WW I Army Officer uniform.. what is the patch

[colt45]

[colt45]

front photo

[dustyr55]

The patch belongs to a separate artillery brigade.I couldn't find anything more than that.

Dusty

[colt45]

could it be a National Guard unit ?

[dustyr55]

Not sure about that. I couldn't find too much info. BTW, I was in the 851st ASA Co, Larson Bks in 75-76. We were across the street from the chow hall. Merry Christmas!
Dusty