With one half drilled in November and the other drilled in April, this two part experiment offers an insight into multiple intercrop mixtures with the winter half focussing on different cereals while the spring half focusses on different legumes.
To have a look around the experiment, use the viewer below to drag around the 360 degree image of Intercrop 2020.
Winter Intercrop 2020
Bean intercropped establishment
The establishment of beans within the intercropped treatments has been greatest within the wheat intercropped treatments with the oat and barley intercrops appearing to somewhat limit the establishment of beans.
Error bars refer to 2 standard errors
Cereal intercropped establishment
The cereal establishment showed very little difference between the intercropped treatments, except for each 25% cereal: 75% bean treatment. These show a marked increase in establishment over the other intercrops as well as Sole Crops.
Error bars refer to 2 standard errors.
Weed plant counts per metre squared-29/04/20
Results showed the intercropped plots had a weeding effect when compared to the Bean SC while generally not having a weeding effect when compared to the Cereal SC, with exception to 75% Wheat : 25% Bean treatment.
The weed plant counts were taken during the cereal stem extension stage, when the canopy of the crop was beginning to close over the ground and compete with the weeds.
The oat plots were not able to receive a pre-emergence herbicide as there was not one available that was suitable for both oat and bean. As a result the oat intercropped plots had a much higher weed population than the other treatments despite having been weeded using a finger tine harrow.
A weed biomas reading will be taken closer to harvest.
Error bars refer to 2 standard deviations.
Seed rates- Winter and Spring
Seed rates of the treatments shown as seeds per metre squared for Winter and Sring sown intercrops
Other intercrop services
Scaffolding for Legumes
One of the difficulties with growing and harvesting some legume crops such as peas, is their tendency to lodge and fall over. One of the aims of inercropping cereals with legumes is to provide a structure to hold the legumes upright.
In the photo to the left you can see a spring pea plant already beginning to reach out and hold onto the wheat plant which will support it as they both grow upwards together.
Nitrogen (N) catching
For legume growers, excess soil N can be problematic with weeds in bean crops, especially where there are gaps in the canopy. Intercropping cereal into a legume crop will mop up excess N, leaving little N available for problematic weeds.
For low input systems, intercropping legumes into a cereal crop can increase available N for the crop while also adding nutritional value to feed crops.
The image to the right shows wheat plants from intercropped seeding ratios of 25:75, 50:50, 75:25, 100:0 (cereal:legume) left to right.