Ants on Cherry Fruit

Last summer my 1 year old sweet cherry trees bore 4 cherries and before they became ripe enough to eat for myself, I found black ants eating them. Is there any way to keep ants off of produce? I thought about applying cooking oil around the trunk of trees to keep them from climbing up. Would that hurt the tree?

Ants are usually a secondary problem. They were probably attracted to the sugar in the ripe fruit. The real problem may have been birds. They may have damaged the fruit leaving openings that attracted the ants and allowed them to feed on your cherries. Avoid putting sticking substances directly on the tree trunk. There is concern about the absorption of light and long term impact on the health of the tree. Once your tree starts producing you may need to use scare tactics or netting to keep out the birds. Also monitor for codling moths that can injure the fruit and create entryways for the ants.