Theres alot of things you can do, you can go for a one off thing or start a program of ongoing rewards as time goes. Cash is great but it can be forgotten as quickly as its spent. A good set of ratchet wrenches or a decent pocket knife is something they will have for longer.
I learned a while back from my dad that it doesnt matter how well you look after your guys that there is something that can make or destroy a guy-how happy his partner/wife/GF is.
Okay it sounds nuts but if you do something like buy flowers at the end of the day to give to they guys to take home to there wives, or a voucher for some woman stuff, or even organise a pre paid meal out for them, or books for there kids etc, it can go a long way. Wife happy, guy happy.
Another thing is to volenteer them some time on a weekend. Half a day maybe. They choose there own property or that of friends or family and you turn up with the gear and do the trees/garden whatever. Make it so the worker acts as boss to some extent. His family/friends will have a higher respect and appreciation for what he does which will make him happier about what he does. Costs little but means alot.
