It's almost relevant, because C14 decays into N14 (which is what we measure for carbon dating). N14 on the ground is a stable fertilizer. But if it is airborne

It's almost relevant, because C14 decays into N14 (which is what we measure for carbon dating). N14 on the ground is a stable fertilizer. But if it is airborne and makes it to the planet's uppermost layers, cosmic rays eventually convert it back to C14 again. It's an interesting cycle.