I've noticed some of the post are talking about placing brush. I found a very simple way to keep adding to the pile all year long. Plus it doesn't take any time to build a sizable house for crappies.

In my town the trash collector will take just about anything. They will take tree limbs, brush, hedges, shrubs etc. if the they are tied up and smaller than 3 feet long. The night before the trash pick up I do a little drive through and usually find close to a half a boat of brush already tied and ready to be planted. Just add a cinder block and your ready to go. I usually add these little brunches to existing piles or drop them off in the shallows in less than 6 feet of water.

I place the bunches ( 2 or 3 tied together) in a line along a shoreline so that when the wind is blowing I can let the wind move my float down the length of the brush pile while I stay anchored in one spot..