This is Laminated Root Rot

We have our share of Phellinus (Poria) weirii -- Laminated root rot.

Laminated root rot is the cause of the high percentage of dead fir snags in a few small areas of our property.



This tree fell during the winter and I discovered it in the spring. Notice how small the root wad is, compared to what a healthy blow-down would have. Another tree fell about 50 feet away.

 

Leaning fir trees often indicate weak roots. Butt rot is obvious here: the fir is slowly uprooting and has already lost its top. It's surrounded by fir snags and large living fir trees with weeping trunks.

This is considered to be the most damaging root disease in the Pacific Northwest, as it kills the greatest concentrations of trees in the areas where it is present. Sometimes called butt rot, this disease is most tragic because it kills all Douglas Fir (Pseudotsuga menziesii) in an expanding radius and makes it impossible to grow that species again in that location.

Root rot is most obvious where there is a patch of jack-straw trees, snags and leaning trees. Dead fir saplings among fir snags are a pretty sure sign. Look more closely for weeping tree butts, fading  crowns and firs that fall by uprooting -- particularly if the root wad appears unusually small for the tree.

The disease is spread by root contact between an infected tree and healthy ones. The disease kills susceptible hosts by either predisposing them to windthrow by rotting the major roots, or by destroying their ability to take up water and nutrients. Saplings and small poles are usually killed quickly, while older trees may confine the fungus to a small number of roots or to the butt log and survive for many years.

The fungus may remain viable in stumps for 50 years and thus infect regeneration, although it typically takes 10 to 15 years for roots of the new trees to make contact.

There is no treatment for root rot. The only recourse is to cut all trees of that species in the infected area, and one more tree's width (drip line radius) around the circumference of that area to be sure. Sadly, this sometimes involves clear-cutting a sizable area. Our neighbors just over the ridge did that, although I'm not sure they know it, maybe the logger made that decision for them. The timber generally is merchantable.

If we postpone action, the area only gets larger. In one area we cut about an acre of infected fir trees, but we were able to leave several very tall, healthy Ponderosa pines.

Started Logging for the 2011 Season

My first realization, as I marched into the woods with my saw, tools and safety gear, was that all my skiing over the winter didn't keep me in shape for this. My second realization was that my aim is rusty.

Two weeks ago, we turned our attention to cutting trees from 3.5 acres in the north end of our property. It's been several years since a crew thinned this stand from below, cutting everything under 7 inches dbh and pruning the marked leave trees up 12 feet.

This summer we need to remove about half the remaining trees, predominantly Douglas Fir, mostly from 8 to 20 inches dbh. Our final density will be about 110 trees per acre. At the end of the summer a crew will prune the leave trees up to 16 feet. This is all part of our NRCS EQIP contract.

So last week I donned boots and hardhat, fueled up my Stihl 440 chainsaw, strapped on my tool belt, and climbed through thick brush up a draw. Once I caught my breath, I felled the first couple of trees with no problem. Then they started falling a few degrees off where I wanted them to fall. This led to trees hung in the branches of other trees, which gets complicated. I can't work under that hung tree, lest it suddenly falls of its own accord. We could cut the tree it's hung in, but often there's a blue mark indicating it's a carefully selected leave tree.

The safest way to drop the hung tree is to winch the butt out from under it. We did this with 2 trees the first day. Only 10 trees made it to the ground that day.

This week, with a freshly sharpened chain, I was able to hang more trees more efficiently in less time. Getting frustrated and creative led to another problem: a tee-pee of trees. When I hung the first tree of the day, I saw that I could fell another tree that would hit the hung tree, bringing both to the ground like dominoes. Instead, it hung, too. In my brilliance I added a third tree to the structure. Now it was unsafe to approach within 1/2 mile of this mess.

The only solution was to stop work and get the tractor to winch the trees down. The first two came down easily. As we stood in the woods discussing our strategy for winching the third tree, it came crashing down. It was a close-up reminder that it can happen any time, without warning.