Agroforestry’s role in wildlife conservation and food security

Becca Rimmel, a farmer in upstate New York, has been noticing some changes on her property — the kingbirds and woodcocks have returned. A former naturalist, she’s recorded nearly 90 species of birds on the farm so far.

The operation, producing pasture-raised pigs, chickens, goats, rabbits and mushrooms, is not your typical affair. Rows of chestnuts and apples grow alongside winter squash, while pigs and chickens graze in the shade — providing fertilizer and controlling the hay and grass. Rimmel and her partner also planted four acres of native trees and shrubs along a creek in 2019, installed fencing to exclude livestock from the water and dug several vernal pools.

This mishmash of trees and cultivation is agroforestry. Yet this practice of planting trees and shrubs among crops and livestock fields is uncommon in the U.S. — less than two percent of farms do so.

However, agroforestry is gaining steam — to support its adoption, the U.S.D.A. recently granted $60 million to transform 30,000 acres of land with this practice of combining trees with crops or livestock. It’s also attracting renewed interest in Europe, where around nine percent of agricultural land already uses agroforestry.

The ancient roots of agroforestry

Despite its recent popularity, agroforestry is a traditional farming technique used around the world for thousands of years.

Yet, despite the benefits, many agroforestry systems were wiped off the map in past decades. For instance, the United Kingdom lost 50 percent of its hedgerows since World War II — mainly due to agricultural mechanization and intensification.

Benefits to the farmer

While cleaning up those fields undoubtedly had advantages, it also eliminated the benefits farmers received from these systems.

For instance, studies have shown that having natural habitat on a farm can attract pest-munching predators. In temperate agroforestry systems, invertebrate predators — such as spiders, ladybugs and ground beetles — were 24 percent more abundant versus control fields without trees. Many pests were also less abundant in agroforestry systems.

Rimmel also noticed a similar benefit on her farm.

“There’s just a variety of huge biodiversity there that are helping to keep our systems going in a natural way…” said Rimmel. “We don’t use any pesticides or herbicides. So, that’s a really important part of it.”

Similarly, other studies found that agroforestry reduced farmers’ need for land or resources such as light, water and nutrients by a range of 14 to 100 percent compared to a monoculture. Reasons why include improved soil fertility, increased soil moisture and a better microclimate.

Similarly, other studies found that agroforestry reduced farmers’ need for land or resources such as light, water and nutrients by a range of 14 to 100 percent compared to a monoculture. Reasons why include improved soil fertility, increased soil moisture and a better microclimate.

In addition, agroforestry systems can extend the growing season in some locations and shade crops from extreme temperatures. Agroforestry also protects livestock from severe weather, which may be exacerbated due to global warming. For instance, providing shade to cattle can increase weight gain and milk production. Plus, agroforestry mitigates climate change itself by absorbing carbon.

Further, agroforestry can stabilize farmer’s pocketbooks.

“In most agroforestry systems you’re having more than one crop growing — maybe a tree crop and a row crop,” said MacFarland. “It may be a long-term timber harvest and a shorter-term livestock annual income, or all different kinds of combinations. By having that diversification, you’re not putting all your eggs in one basket.”

Finally, agroforestry can help when people and wildlife collide. For example, studies have found that in Africa, fruit provided crop farmers with income and food if their ground crops were raided by wildlife. In Southeast Asia, planting edible plants in an agroforestry buffer zone around fields may stave off elephant crop raiding.

A boon for wildlife

“Windbreaks have been shown in the plains to have 108 different bird species and 28 species of mammals in the Midwest,” said Gary Bentrup, a Research Landscape Architect at the U.S.D.A. National Agroforestry Center.

In addition, insect pollinators, native earthworms, reptiles and amphibians fare better under agroforestry than monocultures. This abundance of wildlife is due to food, shelter, protection from extreme weather, favorable microclimates and improved soil in agroforestry systems. Bentrup also explained that agroforestry blocks any pesticides that are drifting through the air, providing a lifesaving shield for pollinators and beneficial insects.

If that weren’t enough, animals also use agroforestry systems to travel between habitats.

“The Louisiana black bear was a species on the threatened and endangered species list,” said Bentrup. “There were these riparian corridors, more along canals than streams — they were only about 15 to 20 feet wide. But a study showed that bears were using these corridors to move between the forested patches in this very agricultural area, and they were a key piece that allowed the Louisiana black bear to actually come off the endangered species list.”

However, an abundance of wildlife can present a downside: livestock predators. Nonetheless, Bottomland Farm has come up with a solution.

“Instead of trying to trap or kill the fox and coyote that are here that live in the riparian buffer, we have gotten livestock guardian dogs,” said Rimmel. “So we’re trying to implement some predator-friendly ways to manage the property so that those animals can maintain their part of the food chain in those natural systems as well… I almost don’t want to say this out loud but we’ve had no predation problems with our poultry, especially this year.”

Hindrances to agroforestry adoption

However, despite the wide array of benefits, setting these systems up is not always easy.

Bottomland farm — which set up its riparian buffers and fencing thanks to a cost-share program with the Upper Susquehanna Coalition and the local soil and water district — experienced some of these challenges.

“It’s an upfront cost that doesn’t necessarily pay back right away and some of it we might not see actual cash from ever — like the riparian buffer, they’re ecosystem services that we can’t necessarily measure,” said Rimmel. “Even though there are systems in place to be able to use cost-share programs, understanding what those cost-share programs are and navigating through those programs can be challenging,”

In addition, a general lack of advice on establishing and managing these systems, along with a fear of crop losses can deter farmers. Even once the system is established, challenges remain.

“It’s a lot longer to get a return on your investment than a cropping system where you would plant something and you get it back in a year, and agroforestry systems sometimes go on the time scale of decades,” said Rath. “So it’s not immediately clear that both our risk management strategies that we have in place — like crop insurance and subsidies are set up to incentivize these practices… We know it’s a beneficial practice for a number of reasons, not just wildlife habitat, but a number of ecosystem benefits. And so how do we set up our agricultural system to incentivize that?”

Nonetheless, policies are slowly changing. For instance, in addition to the recent $60 million U.S.D.A. grant, the European Union’s Common Agricultural Policy offers financial incentives to farmers. The U.S.D.A. Natural Resources Conservation Service also provides financial and technical assistance to farmers for agroforestry projects.

Some nonprofits, such as Grow Ahead, also support agroforestry projects. For instance, they aim to replant Mexican coffee farms with new fungus-resistant coffee trees, add fruit and shade trees and establish a community nursery.

The future of farming

Cropland and pasture cover 38 percent of land globally, and as that percentage grows, it fuels climate change, pollutes the environment, and threatens biodiversity. However, sustainable farming practices, like agroforestry, offer a ray of hope in an otherwise harsh landscape.

To boot, farmers with sustainable practices are catering to an ever-growing crowd. The market for sustainable food is predicted to increase by nearly seven percent annually until 2032 — even with the typical premium price.

Finally, agroforestry operations may be set up to weather future challenges.

“I think with climate change, we’re going to be relooking at our agricultural systems and trying to figure out how do we make them more resilient to not just the long-term trends, but also the extreme climatic weather events that we are experiencing,” said Bentrup.

Who knew adding a little shade was so helpful?

Header photo by Andriy Blokhin/ Adobe Stock