Managing Weeds in Potato Rotations Without Herbicides

Abstract

Managing weeds without herbicides requires an integration of methods and strategies and a change in how weeds are perceived. Weeds should be managed in a holistic, intentional and proactive manner. Understanding the interactions between the cropping system and the weed community and managing the cropping system to prevent and discourage weeds and maintain a low weed seedbank is necessary for successful weed management in organic systems. Cultural practices, including a well-planned crop rotation, planting cover crops, sanitation practices, and optimum row spacing and timing of planting are important aspects of managing weeds in organic systems. Multiple, well timed shallow cultivations or flaming can eliminate many early season weeds. Once emerged, many crops are fast growing and produce a canopy able to suppress weeds. New technologies for detecting crop rows and weeds coupled with precision cultivation, flaming, and application of nonselective organic herbicides are being developed and hold promise to reduce the need for hand weeding.Resumen El manejo de malezas sin herbicidas requiere una integración de métodos y estrategias y un cambio en la manera como se perciben las malezas. Éstas deben manejarse de una manera holística, intencional y proactiva. Es necesario un entendimiento de las interacciones entre el sistema de cultivo y la comunidad de malezas y del manejo del sistema de cultivo, para prevenir y dificultar a la maleza y mantener un bajo banco de semillas harvenses para un manejo exitoso de las malezas en sistemas orgánicos. Las prácticas culturales, incluyendo una rotación de cultivos bien planeada, plantando cultivos de cobertura, prácticas sanitarias, y un óptimo espaciamiento entre surcos y fechas de siembra, son aspectos importantes para el manejo de malezas en sistemas orgánicos. Escardas múltiples, superficiales y bien programadas, o flameo, pueden eliminar muchas malezas tempranas. Una vez emergidos, muchos cultivos son de rápido crecimiento y producen un follaje capaz de suprimir a las malezas. Se han estado desarrollando nuevas tecnologías para detectar los surcos del cultivo y las hierbas juntas con cultivos de precisión, flameo, y la aplicación de herbicidas orgánicos no selectivos, y son prometedoras para reducir la necesidad de deshierbes manuales.

Evaluating Mustard Seed Meal for Weed Suppression in Potato (Solanum tuberosum)

“…More U.S. potato hectares (75%) are treated with the herbicide metribuzin than any other pesticide and 91% of potato hectares receive an herbicide (Guenthner, Wiese, Pavlista, Sieczka, & Wyman, 1999;USDA-NASS, 2014). Weed management in organically grown potatoes typically consists of a combination of an early cultivation that removes the top of the hill formed at planting (drag off), a cultivation to reform the hill (rehilling) that uproots and buries early emerging weed seedlings prior to potato emergence, additional shallow cultivations if needed, and reservoir tillage (dammer-diking) that creates shallow pockets in the furrows to improve water infiltration and prevent runoff (Boydston & Vaughn, 2002;Boydston, 2010). Once the potato canopy is near row closure, later emerging weeds are largely suppressed by the dense potato canopy.…”

“…Potatoes generally take 3 to 5 weeks to emerge depending on planting depth, soil temperatures, and seed condition. This allows for early cultivation and rehilling operations that control early weed flushes (Boydston & Vaughn, 2002;Boydston, 2010). A harrow or rod weeder operation that removes the top of the potato hill and leaves a flat topped hill (termed "drag off") is often practiced when potato shoots have sprouted, but still not emerged.…”

Yield and competitive ability in potato cultivars characterised by different developmental timing

“…To date, 11 cases of herbicide‐resistant weeds have been reported in potato crops, eight resistant to photosystem II inhibitors and three to ACCase inhibitors (Heap, ). The threat of herbicide‐resistant weeds, together with the increased consumer demand for pesticide‐free food, has led to a major increase in non‐chemical and organic production (Boydston, ). Organic potato production is still below 4% of both total organic production and total potato production (Pawelzik & Möller, ).…”

The Role of Weed and Cover Crops on Soil and Water Conservation in a Tropical Region

“…A key to effectiveness weed management is a holistic approach regarding the scenario considered and must include a combination of tactics and practices in order to successfully and economically reduce the potentially negative impacts inherent to weeds incidence [2]. There are numerous methods of mechanical control of weeds including mowing, cultivation, hoeing, flaming, mulching, and hand weeding.…”