Harvesting bamboo

[Hilongbow]

Aloha,

I have access to a few bamboo stands of unknown variety. I'd like to harvest some for bow backing, and I'm looking for advice.

Does species/variety matter? Should I be looking for greener shoots, or more mature yellow shoots? What is an ideal diameter? Any other advice?

Thanks in advance!

[Eric Krewson]

I have cut a lot of bamboo for backing. Cut stuff 4" or larger on the base diameter, you can use smaller but the bamboo will have a high crown on your bow plus you will be limited to a narrow width for your bow.

Cut your poles 6 or 7 ft long leaving you plenty of room to put the nodes at equal spacing on each bow limb.

Use a long stick, (I use a hoe handle) to knock the internal nodes out so you can get air flow through the trunk for drying, it will take forever to dry with the nodes intact inside. Let the bamboo dry to a tan color before you split or cut it into slats. If you split the trunk green the slats may cup up side to side as it dries and be ruined, better to let it dry in trunk form. You can seal the ends to stop splitting while it dries.

The older shoots you cut the better, they will be tougher and more stable.

[HH~]

What Isle you on Braddah?

Best is to get stuff that is 6" or better yet 8" dia. If you cut green you have to season it and it like seasoning wood, it take time. I like to find the standing dead in your Boo thicket. Cut it it and drag it out if you can because its already seasoned. Get it in the dry time of year but you dont have to. I use to cut a bunch in the Islands. They make a boo splitter. Its a big circle blade with a star blade  in the middle. Cut the boo 80" and you pound this boo cutting wegde/blADE down from the fat end. Had two paddles (if you will) on eacH side so once its in you can keep splitting. Works better on green! Lots of ways to cut it, band saw, batt powered circular saw. I watchED this crazy Braddah cut it on table saw with blade up 3-4" ( not this guy)!.

Hedge~

[Hamish]

I've never had green split bamboo warp sideways. The bamboo farm I get the from will cut green and split them with a bamboo froe, in front of your eyes. Then you shave off the inner nodes with a machete.

I have heard  you must leave them in the round, but then the bamboo splits on its own whilst drying, and you don't have control over how it splits. You also get mold growth in the underside because of trapped moisture.

[gutpile]

I've cut and split boo green and it curled on me.. now I just cut leave full size round ..bust out nodes and put up..when it turns yellow I split it and I don't have any problems.gut

[Eric Krewson]

I have had at least 50% of my split green bamboo cup as it dries, better safe than sorry. It could have been the species which I think was mosa. The last 10 or so poles I cut were mandrake, tougher stuff but after my bad earlier experiences I dry it whole.

Hamish, you have some bad info, bamboo doesn't split on its own or get moldy drying. If you knock the nodes out it forms chimney and has a constant air flow through it.

If you store your trunks in a basement it will mold, been there done that. I use the corner of my shop for storage and drying, Alabama summers take care of the drying process.

I don't split my bamboo, I pop a chalk line on it and run it through the bandsaw, quick and easy. I cut away as much of the belly as I can with a bandsaw, run it through the jointer and finish flattening the belly with a belt sander with a 36 grit belt.



Yep, I have cut a bunch of bamboo, this is the last batch, the patch with up to 8" trunks has been leveled with a bulldozer, dang.

[HH~]

The best boo i harvested was always natural dried stuff. The thickets ran about 60ft tall or more. Its real work to get the dried stuff out. As Eric indicated if your cutting splitting it green wiring it in bundles to 2x2's in a big round bundle will help. In Hawaii I had a large Lanai with a tin roof and had racks store Waiwi and my boo. The thicker then boo walls and larger diameter the better for backing strips.

To add no green air dried seasoned boo I ever used had the snap of standing dead bamboo. Just a huge difference it's snap once glued up. I watched some HAPA guys split it and cut on table saw and it look like death on a stick but they were good at it.

HH~

[Hamish]

Eric, Smashing out the inner nodes will go a long way to stopping mold on the interior, so that's a good idea if you want to leave the pole in the round.
I have seen plenty of poles that develop cracks from drying(they had the inner nodes intact). With several splits at different alignments around the pole at different points along the length makes it very hard not to get waste strips that are unusable for backings.

As with straight wood that has been split it won't twist when drying(it might develop reflex though). (an exception is straight, small diameter saplings which can corkscrew if split when green).

I leave my green splits laying flat on a shelf, not propped up vertically against a wall where they could potentially dry bent or twisted under their own weight.

[Hilongbow]

Thanks everyone for the info. I think the trunks are in the 4"-6" range. So no concern about variety?

Hedge, I'm on Big Island. I'll look for some dead standing but given our 140"+ of rain per year (over 40" in the last 4 weeks and no end in sight) I'm not too hopeful that it'll be in good shape. Maybe if it hasn't been dead too long the waterproof outer layer will still be intact.

[HH~]

Sure, the rind keep it dry. No worries thats why it takes so ling to rot. Green or yellow will work as for varieties. You look in that thicket , it grows to maturity and dies out just like grass does. YouR standing dead you have to cut rather than split.
 
Spent plenty time on big island. Had an office and a couple guys who worked for me at the Hilo Armory.

HH~

[Eric Krewson]

I did an experiment a couple of cuttings ago and left a piece under my deck with the inner nodes intact during the summer, I knocked the nodes out of the rest. Long after the stuff that had the nodes knocked out had dried to tan the piece under my deck was still mostly green, bamboo just won't dry well intact, it will over time. When I knocked the nodes out of the test piece there was still water trapped between the nodes.

The bamboo in the picture above was some I pulled out of a burn pile after the bulldozer flattened the patch. It had been laying on top of the pile in the summer sun for a few months but was mostly green except for the side facing up. There were no cracks in the trunks of this bamboo in spite of it being exposed out in the weather. Again, I believe the species made it a tough customer, it was Giant Timber Bamboo or mandrake. As soon as I knocked the nodes out it dried to a nice even tan and was sound and solid.

[gutpile]

never had boo naturally dry into reflex... deflex yes .. gut

[Eric Krewson]

If you take your first finger and put it about 1" from your thumb, that is what a some of my dead flat slats looked like after they cupped, this is side to side not end to end.