Posted: 24/07/2013 at 20:31
We had been fighting the green slime of nostoc on our gravel driveway for a number of years with no success. We tried every kind of weed killer and moss killer. We tried copper sulfate, lime, and straight bleach. We tried burning it off. We even resorted to spray paint to try to sufficate it. Nothing worked until....... baking soda. We just got bags of baking soda (bicarbonate of soda) from the local feed store and spread it on the driveway using a drop spreader. We put a heavy coat on because we have no idea of the concentration level needed. Within a week the nostoc turned brown - which from experience we know is the "dead" color. The cripsy black color is just a "waiting to be rehydrated" color. We are going to play with the concentration and see if dissolving the baking soda in water and spraying will have the same effect - but for now we are happy with the results.
Hope this helps someone else. We felt we were fighting a losing battle to the slime!