A survey of 27 herbaceous and woody plant taxa was conducted to identify possible alternative hosts of the xylem-limited bacterium, Xylellafastidiosa. Samples were collected from wild and cultivated plants inhabiting and surrounding the National Park Service Daingerfield Island Nursery in Alexandria, Virginia, and from national parks in Washington, D.C. These samples were analyzed using up to 3...

A rapid and efficient protocol was developed for inducing indirect organogenesis using leaf explants of Vitex negundo L. Explants were cultured on MS with different concentrations of 2,4-D and IAA in combination with BAP for callus induction. The frequency of callus induction increased with increasing concentration of IAA (0.3 mg/l) and BAP (0.3 mg/l) at optimal level. The shoot buds appeared e...

To assess the influence of stream water on leaf gas exchange and water potential in different sized boxelder trees (Acer negundo L.), we compared these characteristics in trees growing beside a perennial stream and a nearby ephemeral stream in a montane-riparian forest in northern Arizona. Patterns of tree water use were quantified by stable isotope analysis (delta(18)O). Physiological characte...