I imagine it was a bit of challenge to make a film that has no characters other than trees - and not trees with faces, either. I think the atmosphere of the peaceful forest, and then of something very wrong and malevolent appearing in it, comes through quite well. As for the possible political aspect - yes, it's hard for me not to see this as a veiled critique of the Soviet government and a prediction of its collapse (which was still 3 years away, but by this point things were obviously beginning to unravel). But the message could be a broader one as well - about how seemingly invincible and sturdy things may yet have an unexpected weakness due to their very nature.