Most fruit trees are very soft wood including cedar and will only last in the water a season or two. The hardwoods like oak,hickory,osage orange, iron woods, etc. will last a lot longer. But any type tree other than toxic trees(holly, walnut,etc.) are better than nothing and cedar has been used for years mostly because right after Christmas they are so easy to come by as people are throwing them away. Fish habitat "Build it and they will come".