Acorn Stains on the Driveway - what to do?
 

Seems like a petty thing to worry about with the present state of the world and my Targa having pre-NEcancer but we have a Oak tree in the front yard - great beast that is very fruitful. I don't want to cut it down. The acorns leave a black stain on the drive. Looks like arse. I also live across the street from a fish stocked pond that gets run-off. Using soaps or acids might hurt the Cat and Brill. Any ideas?

Re: Acorn Stains on the Driveway - what to do?
 

Arrange the acorns into a Porsche Logo? :D

http://www.pelicanparts.com/support/smileys/dom.gif

available at Lowes?

Have you tried simple pressure washing?

Don't get a wimpy electric. Get a Real one, 6-10 HP! Makes a world of difference. Careful. At the higher pressure, the water will cut concrete.

Tried the pressure washing and it had no effect. I used a gas powered 6+HP washer with no luck. The stream seemed to take away some of the stain but only with the fine, high psi stream. I guess if I worked it all weekend I mightbe able to get 75% off, but I gotta believe there is a better way through chemicals.

Have you tried bleach? I used to have mildew stains on the front walk when I lived in FL, sprayed the walks down with diluted pool chlorine in a garden sprayer then rinsed really well and it never hurt the grass at all. Pool chlorine as 12.5% where houshold bleach is ~2%, has a high enough PH so it won't etch the concrete and the chlorine burns away as it does it's job and from sunlight (becomes inert?).

not yet - I was askeerd of the run off but maybe it be bad if I keep it under 5% solution. Good call. Thanks.

My brother occasionally does powerwashing. He was able to get rid of pine resin and the stain pine needles will leave on/in concrete with a very mild bleach solution.

I have to try that here. I've used the gunk solution for Oil Stains. Very effective.