Sci fi movie with aliens that were trees

A young astrophysicist searches for sinister extraterrestrials looking for sanctuary for their comrades by possessing the bodies of humans.

Alien biologists arrive on earth to study humans. They shoot them with tranquilizer darts, weigh them, measure them, and put radio tracking collars on them. Then they shave their heads and paint them green and release them. This is the story of their study. Space aliens, hippies, cavemen, space rodents, and a ninja…. THIS MOVIE GOT EVERYTHANG.

Amidst a huge storm, a couple experience an encounter with an alien species.

An alien race on Earth tries to co-exist with humans, despite the segregationist restrictions that have been placed on them.

Hikers find a secret grove of extra-terrestrial marijuana and must fight for their lives when they anger the other-worldly forces protecting the plants.

Aliens in human disguise commandeer a rural airport during a snowstorm. To survive, the people trapped inside must determine which of their own is not of this Earth.

Nolan Wood is a pilot who uncovers a plot to promote the ecological destruction of Earth in order to pave the way for alien colonization. Now, with the help of a dedicated, open-minded doctor, Wood embarks on a desperate race to convince authorities of this conspiracy - while staying one step ahead of his alien pursuer - in this cautionary tale.