Emergence and seedling survival of Lotus tenuis in Festuca arundinacea pastures.

Abstract

Emergence and survival of seedlings of lotus or narrowleaf trefoil (Lotus tenuis Waldst.) were monitored in 4 grazed pastures dominated by tall fescue (Festuca arundinacea Schreb.) for 2 successive years. The objective was to detect patterns and environmental conditions promoting successful seedling establishment of lotus. Emergence followed a seasonal pattern each year, with most emergence occurring towards the end of winter. Seedling emergence occurred mainly in heavily grazed sites which occupied 45 to 90% of each pasture. Seedling emergence was greatest, but seedling survival was poorest in the wettest year. Competition resulting from climatic conditions favoring growth of established pasture plants was detrimental to establishment of lotus seedlings. In contrast, heavily grazed areas provided microsites that enhanced survival of new recruits during the spring growing season. Dense seedling stands emerging on feces were overcrowded and suffered the highest mortality, thus, they contributed little to recruitment of lotus. However, dispersal of lotus was enhanced by the presence of seeds in livestock feces.