what does excellent wood quality mean?

Other things that involve bamboo

Moderator: needmore

Post Reply
Eric
Posts: 32
Joined: Sat May 02, 2015 11:27 am
Location info: 0
Location: NC zone 7

what does excellent wood quality mean?

Post by Eric »

I'd like to understand more about the differences in the wood quality of different Phyllostachys species. I see some like P. bambusoides billed as having excellent wood quality, but then I see it noted as having only medium thick walls. Does that mean the wood is useful particularly for splitting but that it's not so outstanding for using as whole canes? Which species produce the strongest whole canes? Are the strongest always the thickest? How thick are the thickest? How thick are the culm walls of moso, for example? I'd be interested in anything else anyone cares to share or link to that explains what wood quality really means.
Thanks!
Eric
zxylene
Posts: 195
Joined: Sun Jul 26, 2009 4:48 am
Location info: 0
Location: Landisburg,PA USDA zone 6b
Contact:

Re: what does excellent wood quality mean?

Post by zxylene »

Some sort of chart with type of boo and then usage type boards, structure (whole poles) etc would be great. I dont have anyinfo on the but will need it in a few years after most of my boos have matured and I am ready to build my kids play house out of boo. I do know from experience that when you harvest (how old the culms is) and what you do with the poles after said harvest (keep branches on and sit base in water) greatly changes the risk of cracks and overall strength.
User avatar
David
Posts: 1495
Joined: Fri Jan 13, 2006 6:42 pm
Location info: 30
Location: Middle Tennessee (Murfreesboro) USDA Zone 6b/7a Record low Jan 1966 -14*F Frost free April 21-Oct.21
Contact:

Re: what does excellent wood quality mean?

Post by David »

I began collecting culms early this spring to get a subjective, but not very scientific , understanding of bamboo wood quality. My interest is in flexibility, and returning to its original shape after bending, because I want to use the wood for bow backing.

I collected 1.25-1.75" 4+ year old culms of angusta, lithophila, praecox, vivax, yellow groove, viridis, Robert Young, and parvifolia and took them to my shop to dry a bit. The first discovery was that wall thickness and bending resilience dropped off rapidly at the point where the branches began, so I limited my collection of poles to the un-branched lower segments. This may explain why culms broke this winter under ice loads at or near where the branches began, but I'm not sure so you can make your own observations.

For my purposes lithophila, viridis, and parvifolia were the most flexible and returned to their original shape after bending. Lithophila was the most flexible followed by parvifolia then viridis. Vivax and yellow groove snapped like twigs which is no big surprise.

Standing as a column all the bamboo were exceptionally strong and all supported my 185 lbs. In building a structure one would consider lateral loads such as wind, and the height of the structure. Scaffolding is built with long overlapping ends, and is lashed together. I have seen a picture of bamboo scaffolding, and steel scaffolding after a typhoon and the steel was wrecked while the bamboo was still standing. I wish I could find that picture again maybe someone can find it and post it here.

Moso is used for flooring because it has thick walls and is hard, and wears well. You will notice that bamboo flooring is all laminated from squared up .5 - .75" strips.

Bamboo baskets are made with thin walled bamboo strips, so vivax could be considered to be a quality bamboo wood for basket making, but would be useless for flooring.

I think bamboo wood quality has everything to do what ones intended use or application is for the bamboo.

I searched scribd.com for "building with bamboo" and found dozens of documents in the public domain regarding strength, building techiques, bamboo structures, and just about anything one could think of regarding building with bamboo. Scirbd.com is a subscription service, but they offer a free trial, and you can download all the free public domain books, articles , documents, research papers, etc. that you want. I've happily used it for several years.
David Arnold
Middle Tennessee Bamboo Farm
USDA zone 6b
Post Reply