Buried Viable Seeds in a North American Tall-Grass Prairie: The Resemblance of Their Abundance and Composition to Dispersing Seeds

The soil bank of buried viable seeds in October 1978 at Tucker Prairie in Missouri, USA, was assessed from 30 sod plugs (5.8 cm diam., 12.0 cm deep) spread in greenhouse trays for 145 d. 17.1 ? 8.7 (x ? s) seedlings per plug emerged, equivalent to 6470 seeds m-2, a figure higher than previous reports for prairies. Most (74%) seedlings emerged during the first month. Seventy-nine per cent of the seedlings survived to be identified to 28 species, 18 of which were dicotyledons, and 10, monocotyledons. Juncus tennis comprised 59% of the individuals. Forty-six per cent of the species produced 1 or 2 individuals. The density of seeds in the soil shows a 71% reduction from the density of seeds in the seed rain. The majority of common species in the seed rain (7 of 10) appear in the soil bank. In contrast, many of the common elements of the bank (7 of 11) are not detected in the rain. These latter species probably have long-lived seeds with pulsed input, and the former species have more transient presence in the soil. Thus, the seed rain resembles the soil bank more than the bank resembles the rain.