MinxterBLOOM

In the course of conversation, a friend mentioned that his Siberian irises are about to bloom. This being last week, I expect that the bloom is underway. I remarked that these irises might be the duotone of "Butter and Sugar," a significant breakthrough for Siberian iris. The default color for this iris is blue, lavender, purple, and blue-cast mauve.
Prof. Dr. Otto Wilhelm Thomé Flora von Deutschland, Österreich und der Schweiz 1885, Gera, Germany
"No. They are plain yellow, just like the wild iris that have invaded the Pacific Northwest. My father called the USDA years ago, and was told 'Siberian Iris coming down from Canada.'" I thought on this, thinking he knows rather what he talks about, having grown up near Seattle in a dairy farming family. But, the idea of yellow and species-form Siberian iris continued to nag. What to do? Wiki and google, of course. Wiki says and displays the blue-tones I expected. More wiki work and more google work makes me think that this iris might be Iris pseudacorus, or yellow flag or sweet flag. Pages from the Pacific Northwest suggest that yellow flag marched through this area, beginning at the turn of the century. Let's start with the Wiki-entry on yellow flag here. Nice pictures on the Wiki-page. Here are some pictures courtesy of JC's garden, conveniently located next door. Well, is this the mystery iris? Eventually, I'll report if my sleuthing and instincts are born out. As the final evidence here is commentary about yellow flag's march in the Pacific Northwest.

" . . .the earliest New World record of this plant was made by Fernald who collected it in the wild in Newfoundland in 1911; it was established in British Columbia by 1931; by 1950, Gray's Manual reported its distribution as "Newfoundland to Minnesota"; by 1961 yellow flag was reported to be so plentiful in Canadian swamps as to "have the appearance of a native plant" (Cody 1961)"
"An agressive shoreline weed."
Finally, a tiny thumbnail of "Butter and Sugar" available from White Flower Farm.
Currier McEwen cross ("Butter and Sugar") I like this flower, however, I aspire to adopt the lushious and royal "Caesar's Brother."
"Caesar's Brother," regal Roman

Sources:Permission granted to use under GFDL by Kurt Stueber, www.biolib.de, see Wiki-Commons entry; and White Flower Farm.