Actually that thing with the juicy fruit gum is an ol wives tale. I know a lot of people swear by it, but there are generally other reasons why the critters go away after doing that, and it is actually pure coincidence. Moles are true carnivores, and are not attracted to the smell of the gum what so ever, so they will not eat it. This is the same reason why most mole poisons do not work by the way. they are gimmicks.
The best way of controlling moles is by going after their favorite food source, the grub, then the moles will go off in search of grubs, and leave your lawn alone. The only problem with doing this is, that grubs are most active twice a year, late
spring and late summer, and the moles will generally stick around until these times and when the grubs don't show up, they will leave.
Grub Ex is a very good product, and one application works the entire season, but it must be watered in right after the application, and the application must be done at least 3 weeks before the grubs become active in your area.