Let me reintroduce myself - My name is Zeb Haney and I am the founder and president of Tree Resource. I started this company in 2004 to ensure both a safe workplace and an opportunity to practice arboriculture at the highest level I know. I've been an ISA Board Certified Master Arborist® since 2008...
I’ve always found big trees fascinating. The WA state champion Spanish chestnut is located in Tacoma at the intersection of N 27th and Alder. In case you would like to see a local example of this species. ...
The four walls represent active "boundary sites" that work to resist the spread of infection through anatomic, chemical, and physical means:
-Wall 1 resists vertical spread by plugging either vessels or tracheids.
-Walls 2/3 are always in play--resisting the inward spread of infection into the trunk (though these walls will often fail, leading to rapid decay formation).
- Wall 4 brings the vascular cambium back into play--to ultimately compartmentalize the wound in order for the tree to continue growing.