Soil nitrogen sampling in adjacent fields of winter beans (Vespa) and winter wheat (Gleam) will be undertaken during year one of the rotation and then again as the fields both move into wheat in the second year (variety tbc). A comparison of yield (quantity and quality) of the first wheat (following winter beans) and second wheat (following winter wheat) will be undertaken.
We hope that this trial will help build data available to support the role of pulses in an arable rotation, and assess any tangible impact that incorporating pulses might have in terms of nitrogen benefit to the following cereal crop.
We also use two or three year legume fallows as break crops on our farm (under either a Higher Tier Countryside Stewardship Scheme or the SFI) which will also be coming back into the rotation in future years, and similar analysis could also be undertaken – in 2025, we intend to put a two year legume fallow back into either winter beans or winter wheat (or split the field and do both) and repeat the analysis above.
Alternatively, if the data gathered supports the idea that the cereal crop following the winter beans would benefit from nitrogen fixed in the soil by the pulses in the previous crop, we could consider a variable nitrogen application trial in a wheat crop following a bean crop, to assess whether a reduced rate of inorganic nitrogen can be applied to achieve the same quality and quantity of yield in a wheat crop following pulses.
There are many avenues in which this initial dataset can be built upon, and we hope to be able to pursue at least one of the in future years.
