We have a tree that does not look well. The leaves are thinning and upon closer examination the leaves are actually rolled up in to cocoons and filled with tiny white bugs. Any ideas?

Welcome to Garden.org, @K8brityahoocom !

Those actually look like little seed pods to me (although I could be wrong...)

It would be helpful if we knew where you are located; and if you know what type of tree that is, it would be very helpful as well! (The leaves remind me of a locust tree?)

Honeylocust pod gall midge:

https://www.google.ca/search?q...