This photo is dated 1900. Tropico was an independant agriculural community established in 1887 and annexed by Glendale in 1918. The photo caption reads;

“The nineteen workers are at center and are arranged in two lines. The men and women in the front line are kneeling near the ground, while the men behind are standing. Everyone is wearing long pants and broad-brimmed hats. There are many rows of strawberry plants growing on the ground. In the distance at right, a line of tall trees can be seen near a small wooden building. “

Publisher: University of Southern California Libraries (digital) 
Public Domain