There has been a number of 'Char' threads that have addressed the possible phenomenon that makes Terra Preta the extraordinary thing that it appears to be. Activated Charcoal and Innoculated Charcoal are important concepts to keep in mind. The problem of "Dog Spots" may very well be addressed under the heading of - "Activated Charcoal". If we think of Char as an empty sponge that is capable of holding many times it weight in water or other substance - We can envision it as sucking the water/nutrients out of the surrounding soil until it is 'filled'... We would expect that a 'raw' mulch on the surface of our garden,(Wood chips , etc.) would use the nutrients in soil, to degrade the the mulch - thus - 'tying up the nutirents' and depleting the amount of N available to the existing plants... is commom knowledge... Activated Charcoal is capable of absorbing or 'adsorbing' elements as they occur nearby... So the question is... ... : Could raw Char possibly adsorb enough of the dog urine urea to prevent it from killing the spots on which it was dribbled??? Any ideas???