Talk to the workers, not the boss. Tell them you'll give them 10.00, or buy them lunch if they call and you can find a stave. Be prepared to cut and split anything yourself, and away from where they are working.l, for insurance and safety reasons. They will get in trouble if they let you get in and work in their work area/drop zone, etc.. Then leave your card, and a list of suitable wood species for them to pin to the dash of the truck. Be prepared to drop everything and go, because they have schedules and tree jobs have to be done in a certain order. It's hard work, and they fan's be waiting around for you. Expect to show up a couple times and not find anything. If you can find a local, small operator, that's probably better.