Root characterization of three forage species grown in southwestern Uruguay

Abstract

Forage crops are widely grown in the mixed cropping system of southwestern Uruguay. There is renewed interest in the use of forages for soil improvement and carbon sequestration, but the root growth of forages has received little study. Field observations were made of the root systems of tall fescue (Festuca arundinacea Schreb.), alfalfa (Medicago sativa L.) and chicory (Cichorium intybus L.). Soil core samples were used to measure root count and biomass distributions to a depth of 1 m. Roots were detected to a depth of 1 m for all species, although half of the root biomass for each species was located in the top 20 cm of the soil. The distribution of root counts differed with the greatest number of root axes found above a depth of 20 cm for tall fescue and chicory, and below 20 cm for alfalfa. Key words: Carbon sequestration, perennial forages, subsoil, grasslands