaceous forbs must be improved.

Methods: We investigated these relationships in two southern United States tallgrass prairie perennial forb species, Asclepias viridis and Lespedeza stuevei, making monthly excavations for a year.

Latitudinal trends in genus richness of vascular plants in the Eocene and Oligocene of North America.

The latitudinal richness gradient is a frequent topic of study on the modern landscape, but its history in deep time is much less well known. Here, we preliminarily evaluated the paleolatitudinal richness gradient of vascular plants for the Eocene (56-33.9 million years ago) and Oligocene (33.

Bioaccessibility and speciation of arsenic in country foods from contaminated sites in Canada.

Arsenic in foods obtained through foraging or hunting (country foods) in contaminated areas has not been reported; moreover the chemical form (arsenic speciation) is not known. Bioaccessibility extractions can be used to extract the arsenic from samples, giving information about the arsenic that is available for absorption into humans. Bioaccessibility of arsenic was measured in country foods (berries, other plants, mushrooms and hares) collected from contaminated sites in Canada.