The best idea for soaking pet urine from the cracks in the wooden floor is to sprinkle baking soda on the boards where needed. Leave it for an hour or two and you will actually see the urine sucked up like a straw. You must repeat this a few times.
By Susan
Susan, I have two chihuahuas and a cat. Most of my home has hardwood floors. Pet urine leaves black stains on hardwood if left for even a very short time. Due to lots of cleaning, my floors have little of the waterproof seal left on them. Although trained, my pets would overshoot the puppy pads, or refuse to go outside during inclement weather. Somewhere I had heard that baking soda might be effective at lessening stains. The trick is to clean and dry the wet area, once discovered, then put dry soda down afterwards. It is amazing how effective it is at stopping stains from darkening. I think that it isn't a good idea to actually use it wet, it seems to remove moisture and neutralize compounds in the urine. Its pretty amazing, easy to sweep up dry, and no odor remains after use.