I've always been interested in taking the superstition and mystery out of the cultivation of CPs. In the past I've had the opportunity to do so from a cultivation angle, now I have more-quantitative tools available.
I'll often see discussions of old media coming up. Many repot religiously to avoid problems associated with nitrogen buildup in their soil. Many blame nitrogen buildup for poor performance of their plants or the plants of another grower. We've heard about N accumulation from a worm in the media, undrained pots, bad water -- you name it, we've heard it.
I currently find myself in a position where I will be for the next foreseeable future be running soil samples for their total carbon and nitrogen levels. In the process of doing so I need what are called "dummies." These are samples which are used as an instrument check at the start of a run so make sure that it is functioning correctly and not drifting. For these dummies I can run whatever soils I'd like. If I can save my samples for analysis rather than being run as dummies, that's great. If I find a soil which is very homogenous and gives me really consistent numbers, that's super great. I need to run these dummies anyway, so no additional resources would be spent running these samples (lest anyone reading this think I'm essentially stealing from work).
So I'd like to simply poll you for now: If any of you have old CP media (no fertilized soil please!) that you think may have accumulated N over time, would you be interested in finding out how much nitrogen is actually in those soils? I suspect that the problem is often not N buildup, but I'd certainly like to quantify it.
Notes: This would be analysis for total nitrogen and would not provide us information on which nitrogen species are present (that would cost cash and I'd probably need to buy instrument time and reagents, so I'm not really looking into that at the moment). I'll need to do some reading on how well bulk soil N corresponds with available N for peat. I'd need the samples to be largely free of roots. I'd only need a few tablespoons to be able to run the soils many times. These would be run on an as-needed (by me) basis with no guarantee that they will ever be run.
Let me know if you're interested or have any questions.