I planted a 3 year old thundechild apple tree about 4 years ago it was attacked by the apple borer and it broke in half at the base. There are about 5, 2 foot healthy looking sucker branches growing from the base. Should I leave them or should I only keep the healthest one? What are the chances that these suckers have the apple borer in them. Or should I cut my loses and dig up the base and forget about it? thanks