I think first grass is a little like first solo--always memorable. My first grass experience was bringing the 182 into Kamiah, ID, a 3000' strip at 1200' elev. after flying over the mountains at 12,000'.
http://img.airnav.com/ap/00201.jpgAt the time, the airport had been mowed only about 3/4 of the length--the north end was still about 2' long. I was there to pick up my pard after he'd been guiding on the rivers for 3 weeks, and he surprised me by bringing a couple of his customers with him, to fly over to McCall. With the extra weight, I was concerned about getting off the ground, although the density altitude wasn't all that bad, probably less than 3000' or so. So we taxied into the tall grass and began the take-off roll from the end. Later at Idaho Falls, we spent some time clearing the grass out of the belly antennas, and later at home, we cleaned the greenery off the prop!

I flew into Kamiah several times over the next few years, to pick him up each summer, but frankly I don't recall any time other than that first time.
Cary