Wednesday, June 20, 2012

Lost Landscapes: Coastal prairies before beach grass 

Written May 31, 2012, published June 2012

One of these days I’m going to write a book about all the lost views and vanished landscapes in this area. Until that day comes, here’s a start on the changes:  Simply put, the plants that live on the dunes today are different from those of the past. This change in species also changed the appearance of the dunes.

Barbara Minard, Columbia-Pacific Heritage Museum, proffered this image of the Breakers Hotel in north Long Beach; the date is between December 1900 and 1904. This is a winter or early spring photograph, showing abundant driftwood on the beach, and on the dune, very low vegetation. There’s bare sand in the foreground, and some of it may be black sand. 

Image loaned from Columbia-Pacific Heritage Museum, of the Breakers Hotel, looking north. Note the extensive driftwood on the west (left side of the image), the fence near the middle left, and the treeline, well to the east of the beach and fore dune. 

The Breakers Hotel stood on the dune that formed after the last subduction zone earthquake, which was in 1700. When this photo was taken the dune was 200 years old.  Today, a row of houses stands in this spot, more than one thousand feet east of the present beach. Note that the vegetation is very low and like a patchy turf. American dunegrass is native here, and was growing in the dunes in 1900. It goes dormant in fall and dies back to the ground. Many other dune plants are also perennial and also die back to the ground in winter, so the ground would look partially bare in winter. 

In spring, an image taken at this same location would show wildflowers, including beach lupine, footsteps-of-spring, sea thrift, early blue violet, harsh paintbrush, western buttercup, checkered lily and gray beachpea. By midsummer, dune goldenrod and white brodiaea would be flowering. There may have been patches of tough-leaf iris and nodding onion. Two orchids, hooded maiden’s-tresses and coast piperia, flower in mid to late summer. Beach morning glory, yellow and pink sandverbena and beach carrot thrive in open sandy dunes.  Several other native grasses grew in small tufts and clumps. 

Today, many of these species have all but vanished from the dunes due to the arrival of introduced beachgrasses.  Pink sandverbena is so rare today that when it appeared at Leadbetter Point a few years ago, it had not been seen in Washington for more than 60 years.  Snowy Plovers, Streaked Horned Larks and Oregon Silverspot butterflies were among the animal species that thrived in these open sandy, wildflower-rich coastal prairies. 

Not all dune species have suffered. Still flowering on today’s dunes are beach strawberry, purple beachpea, and patches of yarrow, pearly everlasting and silver bursage.  Sandbur is doing very well, having made a transition from dunes to lawns, to the dismay of bare feet.  Kinnikinnick grows among shore pines, and is a good groundcover for home gardens, in both full sun and partial shade.  As for animals, native voles, shrews, and thatch ants thrive in the beachgrass dominated dunes. 

There are small fragments of coastal prairie scattered along the peninsula; they are no longer on the outer dune line, but well inland, usually more than one thousand feet from the present beach. The diversity of wildflowers in these small remnant patches is amazing.

The vanished landscape that this image hints at is a diverse coastal prairie, rich in colorful flowers, which thrived on summer drought, fire, salt, winter rain and strong winds. In comparison, today’s dunes are very nearly monocultures, dominated by two species of beachgrass.  Someone probably has summer pictures of the dunes from a century or more ago, showing those now-vanished wildflowers. I’d love to see the images of the wildflower prairie that used to flower along the ocean beach.  As for the introduced beachgrasses, these species make gorgeous green grasslands in the dunes, but these grasslands are completely different from the colorful dunes of past millennia. 

Photo courtesy Columbia-Pacific Heritage Museum

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