Sprinklers... Yes... Sprinklers

Why am I posting about sprinklers? I took my morning walk this brisk, clear AM and noticed the amount of sprinklers that are placed at the bottom of sloped lawns. The bottom. Meaning the down part of the slope. California is facing a drought and people have installed idiotic sprinklers that will waste water. It's gravity folks. Install them at the top of the lawn, and the water will move downward, watering all of your grass. Why make the sprinklers work twice as hard, have them on twice as high, when you could be lazy, cheap and environmentally friendly?