Integrating winter camelina into maize and soybean cropping systems

Authors: BERTI, MARISOL - North Dakota State University; SAMARAPPULI, DULAN - North Dakota State University; JOHNSON, BURTON - North Dakota State University; Gesch, Russell - Russ

Submitted to: Industrial Crops and Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/6/2017
Publication Date: 6/12/2017
Citation: Berti, M.T., Samarappuli, D., Johnson, B.L., Gesch, R.W. 2017. Integrating winter camelina into maize and soybean cropping systems. Industrial Crops and Products. 107:595-601. http://dx.doi.org/10.1016/j.indcrop.2017.06/014.
DOI: https://doi.org/10.1016/j.indcrop.2017.06/014

Interpretive Summary: Winter camelina has been shown to have good potential as a winter hardy cover crop in the northern U.S. that can also be harvested for its seeds. The dominant crops in the upper Midwest are corn and soybean. These two crops, however, are often harvested too late in the fall to allow good establishment of a cover crop after their harvest. Therefore, an experiment was designed to determine whether good establishment of camelina could be achieved by broadcast seeding between rows of standing corn and soybean at different times. Additionally, we measured the impact that the potential competition from camelina might have on yields of these two major crops. The same experiment was evaluated across three different environments, two of which were in North Dakota (Fargo and Prosper) and one in Morris, Minnesota. Results demonstrated that when camelina was planted between rows at the same time that corn and soybean were planted, competition from camelina reduced corn and soybean yields. However, broadcast seeding camelina between rows after corn and soybean had matured to more than the 4- to 5-leaf stage, did not reduce yields. The establishment of camelina greatly depended on timely rainfall, and poor stands developed during periods when rain was lacking. The fall and spring soil coverage offer by camelina plants tended to be low for seeds sown into standing corn and soybean, and the greatest coverage was actually achieved by planting after crop harvest. Nevertheless, if planting winter camelina as a cover crop into standing corn and soybean, it is recommended that it not be planted until after the 4- to 5-leaf stage of development to minimize yield loss due to competition. This information will benefit crop consultants and extension specialists as well as other researchers working on camelina as a cover crop.

Technical Abstract: Camelina [Camelina sativa (L.) Crantz.] is an industrial oilseed crop in the Brassicaceae family with multiple uses. Currently, camelina is not used as a cover crop, but it has the potential to be used as such in maize (Zea mays L.)-soybean [Glycine max (L.) Merr.] systems. The objectives of this study were to determine the agronomic performance of intersowing winter camelina [Camelina sativa (L.) Crantz.] as a cover crop into standing soybean or maize crops prior to their harvest and determine the nutrient scavenging ability of camelina sown in autumn. Experiments were conducted in Fargo, ND in 2014, Prosper, ND in 2015, and at Morris, MN in 2014 and 2015. The experimental design was a randomized complete block design with a split-plot arrangement with three replicates. The main plot was the row spacing; the sub-plot was the maize or soybean growth stage at relay-sowing defined as the sowing of winter camelina into the growing maize or soybean stand. Winter camelina was sown on four different sowing dates: Date 1 (SD1), at the same sowing date as maize and soybean, Date 2 (SD2) at V4-V5 of maize and V3-V4 of soybean growth stages, Date 3 (SD3) at "silking" of maize and R1-R2 stage of soybean, and Date 4 (SD4) after maize and soybean harvests. Camelina establishment into standing maize and soybean largely depended on rainfall after sowing. Camelina intersown on the same date as maize and soybean resulted in lower grain and biomass yield of 14 and 10%, respectively, for both crops; whereas, intersowing after V4-V5 stages had no significant effect. Results indicate that camelina intersown after V4-V5 stages will likely avoid competition with the cash crop. Camelina establishment and winter survival was best when sown after maize and soybean harvest, and tended to be greater in soybean. Yet, there are many unanswered questions on camelina intersowing management. New research will allow optimization of intersowing management to increase yields of both crops while enhancing ecosystem services.