Question
Two years in a row my crazy boss at a summer camp has insisted that we replant our Christmas In July tree. Two summers ago we basically stuck the pine tree with its crisp, flat, cut stump right in the ground, and laughed as she insisted that it would grow roots. We came back this past summer and it had not, and it was brown and dead. Then, after this past Christmas In July, she told us to plant our Christmas tree in a shallow area near shore in the lake, claiming that the water would help new roots grow. We don't believe this could ever happen, but we cannot wait another whole year to see if she was wrong again. Is it possible to regrow roots of Christmas trees if you plant them in a lake, or is she just crazy?

Answer
I would not say she was "crazy" but badly misinformed.

Cut Christmas trees will NOT form roots and should be discarded as soon as needles start falling.

Occasionally, Christmas trees will develop new shoots and plants appear to be actively growing for several months. However, no records indicate any cut trees ever rooting.

These trees are cut and are dead. The same thing as cut flowers--keep them watered and they will stay green for a while but they will not grow if "stuck" in sand or soil. If you want a living Christmas tree then but one that has a root ball and in a pot. These can be planted out.
Most people who live on a lake "plant" their discarded Christmas tree in the lake as a fish bedding area to attract fish.

Any tree planted in July with a root ball would have a difficult time unless special care is taken--not the correct time to plant trees. Cut trees are just that they are cut and this killed them and sticking them in the ground means that you now have a dead eye sore along the lake. If you are going to continue this Christmas in July celebration I would suggest getting an artificial tree and afterwards plant it in the box for use next year.