Audio:  mp3

Photo Courtesy NPS, Photographer:
Tom Heutte, USDA Forest Service,

A grassland inundated by cheatgrass
Photo Courtesy NPS
Neal Herbert, Photographer

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

It’s difficult to visit a landscape in the West without encountering cheatgrass. While cheatgrass’ small stature might make it hard to notice, it’s impossible to forget its sharp, spiny seeds. One hike through a cheatgrass meadow can render a good pair of socks unsalvageable.

Although cheatgrass, a nonnative grass scientifically known as Bromus tectorum, is an annual grass- germinating, growing, producing seeds, and dying each year- it is particularly effective at colonizing disturbed areas because it grows and produces seeds much earlier in the spring than many perennial native grasses. Cheatgrass monopolizes water and nutrients by germinating and establishing itself during the previous fall and winter, when many native plants have become dormant. Over time, cheatgrass has become the dominant ground cover in many of Utah’s sagebrush ecosystems.

The dense, dry, fine stalks of cheatgrass, which sets seeds and dries out by June, are particularly flammable fuel for wildfires. Fire roars through the carpet-like cover of cheatgrass, and wildfires are now at least twice as frequent as they were in the 1800’s. This has caused a loss of sagebrush habitat that is particularly important to a wide diversity of wildlife. More frequent fires create an even greater challenge for rare species such as the black-footed ferret and desert tortoise to survive. Native grasses are slower to recover from fire, and cheatgrass is particularly effective at recolonizing burned areas. Utah State University researchers Dr. Peter Adler and Aldo Compagnoni have found that reduced snowpack and warmer temperatures promote the growth of cheatgrass, which could potentially increase its distribution and fire risk into previously colder areas of Utah.

Researchers and managers are continually working to find ways to control cheatgrass in Utah. Effective control usually involves a combination of mechanical pulling or tilling, grazing, burning, spraying with a chemical herbicide, and replanting with native grasses. USU researchers Dr Eugene Schupp and his former graduate student Jan Summerhays found that applying a pre-emergent herbicide to prevent the germination of cheatgrass seeds, as well as temporarily limiting Nitrogen in the soil, gave native grasses and perennials a better chance of establishing. When faced with such a large management problem in Utah and throughout the West, we can use all of the helpful tools we can get.

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


Images: Courtesy NPS, Neal Herbert Photographers
and NPS, USDA Forest Service,, Tom Heutte Photographer
Text:     Mark Larese-Casanova, Utah Master Naturalist Program at Utah State University Extension.

Additional Reading:

Beck, George. Cheatgrass and Wildfire. Fact Sheet No. 6.310. Colorado State University Extension.

Cheatgrass. Range Plants of Utah.

Fairchild, John. Cheatgrass: threatening homes, stealing rangelands. Utah Division of Wildlife Resources.

Opsahl, Kevin. USU study: Climate shift could trigger cheatgrass. Herald Journal . October 21, 2012.

American Invasion

Audio:  mp3

Eurasian Collared Dove, Courtesy, Joy Viola, Northwestern University, Photographer

Eurasian Collared Dove
Streptopelia decaocto
Courtesy & ©
Joy Viola, Northwestern University, Photographer

Colorado Potato Bug, Courtesy, USDA ARS, PhotographerColorado Potato Beetle Adult
Leptinotarsa decemlineata
USDA ARS, Photographer

Hi, I’m Holly Strand from the Quinney College of Natural Resources at Utah State University.

More and more you are likely to hear this sound in Utah yards, parks and fields. [Eurasian Collared Dove, Courtesy Ryan O'Donnell,] That’s the call of the Eurasian collared dove. Originally from Asia, this dove has been expanding its territory around the world at an incredible rate. The first sighting in Utah was in Orem in 1997. And now the doves are everywhere. So far, it doesn’t look like our native mourning dove is affected. But such rapid population explosions rarely occur without some sort of undesirable ecological consequence.

In America, the Eurasian collared dove is an invasive species. But not all non-native species are invasive. “Invasive” only applies when species spread far beyond the area where they are first introduced. Luckily, not all invasive species turn out to be serious pests. Ecologist Mark Williamson suggested the tens rule. About 10% of introduced species establish lasting populations and 10% of those go on to become problems.

There’s a long list of Eurasian invasives in Utah. Among them is the highly flammable cheat grass that comes from southwestern Asia. Those massive clouds of starlings? They come from Europe. Tamarisk from Eurasian deserts lines the Colorado River and tributaries. The common carp is an unwelcome Eurasian colonist of our lakes and large rivers. And the American west’s iconic tumbleweed is an invader from the Russian steppe.

Why so many invaders from Eurasia? Well for the last 500 years, there has been a net outflow of Eurasians—especially Europeans—to other parts of the world. And this human population carried its biological baggage along with it—in the form of animals, plants and diseases. Some ecologists believe that the physical geography and human history of Eurasia has conditioned its species in such a way that they will consistently outcompete the species of other continents. But that’s debatable. For in the last decades the New World has started to lob some pretty competitive species over to Eurasia.

For example, the American mink was brought to the Eurasian continent in the 1920s for use on fur farms. But–because of deliberate releases and accidental escapes–the mink is now common in the European wild. And it’s a pest. The American mink is taking the place of the European mink which is now threatened with extinction. Furthermore, the American mink is gobbling up populations of many ground-nesting birds.

Unless you are involved in agriculture, you might not have heard of the Colorado potato beetle. But potato growers around the globe know this striped orange and brown beetle from the American southwest very well. It has a voracious appetite for potato leaves and quickly develops resistance to any chemicals used against it.

And a final example: the American bullfrog is considered one of the world’s most damaging invasives. The bullfrog does amazingly well in a variety of habitats –even artificial ones like millponds, irrigation ditches and reservoirs. Its incredible adaptability helps it spread and outcompete native frogs. Moreover, it has been transmitting a deadly fungus to previously unaffected populations of frogs, toads and salamanders.

Thanks to Lyle Bingham for information on the Eurasian collared dove. And to Ryan ODonnell for his audio recording from For more information on the Eurasian collared dove and other invasive species go to

For Wild About Utah, and the Quinney College of Natural Resouces, I’m Holly Strand.


1. Photographer Joy Viola, Northwestern University,
2. USDA ARS Photo Unit, USDA Agricultural Research Service, Bugwood.

Audio of Eurasian collared dove:
Ryan P. O’Donnell, XC98068. Accessible at
Creative Commons Attribution-NonCommercial-NoDerivs 2.5

Text: Stokes Nature Center: Holly Strand

Sources & Additional Reading:

Bingham, Lyle. 2009. The New Dove in the Neighborhood. Wild About Utah Program October 8, 2009.

di Castri F. 1989. History of biological invasions with special emphasis on the Old
World. In: Drake JA, Mooney HA, di CastriF, Groves RH, Kruger FJ, Rejma´nek
M, Williamson M, eds. Biological invasions: a global perspective. Chichester, UK:
John Wiley and Sons.

European Environment Agency, 2012. The impacts of invasive alien species in Europe EEA Technical report No. 16/2012. EEA, Copenhagen.

National Invasive Species Information Center (NISIC): Gateway to invasive species information; covering Federal, State, local, and international sources.

Simberloff, Daniel. 2013. Invasive Species: What Everyone Needs to Know. Oxford University Press

Sphinx Moths

Audio:  mp3

Big Poplar Sphinx
Pachysphinx occidentalis
Courtesy Whitney Cranshaw
Colorado State University

White-lined Sphinx
Hyles lineata
Courtesy Whitney Cranshaw
Colorado State University

White-lined Sphinx Caterpillar
Hyles lineata
Courtesy Whitney Cranshaw
Colorado State University

I vividly remember the first time I saw one – a small winged creature whirring from flower to flower in the evening light, its long tongue dipping for nectar within tube-shaped blooms. I was mesmerized, and struggled for a closer look.

If you’re thinking that I must have seen a hummingbird, you would be making a very common mistake. A mistake, in fact, that has given this critter one of its many nicknames. The winged wonder I saw that summer night was a sphinx moth, also called a hummingbird or hawk moth because of their large size and bird-like characteristics.

In all stages of their life, these insects are large. Caterpillars grow to a robust 4 inches in length and adult wingspans can measure more than 5 inches. Sphinx moths are also some of the fastest insects on earth and have been clocked flying at over 30 miles per hour. Their size, speed, and flying ability reflect those of the hummingbird so closely that they are commonly misidentified.

Sphinx moths are a beloved sight in many Utah gardens. However, they also hold a bit of a devious surprise. The larvae, or caterpillar, of one common species of sphinx moth are well known by vegetable gardeners. They are large and bright green with a distinctive horn near their hind end. Like the adults, these larvae go by many names, the most common being the tomato hornworm. Hornworm caterpillars, unlike their adult counterparts, are not beloved by gardeners. They are voracious beasts with the ability to strip the vegetation off a tomato or pepper plant in one day.

Aside from our garden plants, young hornworms of other species feed on a variety of vegetation including willow, poplar and cottonwood trees. Adult moths rely on a host of flowers such as columbine, honeysuckle, larkspur and evening primrose. Here in Utah you might come across one of a handful of different species in the sphinx moth family including the five-spotted hawk moth and the white-lined sphinx. Look for them in the late summer evenings as daylight begins to fade. But be sure to look twice to avoid mistaking them for something they’re not.

And the next time you find a hornworm on your tomatoes, maybe just relocate the little bugger so that you can enjoy it once metamorphosis changes the beast into a beauty.

For more information and pictures of our native sphinx moths, visit our website at Thank you to Rocky Mountain Power Foundation for supporting the research and development of this Wild About Utah topic.

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

Photos: Courtesy Whitney Cranshaw, Colorado State University,
            Images licensed under Creative Commons Attribution 3.0 License
Text:    Andrea Liberatore, Stokes Nature Center,

Additional Reading:

Cranshaw, W.S. 2007. Hornworms and “Hummingbird” Moths. Colorado State University Fact Sheet 5.517. Found online at:

Buchman, Steve. 2010. Pollinator of the Month: Hawk Moths or Sphinx Moths (Sphingidae). US Forest Service. Found online at:

The Mud-Daubing Wasp

Audio:  mp3

Female Sceliphron caementarium
completing nest cell
Courtesy and
Copyright © 2011 Jim Cane

Pupa of
Sceliphron caementarium
Courtesy and
Copyright © 2011 Jim Cane

The recession has slowed housing starts, but builders of clay dwellings remain busy. Millions of clay homes are built this and every summer in Utah. These dwellings can disintegrate in a summer cloudburst, so you’ll find them beneath overhangs like rock cliffs, or under bridges and the eaves of your house.

These free-standing mud homes are built by a few dozen species of solitary bees and wasps. Among them is the mud dauber, Sceliphron caementarium, a big leggy wasp found throughout Utah. The female wasp constructs hollow clay units one at a time, each the dimensions of a pitted date. The mother mud dauber gathers the wet clay in pellets. At the nest site, she draws the pellet into a ribbon of clay which becomes the next arch of the tubular nest. While working the clay, she audibly buzzes her flight muscles. This vibration visibly liquefies the clay for a few seconds. This strengthens its bond, much as workers in concrete do using large vibrating probes.

The mother wasp then collects spiders, often plucking them straight from their webs after a pitched battle. She permanently paralyzes each spider using her venomous sting. The venom is not lethal. Rather, it is paralytic, keeping the spider alive and fresh but helplessly immobile, a gruesome spider buffet for her grub-like larva to eat. Each hollow nest is packed with a half dozen spiders, one of which receives her egg. In a few weeks time, the growing wasp larva finishes eating its buffet and pupates, becoming dormant for the winter.

Nest building and provisioning by these wasps is a complex result of heritable instincts tailored to local circumstances by learning. It is also a rare trait among insects, most of whom simply lay their eggs and leave. Through observation and manipulative experiments, students of animal behavior have investigated mud-building wasps for well over a century. If you have mud daubers around your home, grab a cool drink, pull up a chair, and enjoy watching their home-making labors.

This is Linda Kervin for Bridgerland Audubon Society.


Images: Courtesy & Copyright Jim Cane, Bridgerland Audubon Society
Text: Jim Cane, Bridgerland Audubon Society

Additional Reading:

“The Wasps”, Evans, Howard E. and Eberhard, Mary Jane West, 1970. Ann Arbor, University of Michigan Press. 265 p. illus.

“Bees, wasps, and ants : the indispensable role of Hymenoptera in gardens”, Grissell, Eric. 2010, 335 p.

Wildlife dispersal in late summer (Or, It’s time to leave the nest!)

Audio:  mp3

Adult great-horned owl
perched at dusk,
hunting for its young
Photo Courtesy & Copyright 2009
Mark Larese-Casanova

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

Late summer is the time of change when the rich nature born of spring matures and enters the next stage of its life. Streams and wetlands may dry up in the heat. Wildflowers wither and produce seeds to ensure a plant’s survival into the future. And, young wildlife leave their place of birth to strike out on their own.

Prior to fledging, young red-tailed hawks build flight muscles by hopping and flapping their wings in the nest. Once they are strong enough, the young red-tailed hawks make excursions from the nest, often soaring together, calling to each other while they fly. This time of year, red-tailed hawk fledglings can still be seen perched atop telephone poles, even in the middle of town, calling to their parents and begging for food. As a bird that usually spends the entire year in Utah, the red-tailed hawk must prepare for its solitary, cold winter ahead.

The calls of great horned owls often echo through the late summer nights. The adult owl soars through an open field while the fledgling owlet is perched nearby, calling for food. The parent responds, and faithfully catches a mouse to feeds its young. Aside from their echoing calls, this all happens quietly and almost invisibly. A lucky observer might spy an owlet and its parent at dusk, but the great horned owl’s soft feathers ensure that their flight is silent, even when just overhead.

Some young reptiles disperse in summer, too, just like birds. Tiny garter snakes, no larger in length or width than a pencil, can often be found slithering across meadows or even lawns. Rather than laying eggs in a nest, the female garter snake retains the eggs in her body until they are ready to hatch. While young garter snakes receive no parental care after birth, the mother hedges her bets by producing upwards of twenty young in the second half of each summer. At least two need to survive over the mother’s life to maintain a stable population.

Fledging and dispersal in late summer is a time of great risk, though. It’s very common in Utah to see road kill of young marmots, skunks, raccoons, and mink, among others. Many inexperienced young animals are also taken by predators. In nature, survival to adulthood is relatively uncommon, so the great investment of the parents is essential for a species to survive.

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


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

Danilson, C.D. Post-Fledging Ecology of Great Horned Owls in South Central Saskatchewan. Master’s Thesis.

Great Horned Owls. All About Birds. Cornell Lab of Ornithology.

Red-tailed hawk. Hawkwatch International.

Red-tailed hawk. Utah Conservation Data Center.

Terrestrial gartersnake. Utah Conservation Data Center.

Thamnophis elegans: Western Terrestrial Garter Snake. Animal Diversity Web.