Just a little article about shifting flowering dates in the Rockies. Thought it might be of some interest. I'm trying to keep track of this kinda thing here in Cascadia as it seems like taking ques from nature is one of the best ways to plan in regards to the plant portion of permaculture. Seasons in my neck of the woods seem to be shifting by several weeks in each direction as well - though I'm no expert who's spent 39 years on the subject like the author of the study this article is about.
I gotta imagine that this kind of change has been happening in all kinds of different places and times.
For example, our apples and pears bloomed simultaneously last year due to an unusual spring weather pattern, but normally they don't.
Which meant the one holdout Asian pear got pollinated this year, which it usually doesn't.
Deserts bloom with rain-triggers; and it seems like in areas where snow-melt is the primary moisture for the spring, or where rain events are less common, there's a lot of concentration of sprouting and blooming at certain times.
I wonder if plants moving uphill (those that can't easily migrate north with climate change) could end up blooming in shorter bursts at their new elevations, even as plants at the same elevation might start enjoying a longer window, or even have to adapt to a heat-dormant summer period that wasn't an issue formerly.
Which ties this in to another question I've been mulling lately, about the distinction between species.
If subspecies move different directions at blooming time (early-bolting and late-bolting varieties, for example), they could become temporally distinct populations. I believe there are a few species that tend to produce male and female flowers in a distinct sequence, to maximize cross-pollination instead of selfing.
But it's even more interesting to speculate whether any separate subspecies might get jammed back together by coming into bloom simultaneously.