Evening Program
November 8, Wednesday. Restoring our Salt Marshes: Control of Spartina densiflora in Humboldt Bay. Andrea Pickart with Humboldt Bay NWR will describe the effects of invasion by dense-flowered cordgrass, and progress in restoring these salt marshes over the past 15 years. Register on Zoom on the website, or gather at Six Rivers Masonic Lodge (251 Bayside Rd. in Arcata). Refreshments at 7:00 p.m. Program at 7:30 p.m.
Field Trip
November 5, Sunday. Redwood House Road Day Hike. We will walk 2-4 miles on this unpaved, little-traveled road off Highway 36 to get a taste of inland grassland and forest. See hike #98 in Hiking Humboldt volume 2. Meet at 8:30 am at Pacific Union School (3001 Janes Rd., Arcata) to carpool, or 9:00 am at Kohl’s end of Bayshore Mall parking lot. Tell Carol you’re coming: 822-2015 theralphs@humboldt1.com.
Native Plant Nursery
Our nursery will be open for sales on our regular workdays and times, Wednesday, Friday and Sunday 10 am – 1pm. Check our website: northcoastcnps.org for a list of available plants and to see which plants are on sale, and to find any additional hours that the nursery may be open for the month of November.
Rohner Park Restoration Work Party
November 18, Saturday, 9 – 11 am. Help remove invasive plants in Fortuna. Meet at the Fireman’s Pavilion. Contact Steve: 707-601-6753.
Disturbance and Rare Plants: “The Good, Bad, and the Benign”
by Dave Imper, Rare Plant Chair, North Coast Chapter
Disturbance such as fire, grazing, wind, disease, or direct human manipulations is a critical factor in determining the structure and composition of many plant communities. Its effect on individual species can vary dramatically with the character of the disturbance, from highly beneficial to just the opposite. More often than not though, disturbance is necessary for the occurrence of rare species. In 2016, I estimated that of all of the California Rare Plant Rank 1 and 2 flowering plant species in Del Norte and Humboldt counties, roughly 80 percent were associated with disturbance of some kind. Characterizing disturbance as “good” or “bad” requires intimate knowledge of the species’ biology, and monitoring of the disturbance, as illustrated by the following case.
In the mid-90s I was hired by Humboldt County to conduct rare plant surveys for proposed bridge replacements. I discovered a large population of the rare Wolf’s evening primrose (Oenothera wolfii) growing adjacent to a bridge. This species requires disturbance in the form of windblown sand and occasional roadside mowing. I recommended the County ensure the existing roadside sandy material (which included recent seed produced by the primrose), be carefully salvaged and respread following construction. Unfortunately, compacted road-base material was used instead, causing the population to blink out within a few years.
Many kinds of disturbance, including controlled grazing and fire, are highly beneficial to rare plants, but the devil is in the details. If you see a rare species you think may be threatened, do not hesitate to report it to our CNPS chapter, through our website.