Trials aimed at combining maize cultivation and inter-row cover crops were carried out as part of the Climaveg project led by the Pays de la Loire Chamber of Agriculture. The objective: “to study the lever for permanent land cover in response to climate change”, summarizes Mathieu Arnaudeau, agronomy advisor at the Pays de la Loire Chamber of Agriculture.
Placement of plant cover IN corn silage it makes it possible to have a cover present and well established at harvest time to perform an additional mowing before planting the cereal. “We are trying to find a solution to use this very short intercropping, during which we often have soils that become contaminated,” explains Mathieu Arnaudeau, agronomy adviser at the Pays de la Loire Chamber of Agriculture.
The experiment made it possible to test the technical feasibility of placing the cap. of legumes were chosen for the first year of the experiment, with white clover, red clover, berseem clover and Greek fennel.
We penalize corn but maximize canopy yield
The tests made it possible to evaluate corn silage yieldand cutlery with three inter-row different; one at 75 cm (classic row spacing), one at 37.5 cm (transverse planting) and a large spacing of 1.5 m with two rows of corn so that the seed density is not too high.
“Just us widen the gapwe have one yield loss, explains Mathieu Arnaudeau, about 1 t, 1.5 t DM per hectare”. This loss of yield can be compensated by the fact that the wider the space, the more the canopy develops. “We were able to climb up to 3.4 or 3.5 t of dry matter thanks to the cover, which took place between September 14 and October 25. »
With a row spacing of 75 cm, a yield of 15.4 t corn silage DM was taken with a covered land, to which 1.8 t DM are added from mowing the canopy. With the same space in a bare earth, the recorded yield was 14.1 t DM. For the rest, “just us increase row spacingwe penalizes corn, but the canopy yield is maximized. »
The experiment is set to continue, with the installation of capacitive probes (which allow the degree of soil moisture to be measured) to determine the impact of coverage on water managementand irrigation.
The main point of vigilance concerns corn weeding. “There are few programs that can properly clean corn without affecting canopy development. » As part of the experiment, post-sowing/pre-sowing weeding with an anti-sprouting agent was carried out and had no effect on cover establishment, sown in early June at 40 kg/ha (target density 20 kg/ha ), at the 8 – 10 leaf stage of corn, i.e. approximately one month after weeds. No recovery was done, as this would have displaced the cover placement.
The cover has also benefited from one favorable rainfall “It is better that at the time of planting you make sure that the weather conditions allow the canopy to emerge well. Last year, the cover crop planted at the beginning of June benefited from 15 mm of rain within 10 days of its creation,” the advisor notes.