I'm talking about 50 trees per hectare or 75 trees per hectare, so it is not per se forestry.
What we are trying to do here is to capture the nutrient-cycling aspects, the carbon sequestration aspects, the biodiversity aspects, and the ecosystem services aspects that could be derived, even at a low density of trees in the agricultural systems, in order to reduce runoff, nutrient loading, and enhance bird diversity and microfaunal and macrofaunal diversity. This is what we are trying to achieve.
When it comes to the landowners, they were paid to remove trees in order to allow big machinery. Now we are trying to ask them to put the trees back, so there's a lot of education that is needed.
I should say that these trees, when they are integrated into the agricultural landscape, need a certain degree of management, like pruning of branches. If you look at these trees, the branches have been pruned. Why? We need to allow more solar radiation in order to continue productivity. The tree row orientation is also important. You can't plant east-west in Canada, because you will get less productivity. You have to plant either north-south or northwest-southeast, because we are in the northern hemisphere.
A lot of education is needed. There's a management aspect that's needed. Landowners are willing to do that, provided there's a policy to support it. The issue, as I said, is that they're asking why they should invest for the public good and what they get as a result of that.
The science is not disputed. Actually, the science has been proven globally. I just mentioned that in the COP22 conference in Morocco, agroforestry was given a session, and it's being promoted to be integrated into the agriculture policy of the sub-Saharan African countries, because that is the only way they can increase resilience to climate change in the agricultural sector.
Trees can modify microclimate. The evapotranspiration losses can go down, and there's more moisture. We have shown through research that 3% more moisture can be retained as a result of having trees. In a dry year, when agricultural crop productivity declines, the reduction in yield in a tree-based farming system is comparatively less because of the microclimate modification. It can increase diversity of soil micro and macrofauna, which enhances the organic carbon input as well, from the leaves, and in turn, the soil's organic carbon.
The science is there and landowner acceptance is there. They are not disputing anything that you say. They can see that their animals will benefit, because the silvopastoral system not only contributes to the heat stress reduction, but it also contributes to the cold stress reduction in the winter months. If you have coniferous trees, that contributes to windbreak and cold stress reduction, which enhances productivity in the livestock because of less stress.
Some have adopted such land use systems, but the issue is that there is no policy or incentives to back the adoption of them.