Spore bearing plants evolved a long time before seed-bearing plants, and have developed a variety of complex reproduction strategies. Each plant produces billions and billions of spores! However, less than 1% of these spores survive! This is mainly because the spores dry out before they get to a place that has the right conditions for them to germinate. If the billions of spores ALL germinated, the earth would be covered in spore-bearing plants! Locally, there are several kinds of spore bearing plants that are currently thriving in the cool winter rains, including mushrooms, lichen, moss, and evergreen ferns. Unlike seed-bearing or flowering plants, these plants don't have flowers and don't need insects to pollinate them. Winter is the time for them to thrive as they all need rain for their spores to be produced. The more I read about them, the more complex they become! So bear with me, it's a lot of information! I find it super interesting, but I just read it to my husband and he dozed off! Not a good sign!
Questionable Strophuria - Strophuria ambigua
Mushrooms!
Due to the recent rain and slightly warmer temperatures, mushrooms (Basidiomycetes) have started popping up in our neighborhood.
This type of fungi is either parasitic, saprophytic, and/or mycorrhizal.
Parasitic fungi feed on living organisms, usually trees. Saprophytic fungi live on dead organic matter, and break it down into simpler, reusable compounds. Mycorrhizal fungi are underground fungal filaments that connect with the roots of trees and form a mutual relationship between them. The tree benefits because the fungi filters out heavy metals and protects the tree from bacteria and detrimental fungi. In return, the fungi get sugars and carbohydrates from the host tree.
The main part of a mushroom is a web of fine white threads called mycelium, usually found underground. The individual threads are called hyphae. This is the part of the mushroom that digests nutrients and can also create a mycorrhizal relationship with trees. Additionally, when a male hyphae and a female hyphae meet underground, they fuse together and produce a mushroom. Mushrooms are the fruiting bodies of the mycelium.
To reproduce, mushrooms produce spores. Basidia are the microscopic, club-shaped, spore-bearing structures in mushrooms. There are three main structures in mushrooms that contain the basidia; gills, pores and teeth! Most people are familiar with the gill structure pictured above left. Pores are found on Bolete fungi and others, and are the small holes (actually tubes) on the smooth underside of the mushroom cap. Teeth are found on Lion's Mane fungi as well as others, and look like tiny hanging icicles. Thousands and thousands of basidia are arranged along the outside edges of the gills, the insides of the tubes that end in pores, and on the outside of the teeth!
A variety of critters are fungivores (eaters of fungi), such as the Northern Flying Squirrel, deer, mice, voles, squirrels, and even banana slugs! I recommend that you DON'T eat them unless a mycologist has identified them for you. Some of them can be deadly if you eat them. I've only seen a couple dozen mushrooms so far, but I'm sure more will be popping up soon. I'll keep you posted on what I find.
Crustose Lichen and dried Bracken Fern
Lichens!
Lichen (Ascomycetes), like moss, is a non-flowering plant, that has no roots or vascular system, has several methods of reproduction, and is dormant during the hot and dry summer. Lichen is a combination of a fungus and an algae or cyanobacteria, living together in a symbiotic relationship! The fungus cannot photosynthesize like moss, as it has no chlorophyll, but the algae can. The fungus forms the external shape, or thallus, of the lichen, and keeps the algae from drying out. It also supplies the algae with water and minerals that it absorbs from the atmosphere. In return, the fungus lives off the sugars produced by the photosynthesis of the algae! There are about 17,000 species of lichen worldwide!
There are three main forms that lichens are grouped in, crustose, fruticose, and foliose. Crustose lichens (above) grow on rocks and are more or less flat. They can come in a wide variety of colors including, apple green, rust, orange, yellow, black, white and gray. They are extremely slow-growing and long-lived! It's estimated that some of the crustose lichens found in the Arctic are approximately 8,600 years old!
Foliose lichen usually grows on tree bark or rocks, and is distinguished by its "leafy" appearance. I think it looks like lettuce!
The fruticose lichen usually grows on shrubs and trees. It is multi-branched, and can be found growing either upright or hanging down. Fruticose and foliose lichens are slow growing like crustose lichen, but may only be a few hundred or a thousand years old.
Like mosses, lichens reproduce in a variety of ways. They can sexually reproduce with spores that are found on their apothecium (the brown shapes in the above photo). However, these spores will only reproduce the fungus, not the algae. This newly made fungus will have to somehow connect with the right algae to form a new lichen plant. Lichen can also reproduce vegetatively from pieces of its thallus, through soredia (clusters of algae cells wrapped in fungal filaments), or through isidia (miniature lichens, including algal cells, that grow on the top of the thallus).
Membranous Pelt Lichen - Peltigera membranacea
The Membranous Pelt Lichen is leafy with BIG leaves, and seems to mainly grow in among mosses. It's grayish, blue-green color indicates that it has mainly cyanobacteria in the leaves, rather than mostly algae. Cyanobacteria can make amino acids from nitrogen gas absorbed from the air!
Membranous Pelt Lichen apothecium and underside of leaf with rhizines
Peltigera membranacea
The apothecium (spore-bearing structure) of the Membranous Pelt Lichen is somewhat cup-shaped, like most Ascomycetes or Cup Fungi. On the underside of its leaves it has lots of spiky-looking rhizines, that help attach it to a substrate.
©https://cloudfront.net/images
As in mosses, Tardigrades/Water Bears/Moss Piglets inhabit lichens! I discussed these fascinating creatures in my blog on "Moss in Winter", Nov. 21, 2020. I have since looked for them in lichen and I FOUND SOME! I also re-looked at moss and found some Tardigrades in them as well!! WOW! So cool to see, but WAY too tiny to photograph! The best way to find them is to not initially focus too close with your microscope. Look at the water that was lightly squeezed from the moss or lichen, at the lowest power of your microscope. Watch for movement. Then power up to zoom in close on the movement! When you are done observing them, make sure you return the lichen or moss, and tardigrades, back outside where you found them!
Haircap Moss - Polytrichum sp.
Mosses!
Mosses are also spore-bearing plants! My blog on "Moss in Winter", Nov. 21, 2020 thoroughly discusses mosses and their multi-faceted existence! Please check it out! Featured in these photos is Haircap Moss and its sporophytes (spore-bearing structures).
Haircap Moss sporophytes - Polytrichum sp.
Haircap Moss is the second most common moss in my neighborhood,
Dendroalsia Moss (Dendroalsia abeitina) being the most common.
Imbricated Sword Ferns - Polystichum imbicans
Some ferns can survive the freezing temperatures of winter, and some can't. Those that stay green, reduce the water and increase the sucrose in their cells. This acts like an anti-freeze and lowers the temperature at which water freezes, thus preventing the formation of ice crystals and subsequent damage to the plant cells. This is the same winter strategy as moss, and evergreen trees/shrubs.
Imbricated Sword Fern sori - young fern fronds
Polystichum imbicans
Ferns reproduce by producing spores. Spores are encased in structures called sporangia, which sometimes clump together to form a sorus (plural sori). Right now some of the ferns have sori and some don't.
The life cycle of a fern is QUITE complex! The following information is from the website https://www.thoughtco.com/fern-life-cycle-4158558 .
"The fern life cycle requires two generations of plants to complete itself. This is called alternation of generations.
One generation is diploid, meaning it carries two identical sets of chromosomes in each cell or the full genetic complement (like a human cell). The leafy fern with spores is part of the diploid generation, called the sporophyte.
A fern's spores don't grow into a leafy sporophyte. They aren't like seeds of flowering plants. Instead, they produce a haploid generation. In a haploid plant, each cell contains one set of chromosomes or half the genetic complement (like a human sperm or egg cell). This version of the plant looks like a little heart-shaped plantlet. It is called the prothallus or gametophyte. Within the gametophyte, sperm is produced within a structure called an antheridium. The egg is produced within a similar structure called an archegonium. (the same structures as in moss!)
When water is present, sperm use their flagella to swim to an egg and fertilize it. The fertilized egg remains attached to the prothallus. The egg grows into the diploid sporophyte, completing the life cycle."
Phew! Now that was complex enough!
Weather Update!
We had some wet and windy days this week, with a total rainfall of 1.86"!!!
This week coming up is supposed to be sunny. Hopefully more rain will come again soon!
What's happening in the Lakes Basin?
What about those deer?
Are there any insects around?
Check back next week for the answers to these questions and more!
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