Aspen cordwood - is this wood good for cordwood masonry walls?

Here are a few pictures of our aspen. Which of these would you say is usable for cordwood masonry walls? Note that many times, these discolorations "develop" and get darker for several minutes after we make the cut. Does the sugar in aspen oxidize, and that's what's causing this?

These are pictures of logs with no overtly rotten areas - just these discolorations and marks. Also, there is no discernible difference in texture in any of these logs as you'd see with rot where the cellulose is breaking down.
Your advice is greatly appreciated.

They are all suitable for firewood. Aspen burns quickly, so good for a rocket mass heater, probably not so good for a stove where you want the wood to last a while.

This wood  tends to be very wet when cut, so if you're doing it on your own land, it might be wise to cut it and split it right there in the bush, then retrieve it when it weighs half as much, by midsummer. When split immediately, the bark will often pop off. This bark tends to burn smokey, so best to leave it in the bush.

Dale Hodgins wrote:They are all suitable for firewood. Aspen burns quickly, so good for a rocket mass heater, probably not so good for a stove where you want the wood to last a while.

This wood  tends to be very wet when cut, so if you're doing it on your own land, it might be wise to cut it and split it right there in the bush, then retrieve it when it weighs half as much, by midsummer. When split immediately, the bark will often pop off. This bark tends to burn smokey, so best to leave it in the bush.

Ah, I should have been more specific. I'm wondering if it would be good for cordwood masonry.

I didn't realize we were in that section. Aspen is one of the most likely woods to rot. It is often started rotting before being cut. I would never use any of it for that purpose. Just about any evergreen would be more suitable.

This has always been a quandary for me. I always hear folks say it is soft and rots quickly.  I have 10 acres covered with aspen, I have beaver dams made of aspen and willow that are at least 30 years old, as that is when the neighbors trapped out the beaver in our valley. The aspen logs are still in place solid and sticking out of the dirt. The only time I see aspen rot is when the ants have burrowed into it or if the heart of an old standing dead tree has gone bad. The aspen in my three year old hugel is still hard and doesn't seem to have fallen apart yet. So in my experience aspen lasts longer than any of the conifers that I have seen. The only way to find out for sure I guess would be to try it on a small shed or dog house or something and see what happens. I have been meaning to build a small Hogan out of some of my aspen logs to put it to the test.

I guess I should have been even MORE specific. LOL My bad!

I'm not looking to find out whether aspen is suitable for cordwood - I know that it is and it is used almost exclusively for cordwood masonry structures in Canada, simply because of it's prevalence.

What I am looking for is advice from people who know the look of aspen and can tell me, in relation to these particular logs potential use in cordwood masonry, if any of these look to be unsound for that use.

Thank you, and I'm sorry for the confusion!

If you're still wondering, in one of his books, Rob Roy says the dark colour on the aspen or poplar, doesn't affect the outcome. Once the wall is complete the black can be sanded down to the fresh wood and the black will not return.

Those all look sound to me. I like to use the "hammer" tests, hit the ends in suspected areas with a hammer, you will notice a sound change if there is a not sound spot, worst case, the hammer head will sink in.

Redhawk

I always hear folks say it is soft and rots quickly.  I have 10 acres covered with aspen, I have beaver dams made of aspen and willow that are at least 30 years old, as that is when the neighbors trapped out the beaver in our valley. The aspen logs are still in place solid and sticking out of the dirt.

 Aspen and cottonwood were used for well casings and barn floors because they have the ability to not rot if they are consistently moist.  That is always the case, but only if they are not already fungally innoculated.  The primary factor in the decomposition of aspen is fungi.  The second factor is making it wet and then dry, and then wet again, alternating it into a fungal rot.  Aspen, although not the best building material, can be quite adequate if, as in any cordwood structure, you provide a good roof line and a good dry foundation area <-these factors, and using split wood that has been dried adequately off the ground and under cover (these two factors eliminate much fungi worry), are going to make or break your deal with aspen.

Dale Hodgins wrote:I didn't realize we were in that section. Aspen is one of the most likely woods to rot. It is often started rotting before being cut. I would never use any of it for that purpose. Just about any evergreen would be more suitable.

OP already redirected the question, but just for posterity's sake, Rob Roy, who I think can be considered an expert in cordwood masonary, highly recommends Aspen for cordwood. You can see him do so repeatedly on this page: http://www.greenhomebuilding.com/QandA/cordwood/wood.htm

There's also a very good article that explains why the concern for rot in cordwood masonary is for the most part unfounded if a few very simple precautions are taken.

https://accidentalhippies.com/2017/01/08/cordwood-rot/

From the Rob Roy page that Jeremy just posted:  A question from a client and Rob Roy's answer:  

Q: Would you recommend Birch as a suitable wood for building a cordwood home? We live in Edmonton Alberta and this seems to be a common wood found in this area. There also is Poplar in abundance here as well. Recommendations?

A: Of two species or wood you have available - birch and poplar (which I assume from your Alberta location is quaking aspen and not tulip poplar) - I would consider the poplar to be the much better choice, because it is more stable (less shrinkage and expansion) and has a much higher R-value per inch of thickness. Poplar was used commonly in Manitoba as log-ends in "stackwall" houses in the 20s and 30s and many of these buildings are still in use today. Birch will not rot, providing the bark is removed, but it is subject to expansion and severe shrinkage problems. And it is a poor insulation. Of course, you should debark the poplar as well (easiest to do when the sap is rising in the spring). If your building schedule will allow it, it is good to dry the poplar at log-end length for a year. If you absolutely must use birch, bark it and don't over dry it, as nasty expansion (a structural problem) can occur. It'll probably shrink a lot, but at least that problem can be attended to a year or two after the house is completed. Oh, and one last thing: Dry the poplar in single ranks with the top of the cordwood covered but not the sides. Let the pile breathe, otherwise fungi are inclined to begin digesting your wood. Ventilation is the best preservative we have.