I have a Etrex ledgend with bursh piles on it. I bought a Mapsource program for it that shows all US lakes. some lakes show more detail than others Oologah depth start at 18 ft. and doesnot show small creek channels. Also you have to down load from your computer if change from Oologah to Eufaula. The chip card Navionics uses would be better but do not know of a hand held unit that offers the card. I do not see why you could not use it to find the brush piles without the Mapsource (lake info).