i need information on how to remove lichen or moss from a granite headstone without harming the stone. this is my mother-in-laws so i better not mess this up!

I've never done this, but I'd try an orange oil or 10% vinegar mixture. The vinegar will kill the lichen, but may not clean it off the stone. Maybe do both treatments? Hopefully someone else can reply. Keep in mind that the vinegar will kill/burn plants if it gets on them.
Ck the site below, you may not want to use either cleaner I suggested esp. the vinegar (acidic).

http://www.rootsweb.com/~kyhende2/CleaningTips.htm

I like the look of lichen on a headstone.

Hydrogen peroxide will work just fine. You could even use a baking soda paste, but rinse well. No need to build up a lot of sodium in the ground.

Speaking of cemeteries, would you be interested in going on a field trip to help with phaze two of a "save this cemetery from arsenic" crusade? Check this out: http://www.dirtdoctor.com/forum/viewtopic.php?t=2203

http://www.dirtdoctor.com/forum/viewtopic.php?p=10152#10152

Since this is your mother-in-law's headstone I thought I'd put in a small word of caution. The vinegar can (but not always) leave marks and discolor, so I wouldn't do that. Orange oil should be okay too, but hydrogen peroxide is the lease damaging and will kill the lichen and it will wear away after a while on its own. The baking soda paste is a good idea to gently wipe away what's left after it's dead.

Good luck and know that you are a sweet daughter-in-law.
Kathe

Hi Nadine, Kathe and Greg. Sorry I've been a little scarce. How are you all doing?

Our church had a voters meeting recently. At the meeting I recommended planting buffalo grass around the headstones. Roundup is used to reduce weedeating time but it causes very ugly weeds to grow. I received positive comments about this idea. I need to double check planting time but I think March is best.

The only weekend not available is March 20. Any other blackout dates for you guys?

BTW, my husband, Cliff, has been taking the dirt/mulch away from tree flares like crazy. Your visit has helped many trees feel much better I'm sure.

We are planning to attend the show in Arlington this weekend. I hope to bump into some of you guys.

Pam

Hello! Great to hear from you! I will be there almost all weekend. I will be at either the Ground Crew booth, the "Crew Members Only" hospitality room, or the Denton Organic Society booth. I screen calls for the radio show on Saturday, but will be at the Home and Garden show after that! I look forward to seeing you there! Bring pictures if you can, we'd love to see them!

Hi Pam, great to hear from you. Good to hear the cemetery is doing so good. Sorry about making Cliff work so hard. Tell him I look forward to seeing what all his hard work has done. The weekend of March 20th is good for me. Plus it would make a great birthday present for me, since my birthday is the 19th. It will make me feel good to know I am helping out to make a part of the world better. Maybe we can hear the occupants thank us for all the hard work Lets plan on that day if Nadine and Kathe are free. Maybe some more organic people will volunteer and we can have a great time again. I will be at the show on Saturday. Maybe we can see each other and promote the trip.

Greg hun March 20 is not good. Our anniversary. We had a blast with you guys but I think we'd like to do something alone.

I was asking for dates that were not good. Maybe March 13 will be good for everyone so we can have an excuse to eat cake and sing Happy Birthday to you.

Hope to run into everyone!

Pam

Pam, sorry I fell asleep, crashed and burned. I re-read your post. We'll have to see when Kathe and Nadine are available. Almost any weekend is fine with me. Maybe we can discuss it this weekend at the show.

The 20th of March is good for me! *************************************************************************oops!!! That is not good for you. The 6th, 13th (our 1st anniversary)! and the 27th are the dates I can not make. First Saturday in April? ************************************************************