Reduction in below-ground biomass estimates from freezing of soil cores

Study was designed to quantify the effects of freezing soil cores prior to washing on estimates of below-ground biomass. Cores were extracted from nearly pure stands of 3 native grasses growing in a southern USA mixed-grass prairie. Estimates of crown + rhizome biomass in the top 10-cm of the soil profile did not differ as a function of pre-washing treatment (frozenvs unfrozen). However, estimates of root biomass were 26% less from frozen (434 g m^–2) than unfrozen samples (585 g m^–2).     

Theophrastus on geophytes

NEGBI, M., 1989. Theophrastus on geophytes . The nature of the geophilous organs of the geophytes described by Theophrastus (371-287 B.C.) in Historia Planiarum and De Causis Planlarum is presented and discussed. Most of the geophytes and the hydrogeophytes mentioned in these books (excluding species of Allium , biennial vegetables, and a few others) are critically reviewed. Certain lost agricultural practices mentioned by Theophrastus are strengthened and made explicable by comparisons from Pliny's Natural History , and Hebrew literature of the first centuries A.D.: Mishnah and Talmud. Theophrastus's interest in plants is shown to be of a pure nature although most of his examples are cultivated or otherwise useful plants. The possible sources of his knowledge of Egyptian plants are discussed.