Bellingham, WA
Pacific Northwest
October/November, 2021
In our part of the world with our frequent rain and cloudy days, moss is everywhere. Old timers here are often referred to as “Moss Backs.” Moss grows most everywhere in the world, including in deserts and in Antarctica, everywhere but in salt water. Here in the Pacific Northwest it is special and omnipresent. Unless Istay inside and don’t look out the windows, I see moss everyday of the year.
The more closely I look at the various mosses, the more individual and unique they become. No longer are they just fuzzy, soft green growths that were cool unless they built up on one’s roof. Each has its own characters and defining features. They are not green blobs.
As I was collecting photos and information for this post I ran across a marvelous little book, Gathering Moss by a well known bryologist, Robin Wall Kimmerer. I have always loved moss, but after reading this book, I appreciate it even more. It’s really cool stuff.
Kimmerer’s book has many gems in it but a major point she makes about moss is that we generally miss so much of it as we stride over and past it, seeing a field of soft green without actually seeing it for what it is.
From her book:
Mosses and other small beings issue an invitation to dwell for a time right at the limits of ordinary perception. All it requires of us is attentiveness. Look in a certain way and a whole new world can be revealed.
[…]
Learning to see mosses is more like listening than looking. A cursory glance will not do it. … The “moss” is many different mosses, of widely divergent forms. There are fronds like miniature ferns, wefts like ostrich plumes, and shifting tufts like the silky hair of a baby.
Below I will illustrate these divergent forms that moss takes when we take the time to look closely with full attention to their uniqueness.
Moss is great in its own right but even better when it serves as a canvas to support and highlight other plants and organisms such as ferns, lichen and fungi. In addition to its own unique features it is the ultimate backdrop for highlighting the the other components that make up a forest.
What is moss?
Moss is an ancient plant type, perhaps the first plant to grow on land? This evolutionary transition from water to land is thought to have occurred about 350 Million years ago, probably from simple forms of green algae. Interestingly, it still requires water for fertilization. I have seen various estimates of the number of moss species ranging from 12,000 to 20 000. In either case there appears to be enough to soften the trees and forest floors among other things such as sidewalks and roofs.
Moss is a very simple plant as it does not have a vascular system as do most plants for water and nutrient transport. Neither does it have roots with which to absorb nutrients and water from its substrate. Rather it has root-like structures (rhizoids) that attach to substrates to secure it in place from where it traps water in its leaves which mostly are only one cell thick. Similarly it traps nutrients in its leaves. Like most other plants moss synthesizes carbohydrates via its leaves through photosynthesis.
Sexual reproduction:
The following schematic of basic moss sexual reproduction illustrates some of the basic components of moss plants that you will recognize in later photos.
Male and female gametophytes grow from buds on protonema, which develop from the spores put out by female sporophytes and its stem which have been fertilized by the male gametophyte’s sperm cell) from the antheridia. The sperm cell must be transported by water to the female gametophyte’s archegonia. From there the female grows a sporophyte which includes the upper part of the stem (seta) which grows with a capsule where the fertile egg matures into spores that are ejected and form into buds to make more gametophytes.
Asexual reproduction is also possible in which tips of leaves of the gametophytes break off and with water and nutrients, grow into genetic clones to become gametophytes which can then reproduce. This a main mechanism for spread of mosses on sidewalks for example as someone’s shoe steps on a moss plant a pience is broken off and transported further along. Just add water and a bit of sunlight for photosynthesis and the moss is happy as a clam. No wonder it multiplies so profusely in the PNW.
Species prevalent in the PNW
Let’s look at some specific mosses that are common in my neck of the woods. I cannot guarantee the accuracy of all of these specie IDs since iNaturualist and Seek do not always know what it is nor do they agree with each other. Nor do they always agree with my 20 year old edition of “Plants of the Pacific Northwest Coast.” Online some of the more current sites list new and old taxonomies which further confuses matters. I’ve tried to trace the latest taxonomic classifications but I am not a bryologist. Please jump in if you have other ideas on the identities of these little fuzzy greens.
The moss species that I show below are a selection chosen to illustrate some of the individual characteristics that define them.
Neckera is a large genus with several species plastered everywhere around the PNW as well as elsewhere in the world.
One prominent species in the PNW is Neckera douglasii. This is named after the naturalist, David Douglas who spent considerable time in the northwest in the 1820s and 1830s identifying, labeling and collecting numerous plant and tree species for the British Horticultural Society. One tree specie for which Douglas is most renown is the Douglas-fir that is so prominent here.
Neckera pennata (aka Shingle moss) is another local and cosmopolitan moss widely distributed around around the globe and abundant in my area. Although classified as ecologically secure on a global level, it is listed as imperiled in Washington State. Fortunately there seems to be plenty where I am.
Another moss species that I find throughout the environs that I traipse is the cat-tail moss (Isothecium myosuroides). It is very prevalent in temperate rain forests of the Pacific Northwest from Alaska to No. California. This moss is the one you often see draping from trees and limbs, logs or rocks in wet shaded forests.
Archibald Menzies’ Tree moss (Leucolepis acanthoneura) below was one of Menzies many plant namings from the early 1800s. He was was a contemporary and a mentor of David Douglas, who like Douglas has his name attached numerous plant species found in the Western US and Canada. It was Menzies who assigned Douglas’ name to the Douglas-fir. Menzies’ own name is found in the tree’s scientific name Pseudotsuga menziesii which he first described as botanist aboard Captain George Vancouver’s voyage of the HMS Discovery.
Moss as tiny critter habitat:
In addition to its uses as pot and hanging basket fillers and peat moss for mulch and fuel, moss also provides habitat for thousands of forest critters. For example, one gram of moss (size of a cupcake) plucked from a forest floor typically will produce the following: 150K protozoa, 132K tardigrades, (water bears and moss piglets), 3K springtails, 800 rotifers, 500 nematodes, 400 mites and 200 fly larva. Moss provides habitat for this myriad of critters complete with a compatible microclimate that retains water, nutrients and shelter for them to grow and reproduce.
When is a Moss not a moss?
Moss’s taxonomy is rapidly changing like other areas of the biological sciences due to the advances in genomics. Based on visual similarities, many look-a-like organisms were once given moss-related common names but are clearly not mosses at all.
For example, there is “Club Moss” (Lycopodiaceae), also called groundpine, which is a vascular plant more related to ferns than to moss.
Another very common “moss” that is not moss is “Oak Moss” that grows on oak and other trees and often falls off in little rosettes. It is a lichen which are cool in their own right.
And finally, here is one of my favorite photo collages of these critters. There are at least four clearly separate organisms ( two Mosses & two lichens, which are part fungi) on this trellis in my vegetable and herb garden. They seem to like each other’s company.
There you have a few of the hundreds (?) of moss species found in our yards and in the woods of the Pacific Northwest.
Share any moss adventures that you have had this fall as your area has gotten wetter with the fall rains. We just had record breaking rainfall here and I imagine that will result in record breaking moss proliferation. I can’t wait to see them puff up.