According to the World English Dictionary, a muck rake is an agricultural rake used for spreading manure. A lake rake, on the other hand, is an agricultural rake used for raking weeds out of a lake or pond. The pond here at Breezy Acres not only has weeds, it has muck (also known are mud or mire). So when I rake weeds and muck out of the pond, I think of it as muck raking. It is a very dirty, messy, muddy, mucky business.