Project Overview
Annual Reports
Commodities
- Agronomic: potatoes
Practices
- Crop Production: cover crops, irrigation, no-till
- Pest Management: allelopathy, integrated pest management, physical control, weed ecology
- Production Systems: holistic management, organic agriculture
- Soil Management: green manures, organic matter, nutrient mineralization, soil quality/health
Abstract:
A research experiment was conducted near Oakes, North Dakota in 2009 and 2010, and repeated at Carrington, North Dakota, in 2010 and 2011 to evaluate the potential for weed control and potato yields using cover crops in irrigated potato production. Cover crop treatments included no cover crop, triticale, rye, hairy vetch, and rye/hairy vetch. The hairy vetch winter killed at Oakes and was replaced with turnip/radish and rye/canola cover crop treatments. Cover crop termination methods for both locations were disk-till, roto-till, and herbicide. The results were analyzed as a RCBD with a factorial arrangement and as a RCBD with a check. Locations were not combined due to winter-kill of hairy vetch in 2009-2010 and replacement with turnip/radish and canola. At Oakes compared to the no cover crop treatment cover crops treatments had 5% greater weed control 14 DAP, 14% greater 29 DAP, and 2% greater 51 DAP. At Carrington compared to the no cover crop treatment cover crops had 1% greater weed control 13 DAP, 1% greater 26 DAP, and 1% lower 42 DAP. Cover crops did not affect potato yield at Oakes, though negatively impacted yields at Carrington with 18% greater marketable yield without a cover crop. The results of this experiment support the consideration of cover crops in an irrigated potato system as a means of additional weed control. Longer maturing potato cultivars present a problem as they require resources during the same part of the season that is critical for cover crop biomass accumulation.
A field experiment was conducted at Fargo, North Dakota, from 2009-2010 and repeated near Carrington from 2010-2011 to evaluate the potential for weed control and potato yields using cover crops in non-irrigated potato production. Cover crop treatments included no cover crop, triticale, rye, hairy vetch and rye/hairy vetch. The hairy vetch winter killed at Fargo and was replaced with turnip/radish and canola cover crop treatments. Cover crop termination treatments for both locations were disk-till, roller-crimp, and herbicide. The results were analyzed as a RCBD with a factorial arrangement and as a RCBD with a check. Locations were not combined due to winter-kill of hairy vetch in 2009-2010 and replacement with turnip/radish and canola. At Fargo compared to the no cover crop treatment, plots with a cover crop had 17% greater weed control 17 DAP, 15% greater at 34 DAP, and 5% greater 49 DAP. At Carrington, plots with a cover crop had equal weed control to plots without a cover crop planted at 12 and 28 DAP, though plots with a cover crop had 5% greater weed control at 47 DAP than those without a cover crop. Yield in Fargo was low on average due to cover crop treatment and soil conditions. In Carrington, average marketable yield from the no cover crop plots was 35% greater than cover crop treatments. The results of this experiment support the consideration of cover crops in a non-irrigated potato system as a means of additional weed control.
Introduction:
Cover crops are any plant grown for a set purpose in between times of cash crop growth (Brady and Weil, 2008). Cover crop integration into conventional agriculture rarely occurs today due to growers’ ability to easily overcome production problems with pesticides, fertilizer, and crop rotation. However, more growers are beginning to consider the use of cover crops to enhance soil retention, soil and environment quality, as well as to provide alternate methods for fertility management and pest control (Blevins et al, 1990).
Furthermore, cover crops are often relied upon in organic and sustainable agriculture systems and continue to increase in acreage each year with North Dakota ranking second in the U.S. for organic crop production (Knopf, 2011). Over the last three growing seasons, from 2008-2010, potato production in North Dakota ranked fifth in the U.S. for potato acreage, with an average of 34,000 hectares devoted to this crop. Weed control in organic potato production relies on the effectiveness of cultivation, harrowing, and weed suppressing cultivars (Beveridge and Naylor, 1999). Unfortunately, regular precipitation and slow soil drying due to the clay soil texture in the Red River Valley, make timely cultivation difficult and often impossible. Growing winter annual cover crop species provides a potential alternative early season weed suppression method. The growing season found in the Upper Midwest, specifically North Dakota, will limit many aspects of cover crops due to shorter growing seasons than other locations in the United States (Snapp et al, 2005; Teasdale, 1998).
This research evaluated the effects of cover crop, termination method, and potato cultivar on weed control in potato. The first objective was to determine if cover crops improved weed control in potato production where chemical control was not desired. The second objective was to determine how cover crops influenced potato yields. Results of this research will be relevant to potato producers who are considering adding cover crops to their potato production systems.
Project objectives:
This research evaluated the effect of cover crop, termination method, and potato cultivar on weed control in potato. The first objective was to determine if cover crops improved weed control in potato production where chemical control was not desired. The second objective was to determine if cover crops added or detracted from potato yields. Through this research it is anticipated that potato producers could add cover crops to their potato production in a way that would benefit their unique cropping system.