When my middle son, who is now 36, was in first grade (1986), he brought home a small sapling pine tree from school for Arbor Day. I planted it in the back corner of the lot and, honestly, totally forgot about it. My back corner is very wet. I never have watered it in the 43 years I have lived here. It was also at the time I was going back to grad school and had little time to worry about the garden.
About 15 years later, I decided that I needed to clean out all the 'crap' that had taken over the back corner. I hired someone to cut down a mulberry and the larger buckthorn, but decided I would take out everything else myself. What a chore. ( I really only got the area completely cleared this year with the removal of the rest of the honeysuckle.)
While cleaning it out back then I found the little pine sapling. It was no more than about a foot tall. I figured that the animals had probably chewed the top off every year. I dug it out and moved it to the middle of the back lawn.
The first thing that happened was that the rabbits, or some other critter, chewed up all the bark on the trunk, what little there was of a trunk. So, I got some flexible tubing and covered the trunk.
The next thing that happened was that the deer ate the top off of it and tore off one of the branches. So, I wrapped the entire tree in that deer netting material. The poor tree was no more than about three feet tall and I had it for about 20 years.
Finally, a couple of years ago, I moved it out of the lawn and set it next to a peony bush on the side of the deck. It is finally growing, nearly six feet tall after almost 30 years. There is hope for it. I took the brave step of removing the cover on the trunk this spring, but with all the rabbits I may just have to wrap it again for winter. It's a real trooper.