Split Maple tree
We have a 30 yr old Maple tree that split about 5-6 feet above the ground during a recent storm. We really want to preserve the tree as long as possible. The split is 4-5 inches deep, at least 12 inches long. We had our tree trimmer cut out dead limbs and tied the upper sections together with bolts, cable with a come-along. It reduced the gap. I've not been able to get a response from our local County Extension. Is there anything I should pour in the crack to prevent bugs and/or diseases? Any advice is appreciated.
It sounds like you have done all that you can, you should not pour anything into the wound that will only inhibit any healing that may occur. I would assess the risk of it falling, is it near/leaning over your house or building, would anyone be injured if it fell, etc.