The Courier & Advertiser (Angus and Dundee)
Low uptake is a puzzler
Eu-funded studies to find out why farmers slow to adopt successful system
Intercropping is the concept of growing two or more crops together in the same space and the same time.
The use of intercropping is being adopted by farmers who wish to maximise nutrient use efficiency while also improving soil health and quality. Such aims are a necessity and can deliver these benefits in tandem with improved profitability. However, intercropping does not feature strongly as common practice in the UK.
In Scotland, intercropping is usually deployed as clover-grass swards for silage or grazing. A few enthusiastic, progressive and environmentally-conscious Scottish growers have developed successful arable intercrops too. But in general these are rare within arable systems in Scotland. Such farmers deploy intercrops in the form of cropteams often involving a legume species such as peas or faba beans.
This combination exploits the capacity of the legume to meet its own nitrogen requirements via biological nitrogen fixation, a natural symbiotic process whereby soil bacteria, referred to collectively as rhizobia, infect legume roots and become entrapped within the core of legume root nodules. Here they fix atmospheric nitrogen gas into a biologically useful form of nitrogen and so promote legume plant growth, also promoting the growth of the nonlegume, usually a cereal, with which they co-exist.
The science literature shows that this type of intercropping could be successful in UK farming systems, and the in-field findings by farmers show that it works in practice too.
Questions remain as to why mainstream farmers are slow to adopt intercropping. Two Eu-funded industry-science partnerships at the James Hutton Institute are addressing the reasons for this low uptake.
The two projects, DIVERSIFY (www. plant-teams.eu) and TRUE (www.trueproject.eu) are identifying ways to overcome barriers that arise through lack of knowledge of the practice, availability of appropriate machinery for intercrop management and harvesting together with the ability to process harvested products and use them downstream in the supply chain.
These projects are closely aligned with Scottish Government-supported initiatives to optimise barley-pea intercropping, which showed 20% higher yields than monocropped barley.