Field Journal: 12 September 2018

Note: While I like the page-by-page formatting I used for last week's entry, it is incredibly time-consuming to create. I'm still working out the details of this whole digital-field-journal-thing, so please bear with me!

Mixed Evergreen Forest and Elegant Rein Orchids

Roy's Redwoods

12 September 2018, 09:22 - 11:16

60°F (15.5°C,) partly cloudy

Route: From trailhead at Nicasio Valley Rd., Roy's Redwoods Loop Trail to Hansen Loop. Return via same route. Roughly 2 miles (3.2 km.)

When I first moved to California in the summer of 2016, it was like I’d moved to another planet. Back in Oklahoma, I could name all the trees I passed from a car on the highway, even in winter. Here in California, the forest was just a green blur.

Mixed evergreen forest along Roy's Redwoods Loop Trail

Except for the redwoods. Everybody knows what they look like - or so I thought, until I realized that a lot of those “redwoods” were actually Douglas-fir. Oops.

I needed a crash course in the local vegetation, but where to begin? How do you get to know a place? Plant-by-plant felt overwhelming, so I decided to start by learning about the ecosystems here. In Roy’s Redwoods, there are four ecosystem types:

  • Coast Redwood Forest
  • Mixed Evergreen Forest
  • Grasslands
  • Chapparal

Consider the mixed evergreen forest, which features hardwood & conifers. In Roy’s Redwoods, these forests generally grow on hills with a southerly aspect & include:

  • Douglas-fir - Pseudotsuga menziesii
  • Peppernut - Umbellularia californica
  • Coast Live Oak - Quercus augustifolia
  • Pacific Madrone - Arbutus menziesii
  • California Buckeye - Aesculus californica

Here is an example from the south side of Hansen’s Loop. This site is near a hill summit and receives a good deal of direct sunlight. The dominant tree species here are coast live oak, Pacific madrone, peppernut, and Douglas-fir.

Pacific poison oak is present here, but relatively sparse. Grasses fill much of the space between trees, and toyon, an evergreen shrub, is plentiful. Pink honeysuckle climbs trees, and branches of orange bush monkeyflower reach above the poison oak.

Over on the north end of the Redwoods Loop, the mixed evergreen forest looks a little different. Fir, oak, peppernut, and madrone are here too, but madrone and oak are scarce. This site is in a forested canyon, and it’s the second-shadiest place in the preserve, after the redwood forest. Buckeye trees grow leggy here, easily identified now by their yellowing leaves.

Mixed evergreen forest on north side of Roy's Redwoods Loop Trail

The understory here shares some staple species in common with the Hansen Loop site - poison oak, pink honeysuckle, monkeyflower - but it’s much cooler, damper, and shadier here, so there are ferns: Western sword, California maidenhair, and common bracken. Creeping snowberry and yerba buena wind through the understory and poke out onto the trail.

And then there are the orchids.

Elegant Rein Orchid (Piperia elegans) in Roy's Redwoods

I first spotted the elegant rein orchid on 23 August of this year. Since then, I’ve located 14 plants in the preserve, all of them along the northern side of Redwoods Loop. They grow on steep slopes, sometimes right out of the vertical face where the trail was cut out of the hill. The tallest here is 28 in (71 cm,) and the shortest is 12 in (30 cm.)

Elegant rein orchid and surrounding vegetation

Most flowers in the preserve sport flashy colors - golden, purple, magenta, orange - to attract pollinators like bees and butterflies, but the elegant rein orchid is…well, it’s a wallflower. The greenish-white blooms fade into the surrounding vegetation. So how do they attract pollinators?

By scent. The fragrance is faint during the day, but sweetly pleasant. In the twilight hours, the scent becomes stronger. Lofted above the groundcover on a sturdy stem, dozens of flowers entice passing moths, who find a convenient perch on the flower’s lance-shaped lip. A reservoir of sweet nectar at the tip of the lip is the moth's reward for picking up a bit of pollen on their antennae.

Elegant rein orchid flowers wrapped in spiderweb

Or it could get snared in the loose shroud of spider silk that winds around the orchid. I haven’t found a spider-less elegant rein orchid yet, and a couple are also being used as scaffolding for dome webs.

Senescent elegant rein orchid

The elegant rein orchids have been blooming for weeks here, and they’re all looking pretty spent at this point. I’m hoping to photograph seed pods in the coming weeks, before the heavy winter rains reduce what’s left of this year’s growth to a stem-snag. By late spring or early summer, I should be able to see new stems sprouting from the same tubers.

I also plan to keep a close eye on this area in the coming months. Something about this place makes it home to an orchid I can’t find anywhere else in the preserve; what other strange and beautiful things might find a haven here?

Species Observed:

  • Douglas-fir - Pseudotsuga menziesii
  • Peppernut - Umbellularia californica
  • Coast Live Oak - Quercus augustifolia
  • Pacific Madrone - Arbutus menziesii
  • California Buckeye - Aesculus californica
  • Elegant Rein Orchid - Piperia elegans
  • Beaked Hazelnut - Corylus cornuta
  • False Solomon's-Seal - Maianthemum racemosum
  • Prickly Lettuce - Lactuca serriola
  • Fairy Bell - Prosartes sp.
  • Western Fence Lizard - Sceloporus occidentalis

Next: 21 September 2018.

Previously: 01 September 2018

See also: