Agriculture takes
a huge toll on the environment. But there is a way
to make it more eco-friendly that has literally been
around for thousands of years. And it has to do a lot
with these seemingly boring, but surprisingly powerful trees. Right buddy? Industrial agriculture has
major environmental drawbacks: 26 percent of all global greenhouse gas
emissions come from agriculture. Its crop monocultures suck
out all the nutrients out of the soil. And lastly, agriculture
takes up enormous amounts of land. So, how are some random
trees supposed to help with all that? It's called agroforestry. The system combines conventional farming of crops and animals with different types of trees. And apparently it reduces emissions, requires less fertilizer, and it's even scalable! I mean that's like winning the
environmental lottery. To find out if that actually is the case,
I'm visiting Jochen Hartmann. His family has lived
here for 19 generations. Yet he's one of the first
to adopt what's known as the alley cropping system in Germany. "Trees in the fields isn’t
how they teach farming, is it?" "It takes some time getting used to. You often think: 'What on Earth are you doing here?' Because we learned:
the larger the field the better. Now we’re downsizing them which
costs me some effort, but it’s great!" Jochen opted to
plant poplars across his fields. They grow fast, are easy to manage and cover about 10 percent of his 200 hectares. They're mixed with his crops and hens –
where we are headed now. "These poplars
have been growing for five years." They are about ten meters tall now, meaning there's
a lot of CO2 stored inside them. The ability of trees to absorb
CO2 and mitigate climate change is a major selling point for agroforestry. And they also work
great in combination with hens. 500 of them! And you see like that immediately
after they come out of the truck they start to eat. So, they are not only
eating what they would be fed in a conventional farming method,
but they eat what they find out here and that's really
sustainable because most of the CO2 emissions associated with
raising chickens come from their feed and when you do it like this,
you don't have to grow it elsewhere. What otherwise would be
done in three separate places: raising chicken, growing food and trees, is now done in
one place which reduces land use. The trees' leaves also offer protection
from predators and create a cool place where the birds can take a quick nap. Once the leaves fall the
hens trample them into the ground, which helps the soil regain nutrients. To be clear: This doesn't free
these hens of their environmental impact. Some of their feed
is still grown in monocultures. But at least in this case, some of the CO2
that is emitted along the supply chain, is being compensated by the trees on
the same land as these chickens grow up. Right buddy? One study says that converting
9 percent of Europe's farming land into agroforestry systems
could offset between 2 and 43 percent of all European
agriculture CO2 emissions. The range is so wide because
agroforest types can vary tremendously: from small hedgerow
systems that store next to no CO2 to large tree systems. "But if we are looking
only at our systems we have here, like these alley
cropping systems, we would say we are around 1, 1.5t
per hectare carbon sequestration." This is Dr. Sonja Kay. She has been researching all kinds
of agroforests for the past six years also assessing their CO2
mitigation potential in an EU funded study. "And when we are comparing that with the total carbon amount
emissions we have in Europe, then we are around
10 percent of the agricultural part which we could store with or which
we could mitigate with agroforestry systems." Still a great potential! There is one caveat though. If the trees that are
grown are used as firewood – like these will be in the future – about 70% of carbon dioxide
is re-released into the atmosphere, which kind of goes against
the idea of carbon sequestration. These trees will be chopped
down to about 20 centimeters above ground once they are fully grown. Nevertheless, underground
the trees have other positive effects besides the CO2 storage above ground. They can add to the soil's quality and
potentially reduce fertilizer usage and emissions. Yes! 'Modern agriculture solving the
problems it created!' You'd think. Agroforestry is actually ancient. Different forms of it can be
traced back thousands of years. In these medieval paintings
you can see pigs being released into the forest to
feed on different types of nuts. Or Indian home gardens
that combine different ground crops with tall trees
even date back to 7000 BCE. It disappeared largely
in the first half of the 20th century because it was seen as inefficient. Scattered trees
didn't really work well with tractors
and large farming machinery. Because Jochen's
poplars worked so well for his hens, he decided to extend
the system across all his fields. These were planted a couple of
months ago and the wheat needs to be pulled
otherwise the trees wouldn't make it. In the first year in particular agroforestry
strips are more labor intensive. “We’ve got less arable
surface but we harvest the wood later. And you can feel the
wind and the heat now. If that continues for another three weeks
things will gradually dry out here. The trees form a wind break, and anchor the
moisture better in the ground, and I’m quite optimistic
that the yield will be fine." This protection from wind erosion becomes a little more
visible on a more mature field. The trees basically block the wind
from blowing right across all the fields, preventing nutrient and
moisture-rich soil from being blown away. Some yield is lost at the sides because
the trees also want their share of water, but it's balanced out in the middle. And even though it might not look like
it, these trees can boost biodiversity. “Wind always makes them hide away a
little. But hoverflies are beneficial insects. Look there’s a couple there." Especially for insects, worms and fungi. "There! The dung
beetle here – and he’s rolling." "But there aren’t that many
insects in this poplar strip, are there?" "They were only planted last year. We’ll add multiyear wildflower strips to the left and right
as buffer zones. In particular because we can’t get closer than three
meters to the trees for harvesting. So we’ll plant wildflowers
there and that’ll double the effect." "Right! Let’s get started." This helps creating a
better habitat for wild bees. So, it's not just about sticking some
poplars between two monocultures really. "When you keep them in
a single strip and place them well, then it’s no problem at
all for the large machines. They don’t get in the way and
give us nothing but advantages against wind erosion. I can hardly wait to see what it looks
like over the next few years here." The system can be scaled
up easily for even bigger farms. Like here in Spain or Kenya. But it's also practiced
on smaller farms in countries where agriculture is more fragmented. Like here in India. So, if agroforestry has so many advantages,
why don't we just convert every farm into an agroforest? "There are some areas
where you should not plant trees. The soil is not thick enough. So, the trees cannot stand
there, or something like that. So really before you're
starting growing agroforestry you should be aware, that
you check if it's possible or not." The soil of watery rice fields or hilly
regions can present a challenge for trees. Besides which the initial costs of establishing an agroforestry system is quite high and isn't subsidized in Germany. Yet. Agroforestry is a great system
with a lot of potential bringing animals, crops and trees together also
makes our agriculture more resistant to extreme weather –
which will be really useful in the future. But it's also not
the one solution to all of our problems. Still, compared to conventional agriculture
it's a really good starting point for more sustainable farming. If you like this video as much as
I like to work with these chickens, please subscribe to our channel. We post videos on the environment each Friday. I think I need to get out of here.
