Heating with Wood & the Environment: Part 2 – Choose Environmentally Friendly Firewood
In this article we continue in our series discussing how you can heat your home with wood in a more environmentally friendly way. In our last article, we described the environment impacts of burning wood. In this article, we discuss how selecting the right wood can reduce those environmental impacts. Basically, before you select the wood you’ll throw in your stove or fireplace, you want to consider two things – what you burn and where it comes from.
What Type of Firewood is Best for the Environment?
The best burn for the environment boils down to some very simple math: Best burn = Maximum heat per unit burned + minimum harmful emissions. Thus, you want firewood that burns efficiently, produces minimum smoke, and has no harmful substances. Fortunately, efficiency and smoke are related – generally, the more smoke, the less efficiently the fuel is being burned.
First, you want “seasoned” (or “cured”) firewood – firewood that has been left to dry for some time. Burning unseasoned firewood is probably the most common mistake people make. Wet firewood burns very inefficiently and produces lots of smoke to pour out of your chimney. Ideally, properly seasoned firewood has less than 20% moisture content. It typically takes a good 6 months of being left to dry in a well circulated stack to for wood to become adequately seasoned. Also, hard woods like oak take longer to dry out than soft woods. Adequately seasoned firewood will weigh 50% to 75% less than fresh, “green” wood. Some other indications that the wood is properly seasoned include: grayed, discolored wood; bark that is falling off; cracks and splits; and being dry to the touch.
Species of Wood
The next thing to consider is the species of wood. Some species burn more than twice as efficiently as others. Some species naturally produce more smoke. Finally, some species are easier to split and start a fire with. Sometimes, you can find wood that is efficient and easy to work worth; other times you may need to combine long-burning woods Hickory, Beech, and the plentiful White Oak are three excellent species of firewood you might find in the Washington DC region. For more details on firewood species, go to the State of Maryland’s page on Buying Firewood; they have excellent charts, and we highly recommend referencing this page before selecting your firewood.
Harmful Substances in Wood
Not all wood makes for safe firewood. If wood has not been stored in a properly ventilated stack, it could get moldy, and mold is typically something you want to avoid breathing in any form. Chemicals are an even more serious hazard. Do not burn painted or stained wood, plywood, particle board, or any wood product that has been treated with chemicals. Pallets, for example, are often treated with chemicals like flame retardants and pesticides that contain toxins such as arsenic and formaldehyde. Is this the kind of thing you’d want to breathe in? Neither do your neighbors.
Where you get your Firewood Matters
Now that we’ve covered what types of firewood are best for the environment, we’ll explain where to source environmentally friendly wood.
As we discussed in our last article, deforestation is a major environmental problem that affects us all. Deforestation is where large pieces of forests are cut down and the trees are never replaced. Forests are home to millions of species; additionally, reductions in the number of the Earth’s trees are contributing to the greenhouse effect. Thus, it helps us all out when you choose to consume responsibly harvested wood over deforested wood. Responsible sources of firewood include sustainable logging, sustainable plantations, agroforestry, and waste wood such as deadfall, debris, and recycled pellets.
The Proximity Issue
It is always better for the environment to burn firewood near its origin. The fewer miles the wood travels, the less gasoline used, and the better the carbon footprint. In addition, some trees may be diseased or infested with pests, and you could introduce these tree killers to new areas when you move wood a long distance. Because of this issue, there are frequently restrictions and “quarantines” on firewood movement in many states – you can look your state up here. In Virginia and Maryland, for example, there have been restrictions and recent quarantines because of Emerald Ash Borer infestations. This troublesome Asian beetle is thought to have been introduced to the country in 2002 and to the DC area in 2007, and has utterly decimated local populations of Ash trees.
The best sources of firewood, ecologically speaking, is waste wood; the wood has already fallen or been felled – you will just happen to burn it instead of letting it decay. There are several ways to obtain waste wood.
First, if you have the capabilities to remove the wood yourself, you can ask around town to see if anyone has wood they need removed. Your neighbors may have free wood in the form of stumps, fallen trees, limps, and branches just laying around on their property. You might be able to do them a favor, and get free eco-friendly firewood in the process. Just be sure to ask them first – assuming wood is free for the taking could bring you some problems!
Another way of obtaining waste wood is to ask a professional give you theirs. Landscapers and tree care professionals often have an overabundance of wood. If you pass one at work next to a pile of freshly felled limbs, you may be doing them a favor by seeing if they would like help taking some of it off their hands. Occasionally, a friendly tree professional will even drop off the wood for you if you aren’t out of the way.
Also, keep your eyes peeled for waste wood when driving. Sometimes, firewood appears on the curb – keep your eyes peeled when you’re driving for piles of wood on the side of the road with a “free wood” sign – it happens!
A final way of obtaining free waste wood is by scanning internet classifieds. There is almost always free wood posted on DC’s Craigslist, for example.
Wood pellets and wood brick are also often made of waste wood that has been recycled into great burning wood. Just remember that pellets are for pellet stoves, not your average fireplace. Many wood bricks, on the other hand, work great in standard fireplaces. Many dealers provide pellets and bricks.
Just remember the following in regards to waste wood: always properly season firewood; make sure it is not ridden with mold, chemicals, or pests like termites or ash borers; and do not move the wood long distances. We also advise familiarizing yourself with local ordinances if you plan on heavily utilizing waste wood.
It’s often easier to buy your firewood. When doing so, you want to make sure you get good firewood sourced responsibly. Anybody can have leftover wood and claim to be a firewood dealer, and many don’t know or care what they sell or where it came from, so you should use a reputable dealer.
Most states have regulations on firewood sales, and many states, including Maryland, require firewood dealers to have a license. To find or verify authorized dealers in Maryland, go to http://www.dnr.state.md.us/forests/fpo_search.asp.
Anytime you burn fuel, there is an environmental impact. So remember – what you burn matters!
For more on Wood Heat and the Environment, read:
Part 3: Burning a More Responsible Fire
Part 4: Environmental Comparison of Wood Burning Stoves & Appliances
Part 5: 7 Ways to Reduce your Chimney & Fireplace Pollution