The fastest-growing trees are the cottonwood and the Lombardy poplar. Neither of these is the best of firewood, though: pine burns excellently and isn’t too far behind the poplar or cottonwood. Black Locust –also known as False Acacia- grow quite fast and burn like coal. If you are planning on staying on a property for the long-term, plant a mix of larch, fir and Lombardy poplar. In most temperate climates across the US your poplars will be 40ft tall within 20 years.
We’ve already listed some of the fastest growing species, but there’s a much bigger range of broadleaves and conifers that are well-suited to firewood. To get the best idea of what to plant on your property, just look into what grows well in your local county area.
But even more important than what species grow well in your general locality is placing those species in the right place in your yard. Some trees – like willow and walnut – love getting their feet wet and should be planted at the base of slopes where seepage ends up. Other species – like birch – make great “pioneer” species: they’ll quickly grow up tall and strong in any kind of sun, wind and frost exposure to provide shelter for your main plantation.
What type of soil do you have to work with? Dry or damp? Alkaline or acidic? Clay or sand? Do you get frosts? Are there animals (like rabbits or deer) that could eat the saplings you plant?
To get the most out of your woodland, it may be possible to plan a no-waste sewage system to filter through the soil. This “black water” is not suitable for safely fertilizing vegetable gardens or fruit orchards, but it can certainly help speed up plantation growth and improve your wood yield.
To be completely self-sufficient in hot water and central heating, you’ll need as few as three hectares of woodland. Of course this varies a lot depending on species blend and conditions, but this is what you can aim for in a fairly wet, cool climate. If you plan to manage your wood by coppicing, you can divide three hectares into ten equal sections and harvest one section each year to provide you with your annual fuel needs, or about 8 ton of dried firewood.
Different species offer more or less calories of energy pound for pound of dried wood. If you’re really curious, you can check out this fuel/weight conversion table.
Now it’s time to figure out how much storage space you’ll need to dry your wood out. Ideally, you want to be cutting your firewood two-three years before you need to use it. Thirty-five feet cubed of freshly harvested firewood will weigh roughly one ton. Over the first year drying out in storage, that firewood will lose about a third of that total weight. Over the second 12 months, it will lose a further tenth of a ton. So for an average-sized family home in a cool climate, you’ll want about 280 ft cubed.
It’s important to note upfront that you won’t be harvesting your free fuel for about ten years. By taking out the less sturdy trees first, you’ll leave more room for the healthy trees to really thrive. Of course healthy doesn’t have to mean straight: for firewood, it doesn’t matter.
Aside from thinning out your woodland by strategically removing whole trees, you should probably coppice. It’s an excellent way to improve your timber yield, and coppicing is often a much easier skill for you and your labor force to master.
Ash, alder, hazel, oak, sycamore and willow are all well-suited to coppicing. Ash is a favored species because it has a naturally low moisture content, meaning that it’s easier to dry out thoroughly. The best way to learn coppicing is by paying a professional to come out and do it the first two or three times, teaching you as they go. Alternatively, you can volunteer to coppice woodland as part of a farm or wilderness conservation volunteering scheme.