Hi. I need to be sure about the species and the problem before I can make any specific recommendations. First, are you sure they are fir trees? Could they be pines or spruce? Those tend to be more common in northeast Ohio landscapes, and both have issues that could be described as a tip blight. Here is a good fact sheet from Ohio State University on how to tell the difference among them. If you aren’t sure, I can help with the ID if you send some good quality images of the tree, including ones taken both close-up (of the needles) and far away (of the entire tree). “Tip blight” in conifers generally refers to Diplodia tip blight, which is a fungal disease. However, it typically affects two-needle pines. This fact sheet from Purdue University provides a good overview of the disease and possible management strategies. In short, it is difficult to manage, and for that reason, many people have avoided growing two-needle pines. On the other hand, it may be that you are referring to damage from the white pine weevil, which is a common pest of white pines as well as spruces. It tends to attack the top of the tree (the leader), which could be considered the “tip.” Ohio State University’s Buckeye Yard and Garden Online newsletter had a good article about them just last week that you can read here. Pruning out the affected terminals can be a good strategy if it is done before adult weevils emerge. They have already done that in southwest Ohio (as noted in that article), but that may not be the case yet here. With a positive ID of the tree and some photos of the affected areas, I can provide more specifics if that would be helpful.