One neat thing about the Melanesia is that it calls for several pieces of found timber, to be used as spars, outrigger poles, outrigger attachment sticks, and the outrigger itself. The plans give detailed specifications, including length, diameter, and, in the case of the outrigger float, ideal density. They go on to recommend certain species of tree that might be good for each purpose, and mention that bamboo is acceptable for most of these applications as well.
Dimensional lumber can be substituted, but it's described as an inferior choice, and I'm on a tight budget anyway, so there's no reason to go that route. I'm tempted by the idea of using bamboo poles because of their incredible strength to weight ratio, which would really maximize the boat's performance. But poles are prohibitively expensive, because they don't seem to be available locally, and only expensive trucking companies will ship parcels as long as 12-13 feet. So found lumber it is.
James states in the Melanesia plans that using found timber will change your relationship to your environment, because you'll suddenly find yourself assessing every tree you pass. I can confirm that this is the case. In the last week, I've noticed dozens of trees along my daily commute that never caught my eye before.
The plans actually list a density figure for the outrigger float (ama) of 30lbs/cu. ft. Not knowing wood densities by heart, I looked it up and found that elm, the most plentiful wood in my back yard, is too heavy. Pine, which is abundant in Colorado, is all over the density table at 23-55lbs/cu. ft. Some varieties are light enough on paper, and a friend has a few dead pines standing on land near his cabin in the mountains that I could have. But I have a theory that our dry climate produces a denser pine than is typical. The growth rings are pretty slim on the pines I've seen; I might find something suitable, but it would take a bit of looking.
We have plenty of cottonwood about, but it's rarely straight, and I think it has all the structural virtues of soggy cardboard. It's an odd, spongy wood, and I don't think it could be used for anything on my boat.
Another common Colorado wood that is well under the maximum density but stronger than cottonwood is our fabled quaking aspen. I happen to have a friend who's been battling a blight in a stand of aspens he owns, and frequently brings chunks of dead aspen over when we host bonfires. I buzzed him, and he has a trunk that would be promising, but it's a little short.
So for the moment, the ama could end up being two pieces of aspen joined together, a pine trunk from the mountains, or a particular elm in my backyard. Unless I find something better. I'm considering calling around to local tree services and see if anyone has a better aspen trunk available.
As for the rest of the pieces, I scored a few small sticks of unknown species for the outrigger attachment role. They're supposed to be about 0.75" and springy; I chanced on a pile of saplings the city had cut near our bike path, and found several decent lengths of the right diameter. There are 12 of those sticks; I have at least 3 or 4 now, possibly more. I stripped the bark off a few of them this evening after work, and they seem perfect for the job.
I have one or possibly two standing elms that could make outrigger poles, and I found a couple pieces in my neighborhood this evening that might make good spars, if they're long enough. Length seems to be the biggest problem. Twelve feet is long, apparently longer than I think, because I keep bringing home sticks that are too short to use anywhere.
And a couple good crotches are required to make the spars. I'm pretty sure I can take them from the elms in our back yard.
I'm sure there will be plenty more to say on the subject of found materials in the days to come. I'll be nervous about it until I see a neat stack of stripped poles against the shed.
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