One of the peculiarities of living in our part of the Rockies is "White Day." Not to be confused with the Japanese holiday of the same name, it is the day here when virtually every shrub or tree that blooms produces white blossoms, and they all do it synchronously, or nearly so.
Yesterday there were hints, today is White Day. Everywhere I look out my office window, or any other for that matter, there are shrubs and near-trees covered with small, quarter-sized white blooms. In a day or so they'll all be gone, to reappear next year at roughly this time.
Our forest is mainly aspen trees and they produce things humans don't recognize as blooms or flowers. What blooms on White Day is the intermediate understory - various bushes, shrubs, and berry plants. The wild flowers are not included, they'll bloom off and on all summer and be multicolored. The grasses do their own thing but that "thing," similar to the aspens, isn't recognizable as flowers, even if it serves the same reproductive purpose.
Afterthought: I just made the connection to a sale day once celebrated by Macy's Department Stores - White Flower Day. I worked for the organization briefly in the early '60s and remember every Macy's floor walker wore a plastic white carnation in his buttonhole and many did a credible imitation of Capt. Peacock from Are You Being Served.
Second Afterthought: The name White Day has absolutely nothing whatsoever to do with identity grouping and race. It happens all these plants simultaneously produce snow white flowers, most of which are from the serviceberry plant, according to the other DrC.