Ixolich

Threaten to consume the earth with a black hole unless they are paid a sum of one trillion USD.
Actually, that may not be a bad idea to keep funding going.....

It's actually a bit easier to answer this by coming at it from the opposite direction. Boreal forests (also known as taiga) are dominated by coniferous trees - pines, spruces, etc. So let's look at what other types of forests look like. (Note that this is a simplified explanation.)

In more southerly climates (like most of the US) forests are dominated by deciduous trees which drop their leaves in autumn/winter. What happens then, if there's no human input (eg nobody rakes the leaves and bags them for disposal)? The leaves will dry out and start decomposing. They get "eaten" by various bacteria and fungi in the soil, and their decomposed bodies turn into new soil, rich in nutrients. Deciduous forests are essentially in a cycle of pulling nutrients from the soil so that trees can grow, then returning nutrients to the soil in the form of decomposing leaves. This cycle being relatively constant means that there's thick soil (as there's constantly more being made from the leaves).

But leaves don't fall in boreal forests with coniferous trees. That means that they're not replacing soil as much, which means that the soil tends to be thinner and more lacking in nutrients. Doesn't mean that nothing will grow, but it means that fewer things will grow, you have to be more careful about how you're choosing what to plant.

Hey Keith! Big fan of your channel. I'm currently living with my parents as I pay off my student loans, but I'm looking to be moving out next year and hoping to start a food forest of my own.

My main issue is the three-dimensional design aspect. I can do the two-dimensional tetris like none other, but thinking about how it'll work when the plants start to grow messes me up. How do you go about choosing what plants should go in what guilds so that they work together? How do you design it so that a larger tree or bush doesn't end up shading over the lower level plants as they grow?

Okay, that makes sense. I'd been under the impression that the early stages of the guilds were the same as we'd want them to be once they're grown - eg keeping a companion nitrogen fixer for maintenance.

I think the part that had me confused was the increased efficiency with fewer pieces/less dense growth. Just seems backwards at first, you know? As things get shaded out and expand away from the center tree, there's fewer pieces per sq ft so you'd expect less efficiency.