Three-birds Orchid -- Triphora trianthophora
McCormick's Creek State Park, Owen County, Indiana.
Here's what a small grouping of this orchid looks like when in flower. Individual flowers only stay fully open for one day. On a day when flowering takes place, it is synchronous throughout the entire local population. The following day, there will be none or very few in the entire local population that will be in flower. Then there will be a period of days (sometimes a week or two or perhaps even more) before flowering will occur again.
When flowering occurs seems to be associated with a significant drop in the overnight temperature of 5 degrees or more after which flowering occurs about 48 hours later. My attempts at catching them in flower after such a temperature drop have been largely unsuccessful. I guess my understanding of the whole scenario is not particularly good (I've never been good at math!). In any case, I do manage to catch them in flower from time to time, apparently more out of plain luck than anything else.
Two years ago on Aug. 3, 2021, there was a massive regional flowering event that took place with this species since three different persons (me included, again at McCormick's Creek SP) witnessed flowering on that day in three separate Indiana counties in central Indiana. So, whatever triggers flowering can operate on a very large geographic scale!
As you can see from observing the hanging, spent flowers on three of these plants, there had been at least one blooming previous to this one. Based on the number of remaining buds there will be one or two more rounds of flowering yet this year.
Three-birds Orchid -- Triphora trianthophora
McCormick's Creek State Park, Owen County, Indiana.
Here's what a small grouping of this orchid looks like when in flower. Individual flowers only stay fully open for one day. On a day when flowering takes place, it is synchronous throughout the entire local population. The following day, there will be none or very few in the entire local population that will be in flower. Then there will be a period of days (sometimes a week or two or perhaps even more) before flowering will occur again.
When flowering occurs seems to be associated with a significant drop in the overnight temperature of 5 degrees or more after which flowering occurs about 48 hours later. My attempts at catching them in flower after such a temperature drop have been largely unsuccessful. I guess my understanding of the whole scenario is not particularly good (I've never been good at math!). In any case, I do manage to catch them in flower from time to time, apparently more out of plain luck than anything else.
Two years ago on Aug. 3, 2021, there was a massive regional flowering event that took place with this species since three different persons (me included, again at McCormick's Creek SP) witnessed flowering on that day in three separate Indiana counties in central Indiana. So, whatever triggers flowering can operate on a very large geographic scale!
As you can see from observing the hanging, spent flowers on three of these plants, there had been at least one blooming previous to this one. Based on the number of remaining buds there will be one or two more rounds of flowering yet this year.