The DC Government seems to still be hanging on to 2011 as there's not much information about Christmas tree or hazardous waste disposal for 2012 out there yet. It seems that in DC, free curbside pick-up of Christmas trees will run January 3-14, 2012. After January 14, trees are not recycled but can be picked up with trash on regular delivery days as space in the trucks allows. Find details at http://dpw.dc.gov/dc/dpw. This website has info on Christmas tree recycling in MD and VA.
As for wreathes, why not throw them on your yard and let them decompose over the next month or so? You can also take them off the wire, and throw the branches into the Christmas tree pile...or better yet, into your fireplace.