Natural History Wanderings

If you travel from Mariposa along Highway 140 to Yosemite, look for a good number of the late spring flowers. Interestingly, one of the first flowers to bloom at Yosemite’s lowest elevations was the waterfall buttercup (Kumlienia hystricula) during the second week of December, and it remains in bloom in late June!

The El Portal area continues to offers whites, yellows, and pinks—especially the purplish-pink of clarkia, also referred to as farewell-to-spring, growing in masses on the canyon’s grassy slopes. Botanists refer to the common farewell-to-spring more specifically as Dudley’s clarkia (Clarkia dudleyana)—identified by its wedge-shaped petals, often with purplish dots and streaks of white. Multiple species of the four-petaled clarkia are in bloom including bilobed clarkia (Clarkia biloba), elegant clarkia (Clarkia unguiculata), four-spot clarkia (Clarkia purpurea ssp. quadrivulnera), forest clarkia (Clarkia rhomboidea), and Fort Miller clarkia (Clarkia williamsonii). Farther from the park’s entrance on Highway 140 grow Mariposa clarkia (Clarkia biloba ssp. australis), and Merced clarkia (Clarkia lingulata). The rare Merced clarkia is a textbook case studied in universities for its instant speciation from the bilobed clarkia. “

 

“Along the Highway 140 route, notice the large number of flowering shrubs and trees along the hillsides. The yerba santa shrub (Eriodictyon californicum), with its leathery leaves, displays lavender flowers crowded in scorpioid cymes. Culturally, yerba santa has highly aromatic leaves used as a decongestant or dried either to smoke or chew as tobacco. The evergreen shrub chamise (Adenostoma fasciculatum) displays small white flowers, against its resinous foliage, on dry slopes and rocky soils in the oak-woodland zone. Enjoy this short window of chamise’s sea of foamy white before flowers turn a rather drab brown for the rest of the summer season. Also, the California buckeye (Aesculus californica) blooms peak with picturesque inflorescence in an elongated stance. By mid-summer, the buckeye tree will bear smooth leathery capsules as the plant goes dormant to survive the California heat. The large reddish-brown blooms of spicebush (Calycanthus occidentalis) might catch your eye or your nose due to its strongly aromatic flowers and foliage, especially when bruised. And, a late spring bloomer is the California mock orange (Philadelphus lewisii), with showy white flowers that could be mistaken easily for buck brush (Ceonothus cuneatus). Many gardeners might be familiar with mock orange due to its long use as an ornamental. When you reach Yosemite Valley, look for mock orange at the base of Bridalveil Fall.

Still noticeable along Highway 140 roadside is the bright yellow common madia (Madia elegans)—which flowers in the spring and into the summer— jewelflower (Streptanthus tortuosus), and blazing star (Mentzelia crocea). Also, look for small-flowered alumroot (Heuchera micrantha), with stems up to 35 inches long, reaching out from shaded crevices. The white-flowering yawning penstemon (Keckiella breviflora) can have a rather straggly look growing on sunny, south-facing slopes in the lower canyons. Despite the name, yawning penstemon is no longer in the penstemon genus; modern genetics allowed botanists to distinguish unique genera.

In Yosemite Valley, the bouquet of spring wildflowers can amaze wildflower enthusiasts. Find a showy display of Gray’s lupine (Lupinus grayi) throughout the Valley, under ponderosa pines and incense-cedars, particularly along Southside Drive, with one-sided bluegrass (Poa secunda ssp. secunda) mixed in. Spotted along the rocky areas of the Four Mile Trail’s lower portions are Draperia systyla in the waterleaf family, Pacific stonecrop (Sedum spathulifolium), and pride of the mountains (Penstemon newberryi). In El Capitan Meadow, the impressive white blooms of the Western azalea (Rhododendron occidentale) can be found growing under California black oaks. The showy white flower display in Cook’s Meadow is cow-parsnip (Heracleum lanatum). Approximately 80 species of Heracleum exist in the world, named after Hercules presumably for the large stature of some species; however,Heracleum lanatum is the only Heracleum species in North America. Also in Cook’s Meadow is the Jeffrey shooting star (Dodecatheon jeffreyi). Of the 14 shooting star species in western North America, the Jeffrey shooting star is the most common in Yosemite—reaching its peak in wet areas of mid-elevation montane meadows. Known as one of the early spring wildflowers in the lower elevations, shooting stars are pollinated by bees that “grab” the anthers of the plant and vibrate their wing muscles at a frequency that shakes the pollen loose.

In shallow lake margins in western canyons, watch for bladderwort (Utricularia vulgaris), which is an aquatic perennial with free-floating stems. Bladders are numerous and attach to leaf segments with yellow flowers rising up above the water. As the plant grows, the ovary matures into a capsule like a little white lantern.

Beyond the Valley, where else should wildflower viewers go? During early summer, visit the Big Meadow area in Foresta for post-fire blooms where legumes are taking advantage of a nitrogen shortage caused by the 2009 Big Meadow Fire. These legumes thrive in areas low in nitrogen. Instead, they work with a nitrogen-fixing bacteria, Rhizobia, to gather nitrogen from the atmosphere. When the legume dies, plant-friendly nitrogens are released into the soil that other plants may utilize. Expect acres, literally, of Gray’s lupine (Lupinus grayi), with pockets of other legumes throughout, including dwarf lupine (Lupines nanus), harlequin lupine (Lupinus stiversii), bicolor lupine (Lupines bicolor) plus clovers, and lotuses. Access the Big Meadow area from Foresta Road near the El Portal park administrative complex—but plan a LONG walk because this gravel road is not suggested for driving. Or, access the other end of Foresta Road and the Old Coulterville Road from the community of Foresta, which is off the Big Oak Flat Road (Highway 120) inside the park.

If entering Yosemite from the west on Highway 120, plan a sidetrip to Hetch Hetchy to view the striking pink-and-yellow Harlequin lupine (Lupinus stiversii), Sierra stonecrop (Sedum obtusatum), and madia (Madia elegans). It’s a perfect time to take a walk to Wapama Falls, which is running strong like all of Yosemite’s waterfalls.

As you adventure to higher elevations still covered, perhaps, partially by snow, watch for “parasitic” plants—like the snow plant (Sarcodes sanguinea) and spotted coralroot (Corallorhiza maculata)—known to rise up out of the snowmelt. These parasitic plants lack the green pigment chlorophyll required to synthesize sugars in sunlight, therefore, feeding on soil fungi.

Non-Native Species: What else might you see on the Sierra wildflower landscape? It’s possible to find several plants that just don’t belong. Look for the dramatic matilija poppy (Romneya coulteri) off Highway 140 in the El Portal administrative area. The size of the flower wows onlookers as this plant has the largest flower of any species native to California. The matilija poppy, however, is native to Southern California and was introduced in the El Portal area where it has spread quickly due to an extensive root system that easily crowds out Sierra Nevada native flora.