How long do I have to harvest a tree after it has fallen

Hey there, I’m new to all this business but a tree has fallen (a beautifully enormous...maybe 150-200ft tall Doug fir) down a hill from my house, kinda hard to get too but not horrible..

Anyway, I want to mill it and what not but I’m not sure sure how long I can let it sit there in the forest...

How long can I let the fallen tree sit in the woods? (Wpnw)

I'm not an expert but I'll as a question that will help the experts answer your question better.

Why did the tree fall down?  Did a storm knock it down while it was alive or did it die and fall down later?

Mike Jay wrote:I'm not an expert but I'll as a question that will help the experts answer your question better.

Why did the tree fall down?  Did a storm knock it down while it was alive or did it die and fall down later?

Ah, a storm knocked it down! But I guess I’d like the answer for both those options

Sometimes the further question to ask is "why did the tree fall down?" beyond the storm.  Is there center rot? A dead top (even an old dead spot near the top that has been superceded by a branch gone verticle) is an indication of possible center rot.

Beyond that, generally if the tree has green (live) branches, you have good wood somewhere and it has sap preserving it for a little while. If the tree has a full branch structure and no dead top, that is a good sign

I don't know how long you can let Doug Fir lay on the ground before fungi set in for good.  Depends on how much of the trunk is in ground contact, how many large branches are speared into the ground (wicking moisture upwards into the trunk), the moisture content of the soil, the volume of rain or snow falling on the horizontal surface, and what your evaporation rate is.

Lots of factors can influence a fallen tree's longevity as far as useful lumber wood.  Better to get it out of there, remove the branches, and get air under it, up on some reject logs, and plan to mill it ASAP if you have plans for it.  If you dont have plans to use the lumber right away, you can debark it and roll it periodically to slowly cure it while keeping it off the ground on waste logs.

What little I know for my area is that if a pine tree is standing dead, it will have blue/green streaks in the lumber (cosmetic) and will likely have an ant colony living in it and eating out the center.  

If you're cutting a tree, the better time is in the winter when the sap is down.  Apparently the finished lumber will dry quicker and the uncut logs won't get moldy on the ends as quickly.

Black spruce in my area rot out inside before there is any external appearance of a problem.  A perfectly good looking 60 foot high tree will break off in the wind and the base will be 1/2" of wood surrounding a hollow center.  One did that and hit my house this summer

Long story short, if a conifer is standing dead in my region, it probably isn't good for lumber anymore.  I'm not sure about hardwoods though.

I think it depends on the climate... the moister it is, the quicker rot will set in. If you are in a rain forest zone, I would think it safest to mill it within a year. If you can debark it and keep it off the ground, you may have another year or more, depending on whether you want to market it or use it yourself. I recall reading about a softwood forest killed by a fire or something, which kept being harvested at lower grades for a good number of years.

Species is also an important variable in this calculation; oak or black cherry can lie on the ground for a few years before losing significant usefulness, while birch rots very quickly.


I strongly second all of Roberto's advice.

Birch rots while it's still standing

Yep, if birch falls because it's dead, it is probably already toast... or mulch

Dougls Fir bark is incredibly rot resistant but the wood not so much. Cobville, in the Oregon rainforest, has some bark that's been used in the main walking paths for 15-20 years, sitting in mud, and there is no rot. Of course if the bark isn't protecting the wood beneath then that wood will start to go. Also depends on what the tree is sitting on/in. The less soil contact the better as you know. If you have all bark under the log or it's elevated then you get a lot more time, but I wouldn't want to guess. Months, maybe a year? I don't know that.

Too bad it's not cedar, I was digging wood duff out of a 100 year old douglas fir stump and except for the fat wood (where all the sap accumulated over the decades, great fire starter) the stump was turning to powder, great for compost toilet cover. But the red cedar stump sitting 5-10 feet away, cut at the same time, had no visible rot at all and was hard as a rock. Maybe in 400-500 years the stump will soften up a bit...

Much depends on the tree, and where it lies.

Conifers tend to last longer than leaf trees, due to the pitch.

A tree that is off the ground, either due to rough ground, or supported on branches is good for several times as long as one that is flat to the ground.


My experience here in Alberta:

Standing dead poplar go bad in about 3 years.  The wood is punky.  If you have room for it, cut and store.  The punky wood takes about twice as long to dry, and the chunks are very light.  I call them 'powder puffs' There's not a lot of heat in them, but they smoulder well, and are a nice choice on a cool spring or fall day when you want just a little heat.

Fallen poplar on the ground should be harvested right away.

Birch will rot standing up.  Take them down as soon as you see that more than half of the top is dead.  Birch must be split to dry.  The bark is so waterproof it will rot before it can dry from the ends.

Spruce is good for 5 years dead, as long as it's not flat on the ground.

***

Look for mushrooms.  This is an indicator that it's past it's best before date.  Poplar with bench fungus will be punky.  But check on up the tree.  Often the center at the bottom of the tree fails before the top dies.  I just harvested a 20" poplar 100 feet tall.  Bottom 12 feet was powder puffs.  Rest of it was solid.


You can burn anything if it is dry.  I prefer poplar because it's so much faster to harvest and split than spruce is.   Has only 2/3 the heat, but it takes half the time.

I have a 12 x 30 woodshed partitioned in half.  Each side holds 2 years wood.

If you have the time to  cut off the top and bottom, you may extend the length of time you have to do a better harvest. Those cuts won't take too long and will also help you plan whether the tree is worth worrying about

If you know the lumber length you're looking for, making those cuts would also help start the curing process. I suppose under certain circumstances branches might wick water, but they also prevent ground contact of the full log so I wouldn't bother with them until it comes time to bring it in

How steep is the slope, how far down is the tree. What kind of equipment do you have to get it out.

I'm thinking you have to decide what usable lengths you have there and what lengths you want. If you want 8 foot lengths then can you get an 8 footer up? Maybe if you want 12 footers you could get them out of smaller diameter/lighter logs. Is it snow/slippery soil that's keeping you from getting one out now. Once you get one out then the next one will be no harder and you'll have the experience.

I would say inspect it and see. From my experience, when a tree falls in a storm, it is often started to die before. If up rooted, it's probably solid. If broken off, probably not.

Dylan Gillies wrote:Hey there, I’m new to all this business but a tree has fallen (a beautifully enormous...maybe 150-200ft tall Doug fir) down a hill from my house, kinda hard to get too but not horrible..

Anyway, I want to mill it and what not but I’m not sure sure how long I can let it sit there in the forest...

How long can I let the fallen tree sit in the woods? (Wpnw)

If your tree isn't laying in ground contact (ground that doesn't have mushrooms that come up after a rain) then it will remain as it fell for about 6 months.
If there are any mushrooms around, then the tree will have spores already in it and the longer it lays there the better the chance of fungi decay already starting in the new growth (sap bearing) wood.
For most lumber milling of this sort of tree, you are going to be wanting the heart wood anyway so you must test it by cutting the first length, that will tell you if the wood is still sound enough for your purposes.

Redhawk