Flora Archives - Page 26 of 40

July 11, 2013December 1, 2023

Lichens

Click for a larger view of Rosette Lichen, Courtesy and copyright 2013 Andrea Liberatore, Photographer — Boulder covered in a
variety of lichen species
Copyright 2013
Andrea Liberatore, Photographer
Rosette Lichen
*Physcia dubia*
Lives in both Antarctica
and the Mojave Desert
Copyright 2013
Andrea Liberatore, Photographer
Rim Lichen
*Lecanora muralis*
Has anti-cancer and
anti-microbial properties
Copyright 2013
Andrea Liberatore, Photographer
Garovagis Rim Lichen
*Leconara garovagii*
Used in perfume & sunscreen
Copyright 2013
Andrea Liberatore, Photographer

This spring I visited Red Butte Gardens in Salt Lake City for the first time. My favorite part was a small and very non-descript garden, tucked alongside a walkway and devoted to an organism that isn’t a plant at all, but instead a very under-appreciated genera of life – the lichen.

Lichens are those colorful crusts found growing on rocks and trees, and while sometimes plant-like in appearance, they are not plants. Lichens have no leaves, stems, roots, or vascular systems. Even more strange, lichens are not a single organism, but instead a partnership between two organisms: a fungus and an algae or cyanobacteria. Because the fungus is generally the dominant partner, lichens are classified as members of the Fungus kingdom.

The partnership exhibited by these two organisms is an example of mutualism – a relationship where both parties benefit in some way through their interaction. In this case, the fungus provides a safe and secure home for the alga or cyanobacteria, which in return photosynthesizes and provides the fungus with nutrients. Cyanobacteria and algae are typically found in water and are prone to drying when exposed to sun and wind. The fungal partner provides shade and protection from desiccation by sheltering the algae within its body. As a result, lichens are incredibly drought-resistant and can be found in a wide variety of habitats including some of the most extreme environments Earth has to offer. In fact the Rosette Lichen or Physica dubia grows in both Antarctica and the Mojave Desert!

Lichens are not just interesting from a biological perspective, but also a chemical one. Lots of lichens create and exude a suite of chemicals, the roles of which aren’t entirely known. Some are thought make the lichen distasteful to predators, while others may help block harmful UV rays and increase membrane permeability to facilitate the movement of nutrients, water, and cellular byproducts between algae and fungi.

These chemicals have also attracted the attention of scientists, as some exhibit antimicrobial, antiviral, anti-tumor, and insecticidal properties. Many are being analyzed and tested for a variety of medicinal and household uses and may soon become a key ingredient in a physician’s arsenal. Already, these organisms are utilized by humans in a number of different ways, and have been for hundreds of years.

In some native cultures around the globe, lichens are a part of the traditional diet for both people and livestock. However, most lichens have little nutritional value, are bitter tasting, and some can be toxic. Lichen extracts are also used as natural dyes for wool and cloth with colors ranging from browns and purples, to yellows and oranges. Other uses include the manufacture of perfume, cosmetics and sunscreen, a substitute for hops in brewing beer, and as a key ingredient in litmus paper.

Lichens are also sensitive to air pollution, and for that reason don’t typically grow too close to human habitation. In fact, lichens absorb pollutants into their tissues and for that reason can play an important role as an indicator species for pollution problems. As air pollution becomes more widespread, lichen species could be in danger of being lost. And because we have only scratched the surface of what these amazing organisms can do, who knows what future medicine could be lost along with it.

I could go on, as I have only scratched the surface of what these organisms can do. And in the coming years, I think we’ll hear of even more lichen-based breakthroughs in science and medicine. The next time you pass a colorful, lichen-covered rock, take a closer look at these incredible organisms and pause for a moment to wonder about the mysteries, and possible answers, that lie within.

For the Stokes Nature Center and Wild About Utah, this is Andrea Liberatore.

Credits:

Photos: Courtesy & © Andrea Liberatore
Text: Andrea Liberatore, Stokes Nature Center, logannature.org

Additional Reading:

Ivins, Robert Fogel (1998) Lichens are Fungi! Utah State University Herbarium. Available online at: https://herbarium.usu.edu/fungi/funfacts/lichens.htm

Center for Ecological Sciences, Indian Institute of Science. Lichen Chemistry. Sahyadri E-news. Issue 34. Formerly available online at: https://wgbis.ces.iisc.ernet.in/biodiversity/sahyadri_enews/newsletter/issue34/lichens_chemistry/lichen_chemistry.pdf See https://www.researchgate.net/publication/257213745_Sahyadri_Shilapushpa_Lichen_Chemistry [Link updated Dec 1, 2023]

US Forest Service (2013) Celebrating Wildflowers: Lichens. Available online at: https://www.fs.fed.us/wildflowers/interesting/lichens/

May 23, 2013March 1, 2018

Amazing Adaptations of Utah’s Desert Plants

Hi, this is Mark Larese-Casanova from the Utah Master Naturalist Program at Utah State University Extension.

Anyone who lives in Utah knows that it’s a dry state. In fact, around three-quarters of our state is considered desert. A desert is often characterized as an area that receives less than ten inches of precipitation each year. But, high levels of evaporation, which are influenced by temperature, wind speed, and solar radiation, also contribute to creating a dry desert ecosystem.

So, how exactly are plants able to survive in Utah’s deserts, which are so dry? It turns out that the plants that grow and flourish in Utah’s deserts have an amazing array of adaptations for survival.

Many shrubs and trees, such as desert willow, and certain species of sagebrush and mesquite, have thick taproots that grow deep into the soil to reach groundwater. This helps the plants survive the hot, dry summer. Some mesquite taproots have been found to grow as deep as 200 feet to reach a constant water supply.

Cacti, such as the various types of prickly pear, have almost an opposite adaptation. They produce dense tufts of fibrous roots just below the surface of the soil. This allows cacti to quickly absorb water from brief rainstorms, and then store the water in their thick, succulent leaves.

As temperature increases, desert plants face the danger of excessive water loss from their leaves. A thick, waxy coating on the outside of leaves often helps to retain water. The shiny wax also reflects sunlight to keep the leaves relatively cooler. To further reduce leaf temperature and water loss, some plants, such as brittlebush, grow light-colored dense ‘hairs’ on their leaves and stems. These trichomes not only shade the plant, but also aid in absorbing water from morning dew.

If temperatures get too hot, and drought stress too great, some plants, such as creosote bush and ocotillo, may drop their leaves several times each year to ensure survival. Some of these plants have green chlorophyll in their stems so they can still produce food through photosynthesis when there are no leaves on the plant.

While this is just a sample of an amazing collection of adaptations, it’s clear that desert plants are champions of survival in a harsh ecosystem where water is so scarce.

For Wild About Utah, I’m Mark Larese-Casanova.

Credits:

Images: Courtesy & Copyright Mark Larese-Casanova
US FWS images.fws.gov
Text: Mark Larese-Casanova, Utah Master Naturalist Program at Utah State University Extension.
Additional Reading:

Utah’s Desert Dwellers: Living in a Land of Climate Extremes. Wildlife Review. Utah Division of Wildlife Resources
wildlife.utah.gov/wr/0706desert/0706desert.pdf

Deserts. James MacMahon. The Audubon Society Nature guides. 1985. https://www.amazon.com/Deserts-National-Audubon-Society-Nature/dp/0394731395

Natural History of the Colorado Plateau and Great Basin, Harper, St. Clair, Thorne, and Hess (Eds.), 1994. https://www.amazon.com/Natural-History-Colorado-Plateau-Great/dp/0870815113

The Biology of Deserts, David Ward, Oxford University Press, 2009. https://www.amazon.com/Biology-Deserts-Habitats/dp/0199211477

May 16, 2013June 27, 2016

Dyer’s Woad

In early May, pale yellow carpets some hillsides of Northern Utah. The plants are a non-native known as Dyer’s Woad. This Asian member of the cabbage family has been cultivated as a dye and medicinal plant in Europe and Asia for 2000 years. Dyer’s Woad produces a glorious blue dye, but the process is tricky. No synthetic dye equals the color and characteristics of woad dyes.

Woad had arrived in Utah by 1932 as a seed contaminant. Now it is a noxious weed. Woad has a number of unique abilities that contribute to its vigor. Being a biennial plant, it spends the first year of life as a rosette of leaves, building reserves. In its second year, those reserves allow a woad plant to send forth a tall, lanky stem covered with pale yellow flowers that ultimately yield up to 10,000 seeds per plant.

Although Dyer’s Woad is not toxic, few animals relish it either. The seeds have chemicals that inhibit germination and root elongation in other plants, giving woad a competitive edge. Woad causes millions of dollars in losses each year, so control is a major issue. Herbicides and mechanical removal are best used against the rosettes, but nature has provided a native fungus that views woad as dinner. This rust fungus is very effective at eliminating or severely reducing seed production. Plants infected with the rust fungus are misshapen, wrinkly, and covered in dark spots. Those spots brim with rust spores. Therefore, when removing woad, leave the sickly plants to infect yet more woads.

Click to view a larger picture; Dyer's Woad with rust courtesy and copyright 2009 Brad Kropp - as found on bugwood.org — Dyer’s Woad with rust
Courtesy of and
Copyright © 2009 Brad Kropp
As found on bugwood.org

This is Linda Kervin for Bridgerland Audubon Society.
Credits:
Photos: Brad Krupp, Utah State University, Bugwood.org
Text: Michael Piep, Utah Native Plant Society

Additional Reading:

Resources:
Intermountain Herbarium: https://herbarium.usu.edu/

Washington Weed Board: https://www.nwcb.wa.gov/weed_info/Written_findings

/Isatis_tinctoria.html

References:
Edmonds, J. 2006. The History of Woad and the Medieval Woad Vat. https://www.lulu.com/product/paperback/the-history-of-woad-and-the-medieval-woad-vat/4928037

Shaw, R.J. 1989. Vascular Plants of Northern Utah. Utah State University Press, Logan, Utah. https://www.usu.edu/usupress/books/index.cfm?isbn=1417

Welsh, S.L., N D. Atwood, S Goodrich & L.C. Higgins. 2008. A Utah Flora, 4th Ed. Brigham Young University, Provo, Utah. https://www.amazon.com/Utah-Flora-Stanley-L-Welsh/dp/0842525564

April 25, 2013June 27, 2016

Cryptobiotic Soil Crusts

Click to view larger image of Cryptobiotic Soil Crust, Photo Courtesy and Copyright Mark Larese-Casanova — Cryptobiotic Soil Crust
Photo Courtesy & Copyright 2009
Mark Larese-Casanova

Hi, this is Mark Larese-Casanova from the Utah Master Naturalist Program at Utah State University Extension.

Looking out over a Utah desert, we might see relatively few plants- perhaps some sagebrush, maybe a few junipers or Joshua trees, or even some small wildflowers or cacti. What is less noticeable, though, is the living soil crust that holds this entire landscape together. It’s not just sand, but rather an important and vast partnership between bacteria, lichens, algae, and fungi. These soil crusts are often referred to as ‘cryptobiotic’, which means ‘living in suspended animation’. This is a fitting description, considering that water can be so rare in Utah’s deserts.

Cyanobacteria, which is often called blue-green algae, is the backbone of cryptobiotic soil crust. Vast networks of long, microscopic filaments of cyanobacteria and fungi grow in length when they are wet, and leave behind a casing that literally binds the soil together. So, what might otherwise be loose sand not only is less likely to be washed away by water or blown away by wind, but also is able to hold much more water for plants.

Cyanobacteria is also extremely useful to desert landscapes for its ability to take Nitrogen out of the air and make it available to plant roots in the soil. Desert soils typically have relatively low nutrients, so this is especially important to desert plants.

In many Utah deserts, cryptobiotic soil crusts can cover up to 70% of the ground surface. Old soil crust can often look like small mountain ranges with black or white peaks inhabited by lichens or mosses. The little valleys in between the tiny mountains of crust are perfect spots for the seeds of desert plants to grow. Over time, the above ground crust can grow up to ten centimeters, or four inches, thick!

However, cryptobiotic soil crust grows at an alarmingly slow rate of about one millimeter per year. So, any soil crust that is disturbed can take a very long time to recover. Depending on the amount of moisture a desert receives, it can take anywhere between 20 and 250 years for soil crust to grow back.

Next time you’re out in the desert, kneel down and have a close look at the telltale peaks and valleys of cryptobiotic soil crust. If you bring a magnifying glass, you just might be able to see some of the lichens and mosses. Be sure to stay on trail, though, and whatever you do, don’t bust that crust!

For Wild About Utah, I’m Mark Larese-Casanova.

Credits:

Images: Courtesy and copyright Mark Larese-Casanova
Text: Mark Larese-Casanova, Utah Master Naturalist Program at Utah State University Extension.
Additional Reading:

US Department of Interior. 2001. Biological Soil Crusts: Ecology and Management. Bureau of Land Management Technical Reference 1730-2., https://www.blm.gov/nstc/library/pdf/CrustManual.pdf
Rosentreter, R., M. Bowker, and J. Belnap. 2007. A Field Guide to Biological Soil Crusts of Western U.S. Drylands. U.S. Government Printing Office, Denver, Colorado., https://www.soilcrust.org/