Monday, December 22, 2014

Invasive noxious weeds impact Oregon economy

December 10, 2014… A newly released economic impact study shows that 25 of Oregon’s most significant invasive noxious weeds cause an estimated annual loss of about $83.5 million to the state’s economy, a figure that could be well over a billion dollars without current control efforts by state, county, and federal weed programs.

“This study is key to showing that noxious weeds not only have a critical environmental impact to native plants, water quality, and threatened and endangered fish and wildlife species, but these invasive weeds have a major impact on Oregon’s economy,” says Tim Butler, manager of the Oregon Department of Agriculture’s Noxious Week Control Program.

The study, Economic Impact From Selected Noxious Weeds in Oregon, was prepared by The Research Group, LLC of Corvallis for ODA, and updates a similar study conducted in 2000. In its executive summary, the final report says “this current study provides an opportunity for ODA to look at the impacts of two widespread invasive weeds, and address the value of potential impact of up and coming noxious weeds. The study reveals the benefits of having safeguards such as prevention, early detection rapid response (EDDR), biological, and other control programs in place to minimize impacts.”

The two widespread noxious weeds examined in the study are Scotch broom and Armenian blackberry, invasive plants that contribute $79.6 million to the current overall economic impact. Those two species– already well established throughout the state– are responsible for 95 percent of the total number of $83.5 million identified in the latest study. The remaining 23 species are limited in distribution and are under intensive management so that they don’t become the next Scotch broom and Armenian blackberry.

“We did predictive modeling in this study showing that if these noxious weeds were left to go everywhere they might go– if we did nothing to control them at their current levels– we could have a potential loss to the state of about $1.8 billion,” says Butler.

The economists who conducted the study use a variety of factors to derive a dollar amount, which is equated to personal income. Factors include livestock losses due to noxious weeds, reduced cattle foraging, reduced wildlife grazing, crop yields, decreased quality of seed and crop, potential impact on marketing and export of agricultural commodities, and even the loss of available fishing and hunting opportunities because of invasive weeds. The $83.5 million is the equivalent to the loss of 1,900 jobs and the $1.8 billion in potential losses if these weeds are unchecked is the equivalent to 40,800 jobs lost.

Butler is quick to point out that the estimated negative impact is conservative.

“The study looks at 25 species, but we are currently working with about 118 noxious weeds in our program that are state listed noxious weeds,” he says. “This is just a subset of that total. So, in reality, if you look at the full list, the total economic impact to the state is much, much larger.”

Nonetheless, the study demonstrates the value of ODA’s Noxious Weed Control Program and similar programs at the county and federal level that keep invasive weeds in check while they are relatively small populations. The “early detection, rapid response” model used by weed control cooperators has kept Oregon from being completely overrun by these undesirable plants and reaching that $1.8 billion scenario.

“On many of these species, we’ve had success in preventing them from getting well established in Oregon and, in some cases, pushing them back,” says Butler. “That’s the good news in that we’ve kept the economic impact number at about the same level since 2000.”

In fact, the earlier study, which analyzed only 21 noxious weeds, reported an estimated loss of $83 million– just half a million less than the latest study. Analysts note the availability, thanks to technology, of better, more precise information that validates the acreages of noxious weeds currently in Oregon. Those advancements also allow for the predictive modeling that shows the potential impact these weeds carry.

Even the two major weeds causing the majority of economic damage could be worse. The use of biological control agents– good bugs fighting bad weeds–  have kept Scotch broom seed somewhat in check even if they don’t actually kill individual plants. Other species, such as purple loosestrife, are being kept at a lower population level than it could be because of effective biocontrol.

The current report echoes a finding from the 2000 study– prevention programs have a benefit to cost ratio of 34 to one. That means for every dollar spent in these efforts, there is a $34 return on investment based on stemming potential losses caused by noxious weeds.

“This study validates the importance of what we do, but it doesn’t mean we don’t need to be doing more,” says Butler. “Our resources are stretched thin at the state and county level as far as dealing with these species, but we have been very efficient and strategic about what we’ve done.”

Governor Kitzhaber’s 2015-17 recommended budget just released this week recognizes the threat of invasive species to Oregon’s environment and economy. He is proposing an additional $500,000 to fund various efforts to combat invasive weeds.

If another weed impact study is done a decade from now, Butler is hopeful it will contain good news.

“I’d like to see that we continue to be successful in at least holding our own and, in some cases, reducing the acreage of many of these invasive weeds in Oregon,” he says. “It all depends on having adequate resources in programs to continue doing the things we are doing. It’s critical to implement effective control programs to contain, and in some cases, move towards eradication of some of these weed species.”

Having solid numbers from the economic impact study will help make the case.

Full report of weed impact study.

For more information, contact Tim Butler at (503) 986-4621.


For an audio recap of this story, please go to http://wp.me/p52oQB-46 and scroll down.

Thursday, December 18, 2014

Consider the invader: Minor differences may have major impact

Despite many similarities between Dreissena species, quagga mussels infested native unionids less severely than zebra mussels. The study suggests that minor differences between closely related invasive species can have major differences in environmental impacts on the native communities.

Tuesday, December 16, 2014

Toxic nectar affects the behavior of insect pollinators

Natural toxins in nectar and pollen can poison insects and affect their memory, behavior and reproductive success, researchers have found. Toxins in lupin pollen cause bumble bees to produce fewer offspring while chemicals found in rhododendron nectar are toxic to honeybees but not bumble bees, toxic effects that could be contributing to the worrying decline in pollinator species.

Monday, December 15, 2014

Remove Privet to Increase Native Earthworm Populations

Very interesting research is reported in Applied Soil Ecology, 'Removal of an invasive shrub (Chinese privet: Ligustrum sinense Lour)reduces exotic earthworm abundance and promotes recovery of native North American earthworms' by Joshua W. Lobe, Mac A. Callaham Jr., Paul F. Hendrix, and James L. Hanula. Applied Soil Ecology is published by Elsevier B.V.
Abstract: this study investigated the possibility of a facilitative relationship between Chinese privet (Ligustrum sinense) and exotic earthworms, in the southeastern region of the USA. Earthworms and selected soil properties were sampled five years after experimental removal of privet from flood plain forests of the Georgia Piedmont region. The earthworm communities and soil properties were compared between sites with privet, privet removal sites, and reference sites where privet had never established. Results showed that introduced European earthworms (Aporrectodea caliginosa, Lumbricus rubellus, and Octolasion tyrtaeum) were more prevalent under privet cover, and privet removal reduced their relative abundance (from >90% to ∼70%) in the community. Conversely, the relative abundance of native species (Diplocardia michaelsenii) increased fourfold with privet removal and was highest in reference sites. Soils under privet were characterized by significantly higher pH relative to reference plots and privet removal facilitated a significant reduction in pH. These results suggest that privet-mediated effects on soil pH may confer a competitive advantage to European lumbricid earthworms. Furthermore, removal of the invasive shrub appears to reverse the changes in soil pH, and may allow for recovery of native earthworm fauna.

Lumbricus terrestris photo by Joseph Berger, Bugwood.org

Saturday, December 13, 2014

Has your neighborhood been invaded?

Do you live in a housing subdivision that used to be farmland? Do you live next door to a self-proclaimed expert gardener with an eye for the exotic? Perhaps you just ordered some bamboo online to plant in your yard as a privacy screen.
Whether or not these scenarios are true for you, chances are invasive plants are attacking your neighborhood. And without your help, we will lose the war on these invaders.

See full article here: http://www.providencejournal.com/opinion/commentary/2014121 . . .

Friday, December 12, 2014

Twelve Invasive Species of Christmas

Twelve Invasive Species of Christmas

A message from Canada. These invasive species can be found in many places in North America. These are twelve presents no one wants to get this holiday season! Make sure you don't give them either by learning how to prevent the spread of invasive species.