Agronomic Cover Crop Management Supports Weed Suppression and Competition in California Orchards

• Published in: Weed science Vol. 70; no. 5; pp. 595 - 602
• Main Authors: Haring, Steven C., Hanson, Bradley D.
• Format: Journal Article
• Language: English
• Published: New York, USA The Weed Science Society of America 01-09-2022; Cambridge University Press
• Subjects: Agricultural ecosystems; Agricultural practices; Agroecology; Agronomic crops; almonds; Biodiversity; Competition; Cover crops; Crop management; Crop planting; Crop residues; Cropping systems; Crops; ecological weed management; Ecosystem services; Experiments; Flooring; Herbicides; integrated pest management; Irrigation; Juglans regia; Loam soils; Orchards; Phenology; Planting; Planting date; Plants (botany); Prunus dulcis; Seasons; Trees; Vegetation; walnuts; Weeds; Winter; United States > US; California; ecological weed management; walnuts; almonds; Agroecology; integrated pest management
• ISSN: 0043-1745; 1550-2759
• DOI: 10.1017/wsc.2022.48

Cover crops enhance the biodiversity of cropping systems and can support a variety of useful ecosystem services, including weed suppression. In California orchards, cover crops are typically implemented as annual plants that can replace resident vegetation in orchard alleyways during the rainy winter season. Our research objective was to evaluate cover crop management factors that support a competitive, weed-suppressing cover crop in the unique orchard systems of central California. We conducted two experiments: an experiment evaluating cover crop management intensification in walnuts (Juglans regia L.) and an experiment evaluating multispecies cover crop mixes and planting date in almonds [Prunus dulcis (Mill.) D.A. Webb]. These experiments demonstrate that timely cover crop planting is important for producing an abundant cover crop, and a variety of cover crop management programs can produce weed-suppressing cover crops. However, cover crops do not result in weed-free orchards and should be considered within the context of integrated management programs. The apparent flexibility of orchard cover crop management provides an opportunity to promote other agroecosystem services, with vegetation management and weed suppression as complementary management goals.