Do you know trees actually do better with a friend? Take a stroll through a nearby forest some afternoon and pay special attention to the placement of the trees, their proximity, and how well they are growing. The forest can be a great guide as we grow within our home landscape. Trees planted closer together will benefit one another more as apposed to trees planted on either side of your property.
Trees have the ability to communicate with one another and can also share resources. For example, a douglas fir tree and a birch tree can transfer carbon between them via mycelia (the vegetative part of the fungus in the soil).
To learn more, check out this Ted Talk!