We have a red oak that stems are falling. There is a clean break and they seem to be 5 to 6 inches inches in length with about 18 leaves on these tips. The leaves are healthy and this isn't a squirrel problem.
Arapahoe County Colorado trees and shrubs
I feel your pain (my red oak is also shedding all the new twig growth this year). If they are the same then you have may kermes scale. You may wish to bring in a twig sample to confirm the diagnosis; 6934 S. Lima St Suite B. Centennial CO
Attached is a website with some information on steps to take to control future kermes scale outbreaks. Your tree will be fine this summer and should be good in future years, but the website is there to take action if you want.