Recycling Christmas trees
The trees can be planted in the snow in places where the soil is alkaline. The falling needles will lower the pH, which is helpful on strawberry beds, on bulbs, on perennials, especially on alkaline prairie clay soil. The flowering bulbs get super-vivid colors with that treatment. Where the soil does not have a snow cover, the branches can be cut off and used to cover bulbs and perennials. Hang bird feeders on the branches.
As support for climbing plants
In the spring, plant the trees in large holes into you throw manure or compost and cover with soil. Then I stick in the seeds of cucumbers, pole beans, squash, morning glory, and anything else which can climb up on the tree.
Chop off the branches and form a teepee with the tips of the trunks tied together. These teepees will support climbing plants, including large pumpkins.
Municipalities plant the trees in the snow as decorations and as windbreaks for skating paths or winter festivals. Later they use large chippers to make chips for gardens and parks.
For fish breeding
A water bird refuge throws the trees onto the ice of its large ponds. In the spring, they sink to the bottom and create breeding grounds for the fish population.