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I want to plant some trees so that I end up having a negative carbon footprint.

I'm looking for a tree that can be used for carbon sequestration, which is not very tempting for illegal deforesting.

Does such a tree species exist?

NOTE: Initially I was thinking about planting walnut trees, but then I heard that they're exquisite for furniture. I'm sure most trees are great for building fires, though...

Many thanks!

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Gail Taylor's team at the University of Southampton is looking at almost exactly this question. Their primary focus is on fastest-growing bioenery crops, but the answer is going to be pretty much the same as for your question, as carbon sequestration is roughly the same as bioenergy accumulation.

They are concetrating on three species currently: poplar, willow and miscanthus. There are preliminary results already, and further work is going on into, among other things, the genetics behind different growth rates.

Local variants will usually grow fastest in their own locale: so find a poplar or willow variant that's local to you, and grow that.

Much has been talked about miscanthus, and it does look like it should be a good crop; however, at least in the UK, large-scale cultivation of it hasn't really succeeded yet. And you're looking for a tree, and miscanthus is a grass.

If bioenergy has a value in your area, then I'm afraid any fast grower is going to have some commercial value. But in terms of the value of the timber itself, fast growers will have low-density soft wood (horse chestnut is a fast grower, and very soft wood), so that should reduce the temptation for illegal logging.

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As soon as you plant a forest it starts to decay. Initially the growth rate is faster than the decay rate. At some point it reaches equilibrium.

To maximize carbon capture you want to plant something that adds biomass quickly. To keep it sequestered, you need long life.

Your best strategy is to plant fast growth trees for your area, coupled with shade tolerant long lived trees to take over. You are createing your own plant succession.

Possible candidates: (I'm speaking from experience mostly in USDA zone 3, but this is pretty applicable to zone 5. Once you get warmer than that you need to check out your hardy plants.

Fast growth: the entire poplar family grows at some 3-6 feet a year depending on water, and length of growing season. (I get about 3.5 feet per year with Hill Poplar unirrigated, in central Alberta with about 120 frost free days per year.) There are some tree form willows that do well.

On the conifer side, siberian larch and eastern white pine do well.

For your second layer, look at the maples. Most are moderately shade tolerant. Red maple, and sugar maple are fairly long lived and get quite large. If your climate has the right temperature regime in spring, the maples may have good value as a source of sap for making maple syrup.

If white pine grows there, it can become part of your long range plan. Where I grew up in northern Idaho 400 year old 200 foot high pines while not common, weren't exactly rare.

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An unexploited forest has many benefits but carbon sequestration is not an exclusive driver. You can invert the logic and argue that any wood used for making durable things is an additional carbon storage opportunity.

To capture carbon, plant growth must be sustained while preventing burning or decay in the open. Once the growth/decay equilibrium is reached, some clearing will foster growth while the excess carbon is stored in durable products.

Storing carbon means using it for ends other that energy production, or trapping it underground. Any forest zone will either one day be logged for burning or will live until a forest fire does nature's will. Either way, the above ground carbon get's back into the atmosphere.

Making buildings, furniture or other bioproducts for long term use is an other way to store some carbon if that is the goal.

  • In the long run, you either have a forest + furniture, or just a forest. Reducing CO2 means trapping it for good. A forest is an ephemeral state. It doesn't get infinitely big. – Hurelu Feb 18 '15 at 12:37
  • If there is no use for the stored carbon it need to grow on itself until the low layers have no access to oxygen and turn to coal, oil or gas under a sealed rock layer. Making buildings and furniture is just so much easier... – Hurelu Feb 18 '15 at 12:40
  • the next 20 years are going to be crucial for what's going to happen as far as global warming is concerned, afaik. In 20 years, if there's no forest fire... the carbon will stay in the forest – Sustainable Programmer Feb 18 '15 at 12:46
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    Put another way: if there is a choice between 200 years of growing usefull stuff versus 200 years of growing useless stuff. Which will lead to better carbon sequestration? – Hurelu Feb 18 '15 at 12:57
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    Forests store carbon in more than just the (visible parts of) trees. The underground root system is similar in size to what's above ground, and even if the tree is cut, stores carbon for many years. Partially decayed leaves & litter form a layer of duff that can be many feet deep, eventually turning to humus-rich soil. All that represents a sizeable reservoir of sequestered carbon, even though it'd dynamic rather than static storage. – jamesqf Feb 18 '15 at 23:24

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