Twenty Years Ago

Doctor Odd remembered his grandfather saying “The best time to plant a tree is twenty years ago.”
So, he built a time machine and seed-spreading hoverdrones.
“If twenty years ago is the best time, then forty years ago is better!” Doctor Odd muttered to himself.
He pressed the ENGAGE button…
And he blacked out.
Coming to, he rubbed his head and his hands came back bloody.
“Damn it,” he grumped, and tried to stand up.
His head hit a tree branch.
His workshop was now a thick forest.
Looking around, he saw trees everywhere.
And heard the howls of wolves.