It takes skill to maintain a lawn, and it is surprising how many lawns most of us take for granted: stadiums, schools, office parks, public parks and government facilities, highway median strips, and, of course, home back yards. All of these lawns need the services of lawn maintenance workers. In this profession, it’s important to know how to operate, adjust, and make minor repairs to mowers, gas-powered trimmers, and even chain saws. It is also important to observe the condition of the lawn and make recommendations to groundskeepers and other supervisors, since the timely application of weed killers, pesticides, fertilizer, and even water can stop a problem before it becomes serious. The work is physically demanding, and may have to be done in hot, humid conditions one day and damp, rainy weather the next. But considering how much beauty a thick, green park or other lawn adds to people's lives, it can also be very satisfying.