What is Agroforestry and Why it Matters for Food?

Agroforestry is one of those vague and nebulous terms which broadly speaking means farming with trees. But, I’ve yet to see a British farm that doesn’t have a tree of some sort in and around the place. So, we focus down in on the two key methods most prevalent in the UK; alley cropping and wood pasture (linked blog).

Alley cropping is a way of converting an existing open arable field, into strips, or alleys of cereal crops, cropping the ally bordered by rows of fruit or nut producing trees. These alleys can be adapted to the width of farm machinery, to ensure it’s a practically viable change for farmers. The alleys would typically be planted with annual cereal crops, so wheat or barley predominantly. Though this can include all manner of different crops, one of the UK pioneers of this method plants beetroot for example! See below an example of black walnut with Barley from a French alley cropping system. 30 metres is a typical width, and, when aligned North-South, the impact of the shading is minimal until year 15, by which point the crop of nuts more than compensates financially for the slight reduction in cereal yield. 

This ability to produce more from the field, whilst simultaneously addressing key environmental concerns, is one of the reasons we advocate for agroforestry. It’s this combination of taking the good things about the modern farming system; the yields and efficiencies, whilst addressing the downsides around soil erosion, biodiversity loss, and excess nitrate run off, that makes the prospect of widespread agroforestry a win-win. It’s miraculous that in the space of a 100 years, we’ve made obesity a bigger problem than hunger in our society, so we would be wise to caveat all critiques of our current food system with this in mind.

Alley cropping also has a host of more subtle, yet no less important, benefits. The presence of the trees both warms up the soil sooner in the spring to aid germination, but then helps regulate ground temperature, preventing added heat stress on the crops by reducing evapotranspiration rates in high summer. As I write this, the UK is sweltering in 40 degrees in June. The ability of farm systems to mitigate heat stress during summer, looks set to become an essential factor in all farm planning. Take a deep dive into the metrics and science behind these figures here (link to “Agroforestry and The Science : Farm Metrics Fit for The Future”)

It’s a slightly more sizeable change than a wood pasture system, as it tends to require changes in behaviour and management method which require buy-in and adaptation from several different contractors. How to adapt, drilling, spraying, harvesting operations to a reduction in field size can be a challenge, but perhaps a challenge that future resilience demands we face up to. For a deeper dive into the hurdles to uptake, check out (link to “The Political Economy of Agroforestry” blog).