Hi.  Last fall I treated my 140 colonies with extender patties for tracheal
mite and AFB control.  I am noticing that many colonies now have about half
the pattie remaining, but I'm not sure if this terramycin is still active.
Should I remove the residue and treat again, or will the residue be
effective thru early spring?
 
Does anyone have knowledge or an opinion regarding terramycin stability to
help with the above question?  Thank you.
 
Jim King, Riegelsville, PA