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What kind of wood should I burn?
- It does not matter what kind of wood you burn: as long as it is really, truly seasoned. In the case of hardwoods, especially oak, they must be seasoned for over one full year! That means last year's wood - NOT this years wood! If you're wondering about which wood is really the best, or which wood causes the least creosote to build up, the answer is the same! Properly seasoned wood produces the most heat, and produces the least creosote! It's not the kind of wood you burn that makes the difference, but whether or not the wood is seasoned. Firewood that hasn't been split for over a year isn't worth a darn! On the other hand, dry well seasoned wood is just great! Seasoned wood produces a lot of heat, and it burns clean!
- If you have trouble starting your fire, or if you have trouble keeping your fire going, you are probably using this years wood - which means that it's not seasoned. Unseasoned, or green wood, is extremely frustrating and disappointing. If wood is not properly seasoned it will be hard to light. It will keep going out. It will smolder. It won't put out heat. It just burns poorly and inefficiently. It is precisely the moisture in wood which causes creosote to build up at an accelerated rate. One fresh-cut cord of oak may contain enough water to nearly fill six, 55 gallon drums. The moisture content in the wood determines how much heat the fire puts out, and how much creosote will build up in your chimney.
- If you are going spend hundreds of dollars on firewood, it's essential to KNOW that the wood you are buying REALLY IS seasoned! Seasoned wood may look darker, or gray compared to green wood - but if you split a piece of seasoned wood - it's WHITE on the inside. It's very brittle, or gnarly. If it is split in quarters, it has cracks running through each piece, and a lot of little cracks on the inner rings. Tap the wood with a key or coin. Seasoned wood gives a sharp, resonant sound, like a baseball bat. Unseasoned wood sounds dull. Unseasoned wood has very few cracks, and it has a wet, fresh looking center, with lighter (“drier looking”) wood near the edges or ends which have been exposed since cutting. When firewood is very fresh, the bark will be tightly attached. Avoid these hassles at all costs! When you get cold, you'll be miserable if your firewood does not produce the heat you need. Only well seasoned wood produces pleasant, trouble free heat.
- Depending upon when it was cut down, softwoods like fir or pine might be dry enough in just one year to burn nicely. But, a year is not enough for hardwoods: especially oak! As far as quality is concerned, madrone is unquestionably the best wood! Madrone is very dense, HARD wood. It burns extremely HOT, and it burns for a long time. Next, come live oak, black oak, eucalyptus, walnut. Tan bark oak and white oak come in last*. A mix of true oak AND madrone is your best bet. *Tannoak, or tan bark oak, is not really oak: it is beech. It is often sold as "tan oak" in quantities by big outlets, but it produces a lot of ash. White oak can be very troublesome wood - if it's not seasoned for a couple of years.
- Fir is probably the most trouble free wood you can buy overall. But, if you read further down you'll see it's advantages and disadvantages. Eucalyptus can be a little gnarly to handle: but is absolutely great firewood. The oak that really burns good, is the very same wood that makes good furniture. If distributors are selling large quantities of wood, it may be because they can't sell it for other useful purposes. Most importantly, stay away from large quantities green wood -- and DON'T be fooled by claims of "seasoned fire wood." Seasoned wood is WHITE inside when it is split. Seasoned wood is comparatively lighter by weight, and so it has a brittle and hollow sound if you scrape an end with your fingernail. The darker color, the cracking pieces, and the cracks on the inner rings are unmistakable signs of seasoned wood.
- DO NOT cover your wood with a tarp .... or you will prohibit evaporation! Use a shed, or buy a prefab wood crib.
- What REALLY causes creosote to build up? Creosote is the condensation of unburned, flammable particulates present in the exhausting flue gas (smoke). The actual cause of creosote condensation, is the surface temperature of the flue in which the flue gas comes in contact. Like hot breath on a cold mirror, if the surface temperature of the flue is cool, it will cause the vaporized carbon particles in the flue gas (smoke) to solidify. This condensation is creosote build-up. If the wood you are using is rain logged, or green, the fire will tend to smolder. Wet wood causes the whole system to be cool, and inefficient. But, dry wood means a hot fire! A hot fire means a hot flue, and a hot flue means much less creosote.
- Back in the early 1980's, tests were conducted to discover which kind of wood created the most creosote in a regular "open" fireplace. The results were surprising. Contrary to popular opinion, the hardwood's, like oak and madrone, created MORE creosote than the softwoods, like fir and pine. The reason for this, is that if the softwoods are dry, they create a hotter, more intense fire. The draft created by the hotter fire moves the air up the chimney faster! Because it is moving faster, the flue gas does not have as much time to condense as creosote inside the chimney. Also, because the flue gas is hotter: it does not cool down to the condensation point as quickly. On the contrary, the dense hardwood's tend to smolder more, so their flue gas temperature is cooler. Thus, more creosote is able to condense on the surface of the flue. So, saying that "fir builds up more creosote than oak" just isn't true! It is a misunderstanding to think that it's the pitch in wood which causes creosote. It's not the pitch that is the problem, it's the water IN the pitch. Once the water in the wood has evaporated, that pitch becomes high octane fuel! When dry, softwoods burn extremely hot!
- Which kind of wood is better? That depends on what you want. If you are a first time fire-burner, or if you only want to burn a couple dozen fires a year: go with a DRY softwood, like fir. Your odds for being happy are higher with fir, especially if you are just now buying wood for this year. The fresh aroma of fir creates a lovely holiday ambiance! Fir seasons quickly, and when it is dry it is truly delightful, trouble free wood! It's easy to get going. It smells great. It's easy to split for kindling. It creates BIG, friendly, luxurious fires! But, it burns much faster than oak or madrone. You must feed a stove more frequently to keep it going with fir, and there is no guarantee that there will still be live hot coals in the morning. It tends to crackle, pop, and throw more sparks than hardwoods - which can be annoying to some fire burners. Also, it is important to know that fir and other softwoods go bad after 4 or 5 years. If fir is allowed to age for more than 4 years, the creosote - which is the flammable substances of the wood - evaporates. While fir is great for hot crackling fires in it's the first few years after being cut, if it is allowed to sit for too many years it goes dead. A deal on fir which seems "to good to be true" - might indicate that the fir is so old that it is no longer really good wood. This can happen with ANY wood that is allowed to age too long. So to be safe in the later part of the season: fir is a good bet. But, for the serious fire-burner: cord for cord the hardwood's may be a better deal.
- Hardwood's, like madrone, live oak, black oak, eucalyptus, and walnut are the definite choice of the serious fire burner. You may pay $350 for a cord of seasoned oak, and only $250 for a cord of fir. BUT, because the oak is more dense, it weighs much more than the fir. You actually get more for your money with hardwood. In fact, you may get almost twice the fire for the money! Because hardwoods are denser, they provide more available fuel in the same space. So, hardwoods burn longer. If hardwoods are properly seasoned, they do burn very, very hot. (Look for oak mixed with madrone.) The fuel available in hardwood enables stoves or inserts to sustain higher temperatures for significantly longer periods. Also, unless the stove is shut down tight, hardwoods may keep a hot live coal bed for days. So as a rule, airtight stoves, or inserts, perform best with dry hardwoods. It is, however, always important to have a large supply of really good kindling - because hardwood can be difficult to start. Having a quantity of fir on hand is great source of good kindling.
- When buying firewood, remember that first and foremost, it must be properly seasoned. The best way to get seasoned wood is to buy THIS years wood for NEXT year! Don't be scared by "green oak." Green oak is the buy this year, for trouble free use next year. A scrupulous first time wood buyer may find a moisture tester to be a good investment. Wood sellers will often tell you that even though this wood was split this year, it will be just fine. Except in the cases of fir or pine, that is not true. Look for gray, or darker, brittle wood that has a lot of cracks in the inner rings. Seasoned wood might look gray, or dark or dingy because it has been sitting sitting in the sun, drying, and collecting dust for a while. But, if you split it: it's dry and very WHITE inside! Unseasoned wood has the fresh clean look of new lumber at a building supply store. Unseasoned wood has that same fresh look on the INSIDE when it's split. Though the older, seasoned wood is darker on the outside, it's bone white on the inside - which means it's really seasoned.
Remember, when wood gets over 4-5 years old, it does start to deteriorate, so the best wood is 2-3 years seasoned. If you find good dry wood of any kind, you will really enjoy your fireplace! But, if you get stuck with green wood, you will be one very frustrated wood burner. Most wood for sale is "this years" wood. If you get serious about wood burning, you must always think one full year ahead! You should always buy this years wood for for NEXT year. Good buys of seasoned wood do come along, but they are often not advertised, because the serious wood burners already know where to go. If you are a first time wood burner, either buy dry, split fir, or hunt down really dry, cracking hardwood. You won't be sorry if you spend a little more money - just to make sure that you get trouble free firewood.
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