Should I use old water damaged basement floorboards in my Hugelkultur

I’d like to add a whole bunch of water damaged floorboards from the basement in my hugelkultur. The previous owner neglected to fix the drainpipes from the gutters and for many years water has been running through the basement walls and rotted the floor on the one room that has boards.


Here you can see the fieldstone wall that leaks and the damaged boards. As far as I can tell, they’ve never been treated with anything. They could be good source of material for the hugelkultur.

Anyone think of a reason why I should recycle them in this way?

Is there an issue with odd nail remaining? I’ll try and remove as many as possible.

Footnote:

I have permission (from lovely wife) to build a hugelkultur on my front lawn. This is a major coup and I’m super happy. We live on a busy road and have a lovely porch which looks out on traffic. The finished hugelkultur will help reduce the sound of passing cars, filter out some of the pollution, and enable me to get an important gardening straw badge bit. In addition, I intend to plant three deciduous trees along the ridge which will one day help mitigate the summer sun on the front of the house. The road side bank will include “help yourself” berries for pedestrians using the path. These are just some of the reaons - there are a stack more.

The main section will be fifteen feet long, seven foot wide and seven foot deep exceeding badge requirements. The ends will taper in an arc. I have collected out of my neighbours skip / dumpster a whole bunch of logs. They are gnarly pieces that couldn’t be easily split. I also have a couple of overgrown hibiscus “trees” that are growing right next to the house and their roots are growing into my basement through the walls, so alas, they have to come down but will be added. I’d also like to add the boards to make sure there’s plenty of wood material.

It's hard to know what treatments may have been used, though pressure treated wood is generally not used indoors.

Sometimes you can cut an intact piece of pressure treated lumber and look for a ring around the outer edges, indicating how far the treatment has penetrated. After weathering, this test is less reliable.

Even if it's clean, I don't find that milled lumber breaks down or holds water the same way that live tree material does. It may be more useful at the bottom of the hugel. My 2c.

I agree with Douglas’s post ...

But ...I would bet that boards from the basement have been treated. Back in the late 70’s  and early 80s there was a small movement to build basements from treated wood instead of poured concrete or concrete block.  I suspect it was mentioned in some of the old Mother Earths.   Also, I think I remember the University of Illinois conducting a study on it ...but I am not certain.  

Yes, I know the house you are in was unlikely to have been remodeled by Back to the  Landers, but I wouldn’t take the risk.

The road side bank will include “help yourself” berries for pedestrians using the path

"Yes" to the question of using the boards! And, since the hugelkultur bed will be close to a path and erosion can be problematic, how about not burying them entirely and using them on the sides of the hugelkultur bed?
There is a style of retaining hill that inspired much of the property line berm work here that I'd like to share. On a trip to Crater Lake National Park in Oregon, I noticed that the walking paths were constructed with horizontal 2” thick lumber laid out flat, with 2” x 4” spacers between the horizontal boards, arranged like ladders on an angle forming retaining berms along the pathways. Seed-laden soil filled the spaces between the boards and plants grew in these reinforced hills with the wood skeleton slowly breaks down in place while deep rooting grasses and shrubs do their magic of spreading roots and holding soil. The paths in this national park are stunning!
Well, I copied that design using partially rotted, raised-garden-bed lumber. Stacked (no nails needed but I left some old ones in the structure), spaced at an angle, and filled with soil, the wooden armatures coupled with deep rooting plants prevent all erosion into neighboring yards and public paths. Over the 10 years since construction, the retaining wooden forms have become rich soil and the perennial fruits, nuts, grasses, succulents and random annuals are thriving.
Instead of burying the boards, consider building a simple retaining ladder on the path side. There are lots of things to bury in the middle and lower parts of the hill. Those straight boards could serve structural and design functions in this pathway edge application.

P.S. To determine if boards are toxic, "paint" a test board with a slurry made of water and manure or sour milk. If the boards are healthy, moss will grow on them if kept in the shade. If boards are toxic, the microbes in the slurry will die and nothing will grow on them.

Thank you all for your responses.

I’m really liking Amy’s idea of wooden skeleton to stabilise the banks in the early days. This is why I love posting here.

Amy Gardener wrote:To determine if boards are toxic, "paint" a test board with a slurry made of water and manure or sour milk. If the boards are healthy, moss will grow on them if kept in the shade. If boards are toxic, the microbes in the slurry will die and nothing will grow on them.

Great idea and I have a damp corner behind some ferns that is an ideal location for this experiment.

If you opt not to use them for the hugel perhaps because they have been treated, you could turn them into some sort of artwork! A friend of mine did a lot of pallet wood painting. Took two to four pieces of pallet wood cut to about A3 size and painted simple vibrant ocean scenes on them. The weathered wood texture gives a nice canvas.