The Quercus pubescens was just about budding but already hosting a brand new gall.
ex Chrysosplenium alternifolium
@giusy87 - could it be a trace of something like gall of Rondaniola bursaria?
? iNat suggestion seems god fit
tree https://www.inaturalist.org/observations/204190775, gall https://www.inaturalist.org/observations/204190776
On Quercus pubescens