Embracing Sustainable Food Production: Integrating Trees and Crops

To the vegetable grower, trees offer a great opportunity for increasing the variety of food grown in the same field or garden, while bringing other benefits to your crops. Not just optimizing yield, but also improving soil, managing pests and water, increasing biodiversity, and reducing costs.

The following excerpt is from Silvohorticulture: A grower’s guide to integrating trees into crops by Ben Raskin and Andy Dibben. It has been adapted for the web.

Why Integrate Trees and Crops?

On the very simplest level, trees are brilliant. Since they evolved 360 million years ago, they have been a central element in the evolution of all life on Earth, providing habitat and valuable resources. The removal of trees from farming landscapes has had subtle but profound impacts on both production of food and also the wider environment. It is time we reintegrated them into all our food-producing landscapes.

To the vegetable grower, trees offer a great opportunity for increasing the variety of food grown in the same field or garden, while bringing other benefits to your crops. Wind protection, soil health improvement, flooding offsets, drought management, soil erosion reduction and shade are the key benefits that can be exploited by introducing trees. These benefits might be tools to address inherent historical problems on your site, such as soil erosion, wind or waterlogging.

They will also be relevant as climate change takes a grip, helping to solve problems you have not experienced before. Whether you have already been majorly affected by climate change or not, now is the time to future-proof your vegetable production from these challenges that are sure to affect all food producers over the next twenty years.

What Can Trees Do for Me?

We have made some bold claims about the potential benefits of trees. How this potential is realized is truly down to treating each site as a unique opportunity. Each field and garden demands a unique design to truly maximize benefits. Identifying current and potential problems on your own site is the single most powerful step of the design process. Take your time to understand and assess this.

Discover other benefits, such as new crop lines and fewer farm inputs, on top of this initial assessment. Many trees can fulfill the problem-solving role of system design, and more often than not a diversity of tree species will be needed for this role.

A standard single apple row with managed grass understorey at Close Farm. On the left, fleece covers one of the mixed vegetable beds. Photo courtesy of Ben Raskin.

The truly creative part of system design combines solving your specific site challenges with providing a usable end product. This product might be a new crop line that you can sell – edible, floral, medicinal or drinkable. Often overlooked, however, is the financial and sustainable impact of reducing your production inputs.

Once you factor this in, a whole new level of benefits can be realized. Propagation compost, general purpose compost, predator population boost, pollinator population increase, trellising materials and irrigation reduction are all a result of growing trees, without which you would see us adding to the burden of what is already a resource-hungry activity.

Witness the environmental impact of your inputs by producing them locally. Reduce the financial impact of your inputs by producing them yourself.

Which Trees Fulfill These Objectives?

Having identified the problems you wish to solve, and the new crops and farm resources you can produce on site, you need to choose which species will fulfill one or many of these objectives. How you choose and lay them out in the field or garden is the truly creative and exciting part of the design process, translating theory into reality.

The individual qualities of different tree species, such as rooting behaviors, canopy shapes, heights, rootstocks and growth rates, are all things to become intimately aware of, not just in one moment but as they evolve over time. When considering sellable crops, you have to understand if they will thrive here now or in the future, and if they can be sold. When trying to reduce farm inputs, you also need to work out if you can produce meaningful amounts of a particular resource.

How Will the Trees Interact with Crops and Time?

Having decided which trees to plant and how to arrange them, the fine tuning of the design process is understanding how this arboricultural intrusion is going to interact with your vegetable crops. To achieve this, you need a realistic grasp of the complex interactions between different tree and vegetable species. Balancing competition for light, water and nutrients is the key; and understanding how these interactions happen over a seasonal and multi-annual time scale is crucial. Extrapolate your design over a 10-year period and visualize every year, trying to run different scenarios of what real-world incursions are possible: predation, market changes or intensifying weather for instance.

When Does Each Stage Need to Happen?

Plan. Prepare. Procure. Plant. Protect. Problem-solve. And most importantly, ENJOY.

Annual vegetables are an exhilarating yearly addiction, enslaving many vegetable growers. Adding the long game of trees to your system results in a deeper and more reliable, resilient and profound presence to your production system.

Life is short. True happiness lies in enjoying the moment but keeping half an eye on the future. A philosophy the authors have bonded over and both see embodied in agroforestry of all forms, a passion it has been a pleasure to share.

Recommended Reads

Creating A Plant Grouping: Edible Forest Gardens

Low-Risk Silvopasture: Chickens, Turkeys, Guinea Hens, Ducks and Geese