Crops

Assessing effects of an alfalfa cover crop on biological control and tree nutrition in organic pear orchards

Organic pear growers must balance the conflicting pressures between nitrogen levels and densities of pear psylla, a nitrogen-loving pest of pears. We are assessing in 3 certified organic orchards and 1 experimental orchard whether planting of alfalfa leads to improved tree nutrition and biological control of psylla. Alfalfa was planted in 2 ft wide strips […]

Growing nitrogen in the organic orchard

Two on-farm trials were established in 2008 to test different approaches to growing nitrogen within an orchard. The trial at Warren Morgan Orchard (WMO) compared four perennial legume species (ladino white clover, alfalfa, birdsfoot trefoil, kura clover) direct seeded into the existing alley vegetation with or without suppression. All species were successfully established, with better […]

Evaluation of seed treatments for organic vegetable production in the Pacific Northwest

This study addresses management of damping-off in organic vegetables in central Washington, using pea as an early season, model crop. The disease is being examined under low soil temperature and high soil moisture conditions of early spring in the Columbia Basin, when damping-off is most severe. PhD student, Ana Vida Alcala, spent 2009 and spring […]