May 2014

Yesterday I was down at the Glacial Heritage Preserve in Thurston County. I was leading a group of wildflower enthusiasts with Randal Hitchin from the Washington Park Arboretum. Many of you might think of the Pacific Northwest as a place fro prairies, the giant tall grass and short grass prairies of the Midwest get much more attention.

But recently our Northwest prairies are getting there due. Mostly because they are quickly vanishing, only 3% of the original 160,000 acres of prairie are left. And many of those are in a very degraded condition. The Glacial Heritage Preserve is a rather well managed and lovely site. And fortunately during our visit in full glorious bloom.

Dominated by the blue of camas (Camassia quamash) at this time of year, it is hard to ignore the influence of man of these ecosystems. Native American “gardened” these grasslands, removing woody species and burning to encourage lush grow to attract deer fro m nearly 6000 years. The quamash, as they called it was both harvested and replanted as a farmer might tend a field.

The German botanist Hans Roemer, who studied the gravelly prairies of the Northwest, coined a name for these ecosystems. He called them Anthropotic Climax Communities, meaning these plant communities only survived with man’s help.

Once again it is man who is keeping these very rare (the rarest in the United States) ecosystems going. Last year I met one of these prairie-men at Mima Mounds State Park. He called himself a gardener. Certainly many of his activities on the prairies can be likened to gardening. He monitors sensitive plants to ensure their survival, introduces new plants to the mix and most importantly weeds: by hand, with chemicals and with fire.

Prairies are one of the high-maintenance ecosystems., and as we wildflower enthusiasts wandered the 230 acres of GHP yesterday we wonder what would happen if we people didn’t intervene. The group pulled over 100 Scot’s broom plants—one of the strongest and most destructive invaders of the prairies— as we wandered.

Below the rolling gravelly terrain are the small test plots of prairie-restorationists for the University of Washington. Led by botanist Jon Bakker the group has sterilized the soil and sowed seed mixes they created to mimic the prairies of yore. Most of the modern prairies ( pictures above) are a mix of native and European plants at this point. These test plots were some of the most beautiful gardens I have ever seen.

Harsh Paintbrush (Castilleja hispida), western buttercup ( Ranunculus occidentalis) and Sea Blush (Plectritis congesta) in the test plots.

Sickle-keeled lupin ( Lupinus albicaulis) and Field chickweed (Ceratium arvensis) in the test plots.

Golden paintbrush ( Castilleja levisecta) the rarest plant in Washington is making a great comeback in these moist test plots.

Douglas firs encroach on the prairies too. The suppression of fires and a cooler wetter climate in recent history gives then an advantage in these dry soils. Notice the clots of Scot’s broom on the periphery of the maintained prairie. A constant battle that GHP resident custodian Dan Grisboll sees as manageable but not winnable. Again these beautiful prairies need to engage human involvement for centuries to come. They certainly have lured many a gardener in with their beauty; me included.