Quick background: I recently renovated my bermuda lawn and I'm trying to learn as much as possible before the end of the growing season and to get ready for the upcoming dormant and spring greenup.

Been reading a lot about fertilizer application and I'm trying to avoid burning my lawn with excessive fertilizer application. Seems that occurs semi-frequently to us newbies. I have a couple of questions. I came across some information regarding grass burn both here and Scotts. From what I can tell, if you overapply fertilizer, then it is a good idea to put down lots of water. Ok. Got it. I'm curious as to the specific reason(s) why. Scotts says this:

"It is a law of nature called reverse osmosis, and that is what causes the burning of the lawn," Boylan said. "The grass doesn't actually burn, it dries-up because it is giving-up moisture." Osmosis is the process by which plant roots take in moisture, and osmotic balance is essential to a healthy lawn.

Sounds reasonable. So, IF I do overapply is it possible both in theory and in practice to stave of burn by watering the day of the next day etc? That is, provide water to the plant as it dumps it out. Or, is the application of water primarily to wash the nitrogen away? Is the time frame for which lawn burn occurs over several days (as long as excessive nitrogen is present)?

Ok. This leads to my next question. In an effort to avoid the burn, I'm in the market for a fertilizer spreader. I want a spreader of reasonable quality that will provide accurate application rates. I use Lesco products but Lesco's spreader is out of my range! I'm looking at Earthway's spreaders as I have heard good things about them.

However, compared to many of the folks here, my front lawn is a mere 1650 sqft and my back is about 3700 sqft. If I understand application rates correctly (and that is an IF) my front lawn needs about 4.5 lbs of product (assuming 39-0-0 slow-release urea). Isn't a rotary spreader that holds 50lbs of product overkill? The Scotts are much less, but they look much less too. Do any of you have experience with Earthway's shoulder spreader that can be had for ~1/3 of their 2100P walk-behind? The issue is primarily with space. I realize the walk-behind is much more convenient. But, I have a lot of room for the larger spreader in my shed.

Shoulder

http://earthway.com/2750Shoulder2006.htm

2100P

http://earthway.com/2100p2006.htm

Thanks.