A Walnut Tree on the Ground: How Long?
If a down tree sits in a wet area for a while, what are the chances of getting some decent lumber? December 6, 2012
Question
We have some timber land in east Texas, mainly pine, but some hardwood in the bottom land. I found a large walnut on the ground, 30-35 inches at the base and a good 18 foot straight. How long can this tree be on the ground before it starts to rot? I assume it came down in the last six-eight months. We've had a very dry year but this is low soggy land most of the year. I would have to take a Bobcat down to pull it to accessible ground. I've tackled some ash with my Alaskan mill.
Forum Responses
(Sawing and Drying Forum)
From Gene Wengert, forum technical advisor:
It probably has some rot in the sapwood already. The sooner you get it sawn, the better. Use log end coating too.
From contributor X:
I've sawn walnut that had lain in pasture grass five years. The sap was gone and the heart had some checks all along the outside of it, but there was still good wood after the first few inches where the heart was still green. The sap may be punky as Doc says, but it may not either. Eight months is nothing for walnut, especially if it hasn't seen much direct sun. You'll have little to no loss at this point.
From contributor X:
If it's not too far you should do as Doc says and seal the ends. It would be best to also take some tin down there and cover it if it's getting direct sunlight. You don't normally want to cover logs with tarps, but if you can't get tin down there go ahead and cover it with a UV resistant tarp (only if it's getting a lot of sun) but not if it's getting mostly shade. You'll lose the sap pretty quick if you tarp it, but the heartwood will be fine. I like to keep sap in my walnut. It looks prettier for most furniture.
For the record, you would never want to tarp most species for any length of time at all because without air flow you'll get molds. It's not going to hurt the walnut heart though.
From the original questioner:
It's a long way - the root ball is still attached. I have some tin. It’s all sun now and in the spring mostly shade.
From Gene Wengert, forum technical advisor:
Because of the warmth and the high risk of insect damage, prompt milling is essential. Further, as this is on the edge of the range, the color is likely not to be the greatest and it will not improve with age. So, my advice, which I believe is accurate for this situation, is to mill it rather promptly before we see much damage.
From Gene Wengert, forum technical advisor:
Incidentally, several other posters have agreed that end coating in this warm location is very important. The suggestion to end coat is indeed correct and is excellent advice.
From Gene Wengert, forum technical advisor:
Note that a 34" diameter log with 2" of sapwood has about 20% of its volume in sapwood, which is also likely clear and of highest quality initially. As this rots, then heartwood will be lost when the log is sawn with the initial cuts that develop flat faces. So, letting the sapwood rot will cut lumber heartwood volume by around 20%. This loss can be estimated by pi r squared, which has r = 17" or 15".
From contributor X:
I will say Doc that based on my experience I have not seen the level of problems with the heartwood. Although I've milled quite a bit of walnut I don't usually let them lay for long. On at least four or five occasions I have, and the only heart loss was due to the logs laying so long in the sun in the pasture before the grass covered then after a few seasons of the owner not shredding that pasture around them. This wasn't intentional on my part, the logs were a "find". I wouldn't have let them lay that long and for two-three seasons with direct Texas sunlight, there was considerable check. Even still, those are the logs that still had good wood in them. So this instant held true to your caution but it is extreme.
On the other three or four piles I've allowed to lay in the woods and one here in the woodlot for about 18 months, there was no heart loss and most of the logs showed little to no sap rot nor even stain. The longest I allowed walnut logs to lay was three that got "lost" in a heap of castaways for ten seasons, and these logs lost all their sap where they had ground contact and about halfway up the logs. This is the pile that I got a bona fide spalted walnut from - spalt in sound heartwood.
I do agree with you that the best course of action is to mill all logs promptly, but where a situation like the OP cannot do so, I think his log will be fine if he keeps the rain and sun off them especially, and also if he had sealed the ends to prevent checking. By now they have checked quite a bit I'm sure, so there will be a little loss there. My caveat is that this is only based on my experience which compared to yours, is limited.
From Gene Wengert, forum technical advisor:
I think that dry walnut would easily sell for $3 per BF. So, if there is a small loss of 20 BF that is potentially $60 income. For that money, it would be worth avoiding a risk of loss and even spending a few dolalrs to do so.
As much of the best quality lumber comes from the outer portions of the log, and because about 8-12% of a log (from the outside) is lost when squaring the log up forming the faces, and because it would be best to have the waste come from sapwood rather than heartwood, and because east Texas can be dry and warm creating face checks on the log (as well as end checks) and can cause sapwood to rot more quickly than in more northern locations, I do believe that it would make economic sense, conservation sense, and common sense to try to process this log as soon as possible.
Recall the original question was about how long can the log stay before it begins to rot. We added information about other losses if the log is not processed soon.
From the original questioner:
I guess my fear was that everyone would say it'll ruin in no time at all. Even in that case I would be unable to retrieve in a timely manner. I think it might be ok, and I might try to launch a more aggressive expedition.
From Gene Wengert, forum technical advisor:
Losing the sap is indeed an issue. The yield of a 30" log is 675 bf, but if it drops to 28" diameter due to the loss of 1" sapwood (which is conservative as sapwood is likely higher in east Texas) all the way around, the yield drops to 585 bf. That is 90 bf or about 15%. As I already stated, the sapwood on a fresh log is partly lost when the slabs are taken off to square the log. However, if the sapwood is gone, then you will lose clear, high value heartwood as you square the log.
