Lumber Gathering

Last question I'll post on this site, probably. My map consists of peasants and I need help on how to decrease their lumber gathering speed. On my map they gather wood way too fast, and it makes it a little unbalanced. Is there any way to change this? Help would be appreciated.

Ability Editor -> Neutral Passive -> Special -> Harvest (Gold and Lumber)

Play around with "Damage done to Trees" and "Lumber Capacity"

If you mean that you have too much Lumber, then just change the costs?

Damage Done To Trees = Number of wood gathered per swing.
Duration (Hero/Unit) = The amount of time in between each swing.

If you need another field explained, just ask.

Thanks for the help guys, and sorry about not changing the costs. I balanced all the costs of all the towers and such before I changed the faster Lumber Gathering.

Thanks for the help.