Evening Program
February 14, Wednesday, 7:30 pm: California Desert Plants: Ecology and Diversity
The desert areas of California include the northwestern portion of the Sonoran Desert, the largest part of the Mojave Desert, and the western margin of the Great Basin. Michael Kauffmann, co-author of California Desert Plants (Backcountry Press 2022) will take us on a journey to explore these vast and intimate desert landscapes through their diverse, colorful, and dynamic flora. Attend in person at the Six Rivers Masonic Lodge (251 Bayside Rd. in Arcata) or watch on Zoom. (Register for Zoom at www.northcoastcnps.org).
Field Trips/Tours/Workshops/Workdays
Native Plant Garden Tour
Saturday February 3, 1:00 pm to 2:00 pm
Join the monthly tour at the Arcata Community Center Native Plant & Wildlife Garden with “bugman” and life-long gardener Pete Haggard. Pete will show that wildlife will come to the city if native plants are provided. The garden is on the hillside to the left of Healthsport, Arcata (300 Community Park Way), opposite the Arcata Community Center. This walk repeats every first Saturday. If it rains, bring an umbrella.
Moss Walk and Microscope Session
Sunday February 4 (rain postpones to February 11)
Double billing: (1) a beginners’ moss walk, then (2) a microscope session. The walk starts at 9:30 am at Headwaters Forest Reserve Elk River Trailhead. The trail is paved and level. A photoguide of the more spectacular bryophytes will be provided. We’ll be done walking around 11:30 am. People are then invited to move to College of the Redwoods to picnic near the CR Cafe. At 1:00 pm we will reconvene in SCI 102 to look through microscopes at organs of note in the lifecycle of the plants we saw on the walk. People can attend the morning and/or the afternoon session. To carpool from Arcata, meet at Pacific Union School at 8:45 am. Leaders are Paul Wilson (paulsiriwilson@gmail.com) and Karen Reiss. Register via northcoastcnps.org.
Rohner Park Restoration Work Party
Saturday February 17, 9:00 am to 11:00 am
The Analogy of Lichens and Mosses
Paul Wilson
Mosses and lichens have some serious ecophysiological similarities, but they are not particularly related on the tree of life.
Both mosses and lichens are photosynthetic, making their livelihood from the rays of the sun when wet, and both are able to tolerate drying out completely. Their costs from drying out and then being re-wetted are minor in general, although it varies from species to species in both groups. Both groups pretty much lack vasculature, lack roots in particular, and so they are not drawing their water and nutrients from underground. They live on surfaces. They have modest nutrient demands, met by deposition from the air, from water flowing over their bodies, or from wicking up solutions that collect on their substrates. In both groups, various species have arisen that do well on trees, on rocks, and on bare inorganic soils.
The bodies of mosses and lichens die and contribute to the organic matter of their little spots on the earth, thereby contributing to the formation of organic soils. While living, and actually for a while after death, both mosses and lichens hold on to nutrients and water, smoothing out the downs and ups of ionic concentrations and moisture availability. Mosses and lichens occupy a very wide range of biomes, from the rainforests to the deserts, not the oceans and scarcely the lakes, but notably the streams. In deserts, they form the physical matrix of soil crusts that are then completed by the addition of microorganisms. Soil crusts are important in adding fixed nitrogen to the system, keeping the sand in place physically, and providing a selective sieve to the germination of various vascular plants. In the super wet ecosystems along the coast of the Pacific Northwest, mosses and lichens cover most surfaces, mosses more down-low and lichens a bit more up-high. These medium-sized photosynthesizers are responsible for a big part of the productivity of the forests, even though they are consuming only the light flecks that have gotten through the boughs of the more dominant vascular plants.
The similarity of the adaptive zones and ecosystem consequences of mosses to lichens is ‘only’ an analogy, not an inheritance from the ancestors that they had in common. A moss is a plant by any definition. Its multicellular complexity is akin to that of a vascular plant, and mosses are a large branch of the land-plant tree. A lichen is made of a fungal component and an algal component. The fungus is more closely related to animals than to plants. A lichen is a plant only in the sense that it is a photosynthesizer. The common ancestor of a lichenized fungus and a moss was unicellular and about as remote as any ancestor that was shared in common between any two complex multicellular organisms. It is the same as the most recent common ancestor of an oak tree and a human.
Out in the Universe, there are other planets with temperature and chemical regimes like Earth’s, places where it rains fresh water. On some of those other planets, life has presumably arisen and spun off complex medium-sized organisms and on some of those planets something like a moss or a lichen has radiated into a delightful array of species that can photosynthesize when wet and become dormant when dry. So you see: mosses and lichens are analogs.