The Collaborative International Dictionary of English v.0.48:

Palo \Pa"lo\, n. [Sp. See Pale a stake.]
   A pole or timber of any kind; -- in the names of trees. [Sp.
   Amer.]
   [Webster 1913 Suppl.]

U.S. Gazetteer Places (2000):

Palo, IA -- U.S. city in Iowa
   Population (2000):    614
   Housing Units (2000): 251
   Land area (2000):     1.252031 sq. miles (3.242744 sq. km)
   Water area (2000):    0.002358 sq. miles (0.006108 sq. km)
   Total area (2000):    1.254389 sq. miles (3.248852 sq. km)
   FIPS code:            61230
   Located within:       Iowa (IA), FIPS 19
   Location:             42.062201 N, 91.793126 W
   ZIP Codes (1990):     52324
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Palo, IA
    Palo