What was the color of the first Girl Scout uniform?

The first Girl Scout uniform in 1912 was actually blue. The color was changed to khaki in 1914. It wasn't until 1928 that the Girl Scout uniform became green -- the color most people associate with Girl Scouts. Today, there are different uniforms for each of the five age levels, as well as an adult uniform. The colors? Shades of green or blue (or brown and blue for Brownie Girl Scouts), but you should see some of the new styles tapestry vests, patterned tights, shorts and slacks in addition to the always popular sash and vest. http://cheesecakeandfriends.com/troop1440/history.htm

girl scouts/guides was blue and for guides is still blue.(Canadian)

well... if you want to be technical. Back in the day (1908) when the Girls gatecrashed the Boy Scout rally at Crystal Palace and started the Guiding movement, they turned up as 'Girl Scouts' wearing a mixture of Scouting uniform and thieir own clothes (the skirt):

'They wore a long khaki or Lincoln green skirt, a khaki blouse, and a khaki brimmed hat'

It wasn't until 1909 that the colour blue was adopted

referenced from http://www.bbc.co.uk/dna/h2g2/A5103613

The question was about Girl Scouts, not Girl Guides.