They are almond trees, and I live in northern California (about 3 1/2 to 4 hours north of San Francisco, in a city called Chico.
Chico, California - Wikipedia, the free encyclopedia )
The whole area is full of almond and walnut orchards, as well as some other crops. Did you know that California grows 80% of the entire world's almonds, and they are California's #1 agricultural export? 70% of the annual crop each year is exported to other countries.
These trees are about 4 miles south of Chico. I figured taking the pictures from an overpass across the train tracks would give me a nice view to see a sea of white flowers. Like cherry blossoms, they don't last long.
This is a farming area, countryside where the Sierra Nevada mountains roll down into the Sacramento valley. Every other car is a pick-up truck, and you almost never see BMWs or Mercedes. Growing up here, surrounded by nature, is one reason why I don't really care for big cities, and why I spent so much time in the Japanese countryside (inaka) rather than big cities like Tokyo.