Pseudotrillium rivale in Josephine County, Oregon
When I went down to Josephine County, Oregon, in March 2026, many of the Pseudotrillium rivale were almost done flowering. Poor timing has never stopped me from finding something of interest before - and I didn’t let it stop me this time.
Three out of the four locations were I saw extensive populations of Pseudotrillium rivale were east-facing slopes, typically adjacent to watercourses - some seasonal drainages, others identified as named streams/creeks.
They often occurred with Erythronium citrinum, sometimes within a grass matrix and other times in a more gravelly condition. There was typically some kind of tree and/or shrub canopy.
Leaf patterning varied widely, sometimes even within the same grouping of seedlings. Leaves ranged from almost pure olive-green with poorly visible veins to pewter-toned with highly prominent veins. The majority of plants had some kind of light but not highly distinctive veining.
Flowers offered a variety of aspects (pendant, semipendant, upright), petal shapes (narrow and thin arrowheads to larger heart-shaped petals making up full flowers), and patterning (heavy purple freckling to almost pure white). I did not see any dark-leaf forms, even with purple splotches, or any with pink to solid purple flowers.
I’m especially interested to explore other populations besides these to see the variations in leaf and flower form. Let me know of anywhere you’ve seen particularly interesting variations.
Lightly pink flecked Pseudotrillium rivale growing through a grass matrix with fallen branches under a tree canopy.
Almost white flowered Pseudotrillium rivale growing with Erythronium through a grass matrix under a tree canopy.
Pseudotrillium rivale growing through a grass matrix with scattered mossy boulders on a slope.
Pseudotrillium rivale growing abundantly interspersed with Erythronium citrinum on a slope with many mossy boulders.
Silver veined leaf form of Pseudotrillium rivale growing at the top of an exposed gravel slope with a few boulders.
Pseudotrillium habitat at slope above road cut with Darlingtonia seep.
Solid olive green leaf form of Pseudotrillium rivale with not very prominent veins and pale colored flowers.
Even within adjacent plants, the level of leaf vein prominence varies dramatically in Pseudotrillium rivale.
Light-veined Pseudotrillium rivale with pendant flower.
Prominent silver veins and pale purple spotted flower form of Pseudotrillium rivale.
Pseudotrillium rivale pewter leaf form with prominent light veins.
Flowers of Pseudotrillium rivale differ widely in how upright vs pendant they’re displayed, as well as their petal shape and extent of purple spotting.
This Pseudotrillium rivale seedling has beautifully shaped petals with moderate purple spotting.
Another Pseudotrillium rivale with beautifully shaped petals and light purple spotting.
This Pseudotrillium rivale has narrower, arrowhead-shaped petals with light purple spotting and most are pendant.
Full arrowhead-shaped petals on this seedling Pseudotrillium rivale, but very very light purple freckling.
This Pseudotrillium rivale growing under an Umbellularia californica has beautifully shaped petals that are almost pure white with no purple freckling.
Pseudotrillium rivale with Erythronium citrinum on a hillside in dappled shade.