What are the environmental repercussions of that? I don't do any chemicals, weed killer, or chemical fertilizers. All I do, to feed the soil and not the grass, is dolomitic lime and organic fertilizer.

none that i saw. it just suppresses growth hormone of plants for a couple of weeks so they grow at half speed or less. less mowing. less watering. less fertilizers. etc. for plants that are not grass pgrs usually slow down vertical growth and promote later branching/density

PGR is just so expensive to use.

yea. generics cost 1/3.still not cheap. yet, i decided to try one this summer, because mowing grass that grows as crazy on the hill (frontyard) at 90sh weather - it's just not my definition of fun