regrow trees

[wthef_wc3]

The answer is probably right in front of me but i cant see it, heres the question, how can i make trees regrow. i want to make a boss level for my map and have only a small cluster af trees that regrow so that my hero can cast spells (like that night elf spell that makes little trees i forget wat its called)
any idea?

 

[Jelle284]

change the scale and every 20 sec make em larger until its finish