I started my day learning of the existence of Moon Trees:
The craters, mountains, and plains of the Moon stretched beneath the Apollo 14 Command and Service Module Kitty Hawk in February 1971. While Commander Alan Shepard and Lunar Module Pilot Edgar Mitchell explored the Fra Mauro region of Earth’s celestial neighbor, Command Module Pilot Stuart Roosa conducted observations, experiments, and scientific investigations in lunar orbit.
Flying passively in Roosa’s personal travel kit on Kitty Hawk 50 years ago was a canister of approximately 400-500 loblolly pine, sweet gum, redwood, Douglas fir, and sycamore tree seeds. Upon return, the seeds were germinated and grew into “Moon Trees” found around the U.S. and world.
“The historic voyages of the Apollo program were about bold exploration and incredible scientific discovery,” says acting NASA Chief Historian Brian Odom. “Apollo 14 included the widest range of scientific experiments to that point in the program, but in the case of Roosa’s ‘Moon Trees’, it was what the astronauts took with them on their lunar journey that has left such an indelible mark on the landscape back on Earth.”
Well worth reading in full, to find out about the connection between Stuart Roosa and the U.S. Forest Service, and the fate of the seeds that returned to Earth with the Apollo 14 crew.
Bonus: I found this link via today's Astronomy Picture of the Day (APOD) which features an 'Earthrise' photo taken from the Apollo 14 command module.