Wildfire effects on lichens have recently been coming to the attention of biologists and foresters who are studying the long term effects of the very hot fires that have become more common in the North American west. The forests developed over thousands of years to withstand and benefit from low intensity, frequent fires. We humans suppressed the fires for over 100 years, and now the increasing but historically normal dry conditions and build up of unburned woody material in the forests, as well as the vast number of beetle-killed trees create conditions that encourage fires to start and burn hotter than normal.
These super hot fires burn the forest more completely, killing all the lichens. Many years later there are no signs of lichens in the burned areas. Scientists suspect the lichens will not return until the forests grow large, older trees that provide habitat for lichens. The lack of lichens in a new forest will affect the health of the trees, and the ability of many animals and insects and birds to live in a burned over area. Many species depend on lichens for some aspect of their lives; without lichens, these residents disappear.
When we see the diversity and quantity of lichens in an established forest, it becomes clear they are an important part of the community. After a fire, and also after human logging activity forests do regrow, but we are only starting to understand some of the ways each member of the forest plays an essential role in making a resilient, vibrant, and sustainable environment that all life can depend on. We are starting to realize that some trees and other plants growing after a fire are only a small part of the life that needs to become established and begin cooperating to make a real forest. Maybe in the future we will change our management habits to not suppress natural processes, and when we do interfere, we will use more comprehensive methods to renew the forest, such as inoculate with lichen spores as we plant trees, consider helping other plants grow, and diversify the species we plant. We’ll also need to choose trees, forbes, lichens and maybe even soil microbes that fit the environment being addressed.
We’ll need to think about the combinations and timing of introducing species. Just sticking some pine trees into the ground is not in any sense ‘reforestation’. (I planted trees for paper companies for years and was rudely awakened by what passed for ‘reforestation’.)
While we contemplate these ideas, we also have to learn at what stage of a forest’s growth each member of the community enters and establishes itself. We know in general, but I am sure we have a lot to learn. We know lichens are one of the first to colonize new earth, then moss, liverworts, ferns and on to larger plants. Each species, each facet of rock, wood or soil has special properties; they combine and change in minute but critical ways, in an elaborate dance with each other.
Maybe one of the good things to come out of the tragic fires in the western forests will be a desire to regrow forests that are resilient and adaptable as well as useful for our timber needs.
NOTE: Identification of lichens in these photos is tentative. If anyone reading this site has a suggestion for a more accurate identification, please contact me. Thanks!
Here in Lichen Land, the tiny but vast community of lichens, bryophytes and fungi are having a party on the Wintergreen Trail. Cladonia and Peltigera, Stereocaulon and Candelariella, Xanthoparmelia and a small crowd of their crustose friends are sporting fancy apothecia (disc or cup that produces spores) in many shapes and colors. The place is decorated in the brightest colors-turquoise, jade green, yellow, white, black, gray, brown, rust, pale blue. A Cladonia first caught my eye; she was fringed and spangled with intricate weavings of pale green, crowned with a russet apothecia/cap perched on her tall slender podetia (stalk). Many other Cladonias waved jade colored cups, some fringed and some smooth edged. The Peltigera rufescens, that not long ago sported velvety gray thallus and dramatic, hooded, vase-like apothecia, now were a bit faded in places. But some of them had grown dozens of tiny, white rhizines (root like structures) from the underside of the thallus (the vegetative part of a lichen that contains the photobiant and mycobiont.
All this elaborate activity goes on within one inch of the ground. A wrong step by a human would destroy many years of growth. But you can join the party; pack a 6x or 10x hand lens, your camera, and just walk into Lichen Site 4. They’ll all be there. Once you step down the two stone steps and turn right, slow down. Stop. Take out the hand lens. Breathe and relax. Even though it’s a party down there, we need to slow down to join up with the Tiny Ones.
Have you ever hunted for 4-leaf clovers? Use the same type of gaze and attitude; you’ll be more successful with lichens because there are so many of them, you can’t miss them. Once a few are seen on the pine needle covered ground you will start to see the stalk-like podetia everywhere. Get down close to them, use your hand lens held close to your eye, then move closer or farther from the lichen to focus, keeping the lens close to your eye.
At ground level the elaborate, fringed structures make a fairyland scene. A few weeks ago, the podetia were straight and smooth pointed stalks. Now they sport cups, caps and fringes. The thallus (the leafy part) may have rhizines, brighter color and also more elaborate shapes. There are many very tiny lichen growing among the taller ones so be careful where you step! It truly is a forest in miniature, with a canopy, mid layer and ground layer of plants and animals.
There are several types and species of lichen sharing Cladonia’s forest. Peltigera sp. has been introduced earlier, but there are many more lichen here. On the edge of the narrow pathway, rocks with lichens barely discernible in the summer now are alive with color and texture. These are crustose lichens, and there are quite a few species here. Many
species of crustose lichen on the rocks at this site have produced apothecia. Look for dark spots in the light colored crustose lichen body. Most of the lichen on these rocks are white, gray, or blue-gray. There also are some black crustose lichen here. Look closely with your hand lens to check for apothecia on the black lichen; they are hard to see. How many different species of lichen can you find? These can be very hard to identify without a high powered microscope to see details, and chemicals to test certain reactions lichens may have. At this time, the Lichen Hunters are simply recognizing these are ‘crustose’ forms.
On the low, sandy cliff (the cliff is 2-3 feet high) at the top of this area, the walls have been decorated in turquoise, green and white. The colors are bright and clear. In the shadows under the rocky overhang, the gauzy, lacy texture of lichen mixed with moss, spider webs and falling grains of sand make a confusing scene. What is lichen, and what is sand grains, or spider webs?
As the sunbeams illuminated strands of turquoise and green against the dark recesses it seemed to be an endless mass of tangled threads. Much of the lichen here is probably a Stereocaulon sp. commonly called ‘Rock Foam’. There are several species, some of which, in the arctic, are food for caribou during famine.
Pixie Foam, a miniature Stereocaulon species, often grows where there is a high concentration of metals in the rock. Lichens are used all over the world to prospect for minerals by analyzing the mineral content of the lichen thallus. (From ‘Lichens of the North Woods).
How many species of lichens can you sort out, under the sandy ledge? There are also mosses, ferns and fungi here. How many different life forms can you find, of any kind? This is a rich, active place, yet we know almost nothing about the lives here, or what their place in the world might be.
This visit to Lichen Land left me feeling as if I’d crashed a party. The last time I was here, the lichen were growing podetia but were much smaller. Today I crossed the threshold of two stone steps into their world, and it had changed dramatically. Colors were brilliant, forms were elaborate; the lichens seemed more alive! They didn’t seem like the same lichens I’d seen earlier. It was quiet, but I felt there was music and shouting and dancing going on, in a tiny way. It felt like a party.
As I walked away I thought about how the earth, rock, sand, and trees, each have a community of lichen. They are not plants, they are not animals; they are simply something else. What do they weave for the web of life in the world as we know it? Why do they cover such a large part of the earth’s land surface? There are over a hundred species of lichens on the base of the trees in the Kickapoo Valley Reserve. We don’t know how many different ones are in the canopy, or the soil or on the rocks here. Everything in Nature has a place and a purpose. The Lichen Hunters are exploring what that might be for the lichens in the Kickapoo. Come on out for a walk in the woods and help us learn about the Tiny Ones.
Did you know that many, maybe most lichens have some antibiotic properties? Animals and birds know this and eat or use lichens in various ways that may help them stay healthy. One common use of lichens is as a construction material in bird nests. The lichens may help keep baby birds disease free. Many birds use lichens, so look for nests especially when the leaves fall off the trees in autumn and nests are easier to find, and notice how many may have some lichens incorporated. If you can figure out what species of bird made the nest, that’s even better. Please let the Lichen Hunters know of your find.
It is not for us to know all the reasons a blue -gray gnatcatcher builds its home with lichens, but I can think of several possible reasons. Of course one reason is the known antibiotic property of the lichen; a built in disinfectant, in the walls of this perfect little home! Another reason may be that lichens are beautiful; the lovely blue-gray color the gnatcatcher likes in the lichens can be found in elegant home decor magazines, for human homes. Maybe the blue-gray gnatcatcher is matching its own color by using the same color of lichen on its nest walls, as we would wear harmonious colors because they are pleasing to see. Another reason may be that the flat surface of the foliose lichen may be somewhat water resistant and makes a nice solid surface. Also, since the lichens grow on the tree branches, covering the nest with the same lichen is good camouflage, hiding the chicks who would be a tasty treat for many predators, as well as the adult birds when they are resting on the nest.
Years ago I found a hummingbird nest made of lichens, in an apple tree. The nest was the size of a thimble. I considered it a small miracle that branch appeared right in front of me while picking apples.
This lovely photograph is from Paul and Bernadette Hayes. They recently found the nest about 10 feet up in a box elder tree, on a horizontal branch. It is the home of a bluegray gnatcatcher. Thank you Paul and Bernadette.
Discovering a well made birds nest covered in lichen is a lucky find. Please share your discoveries so we can learn about the birds in our home territory that use lichens.
Today a friend and I walked to the top of Black Hawk rock. A light snow still covered shady areas, the sun was low in the sky and gray-blue clouds scattered into the distance. There was no wind, no birds singing. A flock of turkeys walked across the ridge above us making clucky noises. As we climbed up the west side of the hill, the colors of tree trunks, fallen leaves, and rocks seemed to get brighter and brighter. Greens, blues, white, yellow. Lichens! If they could sing, they probably would be doing a hallelujah chorus today. Everything is saturated from many days of rain and light snow, and the temperatures have been above or near freezing, and nothing else is growing to block the light. The Little Ones are feeling good! The forest is full of living, growing plants in the middle of winter. They are all very tiny and all they need is moisture, light and above freezing temperatures to flourish while all other plants and most animals are dormant.
Green and blue lichen covered pieces of bark scattered on the ground from a fallen branch.
Part way up the hill a tree trunk was lined with white stripes. From smooth white layers to toothed patches this fungus (possibly Irpex lacteus) changed shape and finally supported small white fungus with purple red undersides.
Moss, liverworts and lichens crowded branches and then rocks as we climbed onto the top of the ridge.
At the top we stand on the rocky point and the whole Kickapoo valley falls away into the distance; to the east, south and west. The sun breaks through clouds illuminating the far reaches of the valley and fallow fields turned golden. Juniper and oak cling to bare rock here and the lichen cling to the trees and rock. Every living thing is attached to another living thing. Snow and lichen share the rough branches. Some of the lichen are frozen solid but close to them others are soft and flexible. The cup shaped lichen are frozen solid, the liverworts, moss and flat green lichen are not, in the picture below.
The rock at the top of the cliff feels many footsteps over time but lichen are everywhere here. Gray, yellow, orange, blue, green, purple, white; the rock looks painted with lichens. We look down across the valley and realize that much of the color we see in the landscape is the color of the lichen and mosses that are an essential part of the system of lives that make our world alive. The white and pale green colors of branches in the treetops are lichen; the yellow, gold, green and black of rock faces are lichens, and their companions the moss and liverworts.
We ended the day walking through a field of big bluestem and other prairie plants, now golden and coppery in the sun. We know tomorrow the Little Ones will be frozen and dormant under the coming snowstorm; but as soon as the sun touches them again they will come back to life.
PS: My attempts to name species is open for corrections and suggestions. We are working on learning to identify lichen (and fungi and moss) so at this time are making guesses at best. If you know what a lichen or plant is in one of these pictures, please let us know what you think.