Raised beds/hugelkultur with cottonwood logs

I have quite a bit of cottonwood logs from a small stand (about half a dozen) that had to be taken out back in the summer.  The logs (some upwards of 60' long and up to 30" diameter) have been down long enough that I'm pretty sure they're dead and won't sprout new growth anymore.  I tried giving the logs away and literally nobody would come and get them since they're no good for firewood or other economic activity.

Anyway, we're looking at disposing of them by using them to make some raised beds.  Both for the border and to partly fill the interior.  As long they're not able to spout new growth anymore is there any reason not to use the cottonwood logs?  I know it should rot considerably faster than other woods, and I'm wondering if that's a feature or a bug for this kind of use.

Not sure yet what food we'd grow in the raised beds, but if the presence of the cottonwood would alter the soil chemistry enough to make it more/less suitable to certain veggies please let me know.

Cottonwood is one of the few woods that adds acidity to soil. I can't remember the reference but it made it to my mind palace.

Its likely a minimal change. I would use it with no concern.

My raised beds are filled with cottonwood and birch and did very well last year (their first year).  I grew millet, squash, cucumbers, peppers, ground cherries, strawberries, watermelon, and various herbs, and none of them seemed bothered by anything about the wood I used.  I didn't water the millet and watermelon bed once.  The rest of the plants started to need some watering after about 2 months of no rain, peppers the most.  I didn't even have the beds fully built until late spring so I suspect a whole winter of snow sitting on them will make for a better year this year as far as watering goes.

I plan on adding another layer to my beds if they sink too much, so I'm not concerned if the wood rots quickly.

Wayne mentioned acidity.  My soil is acidic to begin (as low as 5.2 in some areas) with so if the cottonwood adds to that, I think I'll notice an effect.  First year, no problems.

Jan White wrote:Wayne mentioned acidity.  My soil is acidic to begin (as low as 5.2 in some areas) with so if the cottonwood adds to that, I think I'll notice an effect.  First year, no problems.

Hmmm.  I have no clue what the pH of my soil is.  Though, any amendments will alter that too.  I know the soil type is quite variable depending on the part of the yard I'm digging in.  Some is pretty much clay, some is pretty basically good topsoil from having been forest floor for decades at least.

Andrew Mayflower wrote:

Jan White wrote:Wayne mentioned acidity.  My soil is acidic to begin (as low as 5.2 in some areas) with so if the cottonwood adds to that, I think I'll notice an effect.  First year, no problems.

Hmmm.  I have no clue what the pH of my soil is.  Though, any amendments will alter that too.  I know the soil type is quite variable depending on the part of the yard I'm digging in.  Some is pretty much clay, some is pretty basically good topsoil from having been forest floor for decades at least.

I wouldn't worry about it then.  But I'm super lazy.

I tested my soil because the first year I was here was a brutal failure.  I vastly overestimated the life-giving capabilities of my soil (I cringe a bit even calling it soil), despite noting the vast swaths of bare dirt punctuated by the occasional stunted Oregon grape or kinnikinnick bush.  I bet you'll be fine.

Not totally sure what all SWMBO wants to grow, but personally, I'm most interested in herbs and spices to start with.  So, thyme, rosemary, oregano, sage, etc. as well as paprika and cayenne peppers, maybe some other Mexican chilies if they'll even work as far north as I am, also garlic, and so on.  Onions would be nice.  Mostly I want things I use a ton of in cooking.  Eventually bell peppers, cucumbers, broccoli, and so on.

In the past we've grown sugar snap peas, lettuces, and squash/pumpkins.  Plus we have a lot of raspberries and strawberries already established in other parts of the yard.

I would totally use them.  Its soft wood so it'll break down quickly and help produce a lot of soil organic matter.

If your soil has any amount of clay in it, it's most likely alkaline.  I wouldn't worry about acidity.  The wood will create a perfect habitat for fungi, and fungi help mitigate PH concerns.