We have a Memorial Tree Program at our course as well. I started the program, however I did so with twist. Our club suffered from Members donating their own trees, then selecting the location for planting (Next to their favorite green) and to worsen matters, placing plaques on the tree itself.
My solution:
We created a Memorial Tree Fund and placed ONE Memorial Plaque in the clubhouse. This plaque is where we put the names instead of the tree itself. The proceeds from donations for the tree fund ($100 minimum) are given to the superintendent to use as part of his budget. Our superintendent plants several trees each year in locations designated by our Master Plan. We have the best of both worlds. Funding for our planting budget and as well as a nice tribute to our past members in our clubhouse...and not on the golf course.