It is all about having options.
Consider a hybrid poplar tree. It grows biomass. It does not produce "human quality" food. It does not produce much mast or forage for domestic animals or wildlife. It is not a very good timber tree. It is not even a very good tree for fire wood. It does one thing very, very well. It grows fast.
Consider an apple or a chestnut tree. It produces "human quality" food. It also produces "animal quality" food. While not very good timber trees, chestnut wood is durable and make adequate fence posts, something that cannot be said for hybrid poplar. Regarding firewood, all trees produce wood that burns. Orchard trees require trimming and that automatically produces firewood as a byproduct. Apple wood is excellent for smoking meats. It is flavoring. Apples and chestnut trees offer me more options than hybrid poplar.
In deciding the order of what is highest use, I think about the Inuit (Eskimos). When confronted with short supplies, they always chose to eat blubber rather than burn blubber. So, to me, that means that trees that produce human quality food should be at the top of the list.
Trees that produce food for wild and domestic animals are next on the list. Food is food. Direct food is more thermodynamically efficient. Food that is not palatable to humans can be cycled through a pig or squirrel or deer and thus become delicious, high quality food, albeit at a higher cost.
When forced to choose between trees that produce excellent wood products or firewood, I choose the wood products. The production of poles, posts and dimension lumber always results in "tops" and scraps suitable for firewood. Choosing trees that produce construction materials automatically gives me firewood as a byproduct. The reverse is not always true.
There are niche players and cross-overs. Black Locust does not produce an appreciable amount of human quality food (a bit of honey) but it fixes nitrogen and makes great fence posts because they are highly rot resistant. A farmer always needs three more gates and six more fence posts. Always. Black Walnut produces nuts. Some selections produce a lot of nuts. Some just a few. But it is one of the premier hardwood trees in the Eastern United States. And the smaller pieces make fine fence posts because it too is rot resistant.
But as a general rule I follow this heirarchy:
- Trees and plants that produce significant amounts of human quality food with modest amounts of effort.
- Trees and plants that produce significant amounts of animal quality food with modest amounts of effort.
- Trees and plants that produce durable "construction" materials in large quantities. Prime windbreak species are a subset of this category but only when they are upwind of your residence.
- Trees and plants that produce biomass.