I've never posted in this forum but have been reading it for the last couple of years. 3 years ago my neighbors got a trailer load of sod for free and without any soil prep whatsoever installed it under a huge elm tree in my yard as a surprise for me. I am in the Albuquerque NM area and the grass made a small area about 20 feet long and varying from 6 feet to about 12 feet in width. It did okay that first summer because I watered it ALOT but the next spring it was pretty pitiful - did not do well over the winter and only one corner of it still looked pretty good. The rest was pretty patchy. The elm is huge - probably 3 people could not gettheir arms around it so competition for water is fierce. I started reading this forum and applied what I learned and now the grass is lush and green. I have to mow it every 3 or 4 days - I use the highest mow height on my manual reel mower. There's still a few weeds but the grass is gradually choking them out and I pull what I can - not much hand strength due to an arthritis condition. I use whatever I can find in small sizes like cornmeal or alfalfa - can't manage the 50 pound bags from the feed store. I used the baby shampoo treatment to help water penetration as the soil was brick-like. So thanks to all the knowledgeable folks for helping this long-term lurker rehab my little patch of lawn.