Weed Watch!

Colorado Weed Management Association

4th Quarter Newsletter 2022

With the end of the field season in sight, or already over for some of us, we can breathe a sigh of relief before diving into winter projects like grant writing, reporting, and planning for next season. Your CWMA Board of Directors and Training Committee have been hard at work preparing for this year's Winter Training. We hope you are as excited as we are and are looking forward to seeing you in person!

Registration for the CWMA 2022 Winter Training is Open!

Don't delay as prices go up on November 3rd!

$269 - Member Early Bird (between now and November 2)

$319 - Member Regular (starting November 3)

$349 - Nonmember Early Bird (between now and November 2)

$399 - Nonmember Regular (starting November 3)

Sponsorship Packages

CWMAs sponsorship packages are a great way to get your business and products in front of industry professionals. Packages range from a government/nonprofit for $250 to our Gold Sponsor level for $1,500. Sponsor packages include exhibit booth space, free registration, recognition on our website and in event marketing, speaking time and more!

Exhibit booth space is also available for $500.

Agenda and Theme

This year's theme for the Winter Training is Water in the West. Our speaker lineup will feature conservation leaders who work to restore riparian areas, along with specialists who will discuss site selection for biocontrols, converting turf, and applications to and near water.

Interested in Serving on the CWMA Board of Directors? Apply Today!

The CWMA Board of Directors is made up of volunteers who help steer the future direction of the organization, bring value to membership, and serve as leaders in the invasive plant management industry. For more information click the button below to view the application!

Applications are due October 19th, 2022.

Nominate a Deserving Colleague for the CWMA Winter Training Awards!

Working in this industry, chances are you know someone who deserves recognition. Don't let their hard work go unnoticed. Nominate them for an award today!

Award categories:

• Newcomer Award
• Lifetime Service Award
• Partnership Award
• Weed Manager of the Year

Nominations are due November 10th, 2022.

Tamarisk Beetle Success Story in Huerfano County

by Charles Bryant, Huerfano County Noxious Weed Manager

The Deceiving Appearance of Southeast Colorado

Within Huerfano County the Cuchara and Huerfano Rivers appear more like ephemeral streams to the average motorist travelling down the I-25 corridor. Leaving the Sangre de Cristo mountain range for what has been described as “moonscape prairie” to the east, it would be easy to assume that the unassuming waterways terminate somewhere out in the perpetually parched landscape. As they make their trek eastward to join the Arkansas River in Pueblo County they fill the seemingly empty eastern canvas with features that unlike the more renowned western slope that chooses to send its stone monuments skyward, this country chooses to entrench its beauty just out of view. The timid river corridors of Huerfano County tell a tale of longevity and persistence as you travel into the eastern void and realize that the area is divided by a network of pinion and juniper lined canyons cut 300-500 feet deep and over a mile wide in many areas.

Nestled among this network of canyons is a remote 6,000-acre BLM property appropriately called Cuchara Canyon. Perhaps the only thing that detracts from the beauty of this area (at least for those familiar with noxious plant species) are the overgrown riverbanks covered with tamarisk. The high canyon walls, boulder strewn landscape and dense vegetation are certainly not ideal for conventional control methods, while aerial treatments pose the risk of destroying the few remaining native cottonwoods and box elders that cling to life among the tamarisk. What better place for biological control?!

The Odd Fellows Colony of Diorhabda carinulata

In 2019 Huerfano County Noxious Weed Department staff descended into the Cuchara Canyon and released the biocontrol Diorhabda carinulata (aka northern tamarisk beetle), provided by the Palisade Insectary. These pioneering miniature weed warriors were given the name of “The Odd Fellows Colony” within the department’s mapping system given their close proximity to an old dilapidated cabin that has a threshold bearing the three linked chain symbol which is associated with the Fraternal Order of Odd Fellows, a once prominent civic organization both locally and nationally. In 2020 department staff was ecstatic to find that not only had The Odd Fellows Colony made it through the winter, but that they had also spread downstream several hundred yards. While defoliation\damage to the host tamarisk was minimal in 2020, it was viewed as an accomplishment given the fact that a number of attempts by other entities within Huerfano County (at other sites) had been unsuccessful in prior years. To bolster this pioneering population department staff performed another release in July 2020.

The March to Pueblo County

 In July 2021 department staff returned once again to the canyon and was overjoyed to find that the Odd Fellows had made themselves quite at home. Considerable yellowing\defoliation was observed within the original release site extending downstream approximately 0.75 miles. It is likely that the Diorhabda had extended both down and upstream beyond this range, but unfortunately high river flows restricted access to outlying areas. Given the high number of larvae and adult beetles observed within the area department staff determined that an additional release was not necessary for the 2021 season. 

As the summer months came about in 2022 department staff were anxious to see if the Odd Fellows had survived for yet another year. Any concern was quickly alleviated as yellowing\defoliation was observed from the rim prior to descending into the canyon for the July 2022 site revisit. Unlike the swollen riverbanks of the prior year, the Cuchara River was found to be nearly dry, save for the random stagnant pools found scattered throughout the river corridor. This allowed nearly unfettered access throughout the entire river bottom. Department staff was astounded to find that the Odd Fellows had spread at an almost exponential rate both up and downstream. The extent of entire tamarisk stand yellowing and defoliation that had previously only been enviously observed by department staff in Palisade Insectary presentations was on full display among the hidden canyon lands of northeast Huerfano County. As anyone who has released a biological control hopes, the Diorhabda blatantly disregarded the jurisdictional boundaries that normally impede control work. To the northeast (downstream), the Odd Fellows had extended nearly four miles from the original release site, crossing an adjoining State Land Board property on their trek past the Huerfano\Pueblo county line into private lands. The northern extent of spread is likely somewhat further than that which was observed, however staff was unable to determine the actual distance due to property access issues. Later site visits in August revealed that the Diorhabda had spread upstream (south) of the original 2019 release site approximately 3.75 miles. 

Please Accept My Apologies ;)

In August 2022 department staff were able to show Nina Louden (Palisade Insectary Tamarisk Program Coordinator) the handy work of the species she has spent so much time and effort establishing in Colorado and abroad. Department staff eagerly led Mrs. Louden down the steep rocky trail to the canyon bottom in nearly 100-degree weather to see ground zero of the original release site. Several specimens and photo\map points were collected, and a great deal of knowledge was shared by Mrs. Louden. Having several other sites to review that day, Mrs. Louden had only a limited amount of time to spend in Huerfano County, so we quickly ascended the steep trail back to the canyon rim.

This is where I feel a public apology may be in order for Mrs. Louden on behalf of my department. While she happily traversed the rugged terrain in sweltering August heat to view the colony, I realized later that I could have made our day much easier, at least when it comes to finding active populations of tamarisk beetles in Huerfano County. As I was sitting at the drive through of our local KFC\Taco Bell the evening after our visit something caught my eye; an eyesore ornamental tamarisk planting nearby was being decimated by Diorhabda larvae and beetles! How or when this “urban” population of Diorhabda set up shop is unknown, but at least next year we could possibly spare the death-march into rattlesnake and cactus country in exchange for tacos and churros during our annual CDA visit. Any of my Upper Arkansas Cooperative Weed Management Area (UACWMA) cohorts know of the critical link between churros and invasive plant species. ;)

Special thanks to: CDA\Palisade Insectary, CWMA, UACWMA and fellow weed managers across the state for their continued support and inspiration.

Weed Awareness Campaign

October Weed of the Month: Yellow Flag Iris (Iris pseudacorus)

prepared by Alicia Doran, Jefferson County Invasive Species Management Coordinator and Pest Inspector

Yellow flag iris is a Watch List species being considered for addition to the state’s weed list by the Colorado Department of Agriculture.

It was imported to North America as an ornamental plant in the late-1700s but has escaped and now infests ditches, streams, and ponds. In some areas it has formed large monocultures and changed the adjacent ecosystems. Thick growths of yellow flag can clog irrigation systems and streams and, by trapping sediment in the roots, can narrow waterways. All parts of the plant are toxic to livestock and other animals.

Plants grow to about 3 feet tall with long sword-like leaves that grow from thick rhizomes in a fan-like arrangement. Leaves are about ½ to 1¼ inch wide, flat with a pronounced midrib. Plants resemble cattails when not in bloom.

The rhizomes can live for over 10 years in the soil and can remain viable for 3 months or more when dry.

Plants generally form flowers after three years. The 2-3-inch-wide flowers are yellow to whitish with three upward facing petals and three downward facing sepals. The sepals usually have dark purplish-brown streaking. Flowering is summer through fall.

Seeds are formed in three-sided pods. Each plant can form several hundred seeds that can survive and float for more than a year, enabling new infestations to establish long distances from existing occurrences.

RESOURCES

New York Invasive Species (Is) Information

https://nyis.info/invasive_species/yellow-flag-iris/#Origin

Washington State Noxious Weed Control Board

https://www.nwcb.wa.gov/weeds/yellow-flag-iris

University of Florida / IFAS / Center for Aquatic & Invasive Plants

https://plants.ifas.ufl.edu/plant-directory/iris-pseudacorus/

Vermont Invasives

https://vtinvasives.org/invasive/yellow-flag-iris

PHOTO CREDITS

Flower - Shaun Winterton, Aquarium and Pond Plants of the World, Edition 3, USDA APHIS PPQ, Bugwood.org

All Others – Jefferson County Invasive Species Management

Learn more about the campaign 

The Weed of the Month is part of the Weed Awareness Campaign and is prepared by Alicia Doran and Tina Travis who are on the Weed Awareness Campaign Subcommittee, which is housed under the Communications and Marketing Committee.

Native Plant Spotlight: Phacelia sericea

By Ethan Proud, Archuleta County Weed and Pest Supervisor

Phacelia sericea goes by many names including purple fringe, silky phacelia, and blue alpine phacelia. It can be found in subalpine and alpine environments the American West. Phacelia sericea can be identified from others in its genus by its cylindrical inflorescence and its yellow to orange anthers.

Some sources place this plant in the Boraginaceae family while others place it in Hydrophyllaceae.