I birded Chelsea Road in Perryman (Harford Co) looking for tree sparrows 
today without any luck.  I did find a single Chipping Sparrow which 
seemed rather late to me.  Also:

White-crowned Sparrow - 30+
White-throated Sparrow - 10
Song Sparrow - 25
Savannah Sparrow - 2

Cheers,
Steve Collins
Towson, MD