This is a really good idea.

We don't mean to be taking away from the spirit of Christmas already, but anyone out there who happens to have a real tree in their home is probably already noticing the number of pine needles that they're cleaning up on a daily hourly rate. You're probably already considering which dump to take it to, or if you can shove it into some local skip without anyone notice, but there is a much better use for your old Christmas tree, one that helps give back to the environment. Throw it into a lake. No, seriously. Joseph Sullivan, the fisheries program manager at East Bay Regional Park District in Oakland, California, told The Verge the following:

"If you imagine a lake bottom that has no vegetation, is really bare, it’s kind of two dimensional. "And by putting these reefs in, you create a kind of three dimensional habitat for fish. "You’re essentially creating a whole ecosystem there."

The introduction of the real Christmas tree (no fakes, please, they don't help anyone) into the lake, once they have been fully un-decorated, allows hiding spots for smaller fish, and more places for them to lay their eggs. It also promotes the growth of algae, which the smaller fish feed on, which the bigger fish feed on, and so on and so on. However, we aren't saying you should dump your tree in the first body of water you come across. If you would like to take the more environmental route with your trees, contact the National Parks & Wildlife Services here, and ask for advice on where to take your fish-friendly tree.