Today while driving out of town (Spokane) I spotted something that looked out of place off to the left. It was several clumps of orangish colored vegetation on a basalt rock outcropping. No way! It looked like it could be cactus. But cactus is not supposed to be wild in Spokane… Okay, I parked the car and walked up to the site. This can’t be true! I about fell over, it was indeed cactus! (Click on the thumbnails for larger view. May take a few moments to load.)
At first I thought it was Opuntia fragilis (Brittle Prickly Pear) because the pads easily detached when I handled the plants. However, things did not look quite right. The pads were flatter than I remembered. Additionally the spines were a little longer and were brownish-orange especially near the end. So I just chocked it up to a different form or variety of Opuntia fragilis.
Another possibility was Opuntia polyacantha (Plains Prickly Pear), but this plant did not look quite like the ones of this species I had seen before. The pads were smaller on the average and the spines were different from what I remembered. I wanted to be sure, but unfortunately I was on vacation and I did not have my plant references and keys with me.
Another thing that bothered me was that as far as I knew there were no reports of wild cactus growing in Spokane County. So, this was something else I had to check out.
Well, I collected a few pads for specimens and headed off to Seattle.
After arriving in Seattle and getting settled in, I connected to the Internet and sent off emails to people in Washington State that I thought may be able to answer my questions. Sure enough, Dick Olmstead and David Giblin of the University of Washington Herbarium quickly replied. Between them I learned that sure enough, the Pacific Northwest Herbaria Database did not list a record of cactus for Spokane County. However, Dick informed me that he had seen some cactus growing on a basalt outcropping behind a motel on the west side of Spokane. I also looked at the National Herbarium’s online database, and learned that they have a specimen for Opuntia fragilis that was collected by V.O. Bailey in Spokane in 1907. It was listed as cultivated and did not state the exact location. David and Dick informed me that my find could be Opuntia Xcolumbiana (Grizzly Bear Prickly Pear).
According to Benny Møller Jensen, this hybrid between Opuntia fragilis and Opuntia polyacantha produces seeds but they are difficult to germinate.
This particular cactus, although limited in distribution, is well known in the Columbia River and Snake River Valleys in Southeastern Western and adjacent Idaho and Oregon. There are a few outlying populations in Northern Washington and adjacent British Columbia. Its morphology is said to be fairly variable. This population in Spokane County falls within a reasonable range although it is some distance from the Snake and Columbia Rivers. I recall seeing a population of Opuntia near the confluence of the Spokane River and the Columbia River many years ago, but don’t know that this is the same cactus.
So, I have some things to check out.
With my specimens in hand, I will press them and send them off to Washington State herbaria to document my sighting. If I have some pads left over I will try to see if I can get it to grow.
Since this is a singular sighting of cactus in Spokane, I will keep this location a secret for now.