Answer: I believe the ants are in your tree because there are aphids feeding on the leaves (the curling is the give-away). The ants 'herd' aphid colonies and milk them of honeydew, a sugary residue that they excrete while feeding on the leaves of your tree. Spray your tree with a strong stream of water to dislodge any aphids you find. If you could somehow spray all the aphids with insecticidal soap, that would take care of them. But it's difficult for a homeowner to do - you may have to hire a professional. Insecticidal soap is lethal to aphids but won't hurt you or your fruit. To keep ants from climbing up your tree, place 'Tanglefoot' at the base of the trunk. Tanglefoot is an extremely sticky substance that traps insects if they fly or walk onto it. To protect the trunk of your tree, first wrap it with paper and apply the Tanglefoot to the paper. You may have to remove the paper coated Tanglefoot trap and replace it as it becomes filled with ants - if there are enough dead ants trapped, live ants will use them as a bridge and cross the Tanglefoot barrier!
Best wishes with your cherry harvest!
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