Question
Dear Sean,
    I live on a farm/ranch and would like to install some pathways and driveways that are Eco-friendly. The Decomposed Granite that you talk about sounds great, but do I need to be careful that it is not too dusty or finely ground due to the inhalation dangers of many types of stone dust? Also can you help me with an affordable source between Tallahassee, Florida and Dothan, Alabama or Bainbridge,Georgia area?  Thank you,
                                 terry Jean

Answer
Terry:
I have never heard of any significant inhalation dangers associated with inert materials such as gravel dust. However, repeatedly breathing in any kind of dust can't be good and any gravel when dry will certainly create dust if there is wind and someone drives over it. The solution is to keep it reasonably moist. An irrigation system that hits the driveway every few days should do the trick.As for the size of the gravel, it will have some affect. So selecting a gravel with larger pieces will have less dust and allow for more water infiltration. #57 stone is typically the size most people use and is most composed of 2-3" pieces of stone. You can go up in size but the larger the stone the rougher the ride will be.
In south Georgia, north Florida, etc "Florida Lime rock" is quite commonly used. I don't do much work in these areas where I am responsible for locating a source for stone so I really can not help you there. Try searching the net for "Flordia lime rock" or "M-10" or "crushed granite" or "crush and run" or "crusher run" and add in the local area or city name as part of the search query. If the places you call don't have it, ask them for advice. You can also ask them to ship you a sample. Some might do this for you if you are ordering a bunch.

Best of luck, sorry I was not more helpful.

Sean J Murphy, LA, ISA, LEED AP
Please take a look at these landscape sites:
http://www.seanjmurphy.com
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