Fine Dining with Invasive Species

Bullfrog legs with blackberry sauce.

            Imagine cooking up a Thanksgiving meal using only invasive species. Some of them are edible, but it would be a culinary challenge with the invaders now established in Oregon. Anyone for stuffed starling with dandelion and garlic mustard greens? Would you like a side of Himalayan blackberry glazed bullfrog legs with that? I think I’ll pass.

Oregonians have a lot to be thankful for this Thanksgiving. Not only do we live in a beautiful state, we share it with relatively few undesirable invasives.We have non-native weeds and pests, but not nearly as many as most other places. We should all be grateful for that.

Oregonians should be thankful our environment is relatively healthy. The trees in our forests are the same ones that have been here for centuries. The Douglas fir, ponderosa pine, and western white oak around us today are the same species (and some of the same trees!) that were here when Native Americans were the only humans in Oregon. This could change; already tanoak and Port Orford cedar are threatened by sudden oak death and Port Orford cedar root rot.

Oregonians that travel for the holidays will visit places where invasive pests and diseases have changed the composition of plants and animals in the environment. Eastern forests provide numerous examples. Chestnut blight, gypsy moth, hemlock wooly adelgid, beech bark disease, and white pine blister rust have forever changed the species composition and degraded the health of eastern forests. Much of the reason for this difference is historical. Intercontinental trade and travel, a key pathway for invasive species, has a longer history on the East Coast. We should be thankful the pilgrims landed in Massachusetts.

We should also be thankful our waterways are in pretty good shape. We don’t have zebra or quagga mussels. We don’t have Asian carp. We don’t have Chinese mitten crabs. Most of our waterways are still dominated by native species. Again that is not the case in many other parts of the world. The Great Lakes are a good example where ecological health and fishing have suffered due to multiple invasions of harmful species.

There are a lot of other problem species that we don’t have thanks to government-run early detection and eradication programs. Some of the harmful species that have been found in Oregon, but eradicated before they became permanently established, include: gypsy moth, Japanese beetle, granualate ambrosia beetle, and kudzu. Battles to eradicate feral swine, African rue, giant hogweed, purple starthistle, distaff thistle, yellowtuft, and Patterson’s curse are ongoing. We should all be thankful for the dedicated people that are fighting back on our behalf.

We should also be grateful that the general public and our elected leaders are waking up to the threat of invasive species. Ten years ago, few people were aware that biological pollution was a growing problem.  Thanks to Oregon Public Broadcasting, the Oregon Invasive Species Council, the Statesman Journal, Oregon Sea Grant, and many other organizations and media outlets, the word is getting out. Not everybody understands how an individual’s actions can make a difference (see last week’s blog), but we’ve definitely turned a corner on public awareness. Our children are getting the message too; Oregon teachers are spreading the word to their students. Oregon State University and Portland State University have been outstanding champions helping to understand and combat sudden oak death, Spartina, purple loosestrife, gypsy moth, and small broomrape.

We should also be thankful for signs that industries in Oregon are paying attention and beginning to step up. The Oregon nursery industry, for instance, taxes itself so that an emergency fund is available to address future invasions. They also helped produce a free publication, GardenSmart Oregon, a Guide to Non-invasive Plants*.  

I hate to say this, but we’re also lucky that so many of our weeds are not bad looking. You have to admit that Scotch broom, gorse, English ivy, and butterfly bush are way better looking than lots of other weeds. Even Himalayan blackberry has an up side when the berries are ripe. However, I’m less thrilled with them now knowing that invasive spotted winged drosophila larvae might be infesting my invasive blackberry fruit!

Let's go back to the idea of feasting on invasive species. If we open the floodgates, we could expand the menu! Wild boar with Chinese mitten crab stuffing anyone? Snakehead with African honey bee-honey glaze? Still not interested? Me neither. Let’s keep ‘em out!

Dan Hilburn

*Available from the Oregon Department of Agriculture, 635 Capitol St. NE, Salem 97301 or <jdavis@oda.state.or.us>

Genetically Modified Bentgrass, Crop, Agricultural Weed, or Noxious Weed?

             Golf course managers would love to have Roundup-resistant bentgrass for their greens. It would make keeping greens weed-free simple and inexpensive. Just spray them with Roundup, and everything but the bentgrass dies. Roundup binds to organic matter and doesn’t persist very long, so it is less harmful to the environment than many other herbicides. Scotts and Monsanto successfully added a gene conferring Roundup resistance to bentgrass a decade ago. The United States Department of Agriculture (USDA) issued permits for trial plantings, including fields in Oregon and Idaho. So far, so good.

            Bentgrass is a perennial plant that is wind pollinated. It will cross-pollinate with some wild grass relatives. Due to concern that trials in the Willamette Valley could result in pollination and marketing problems, the Oregon Department of Agriculture (ODA) worked with Scotts to set up a control area for the genetically modified bentgrass near Madras 90 over the mountains. Some trial fields were also planted near Parma, Idaho. All of these trials were done under USDA permit. From a production point of view, the trials were a success, so Scotts and Monsanto petitioned USDA to deregulate the product so that they could start selling Roundup resistant bentgrass to golf courses. USDA’s review of the deregulation petition has been drawn-out and difficult, and it just got more complicated.

            Two irrigation districts in Malheur County, upwind and across the river from the Parma fields, were recently treating their canal banks with Roundup. All the weeds were dying except one type of grass.  Oregon State University (OSU) tested samples, and it had the Monsanto gene. Somehow the genetically modified (GM) bentgrass moved from Idaho to Oregon, and now exists up and down miles of irrigation canals between Nyssa and Ontario.

            Oregon’s regulations don’t apply, but this is a violation of USDA’s permit. Since it’s discovery, Scotts has been working to eradicate the GM plants along over 20 miles of canal bank.  I hope they succeed.  ODA has helped them identify legal and effective herbicides; there aren’t many – Roundup would normally be the material of choice.

            Longer-term, ODA will be faced with a dilemma. Is this grass just a crop that produces volunteers?  Is it an agricultural weed?  Or is it a potential noxious weed that will cross-pollinate with wild plants and compete with native plants? We don’t know. It is not clear whether we should simply keep our eye on it, or pull out all the stops and go for complete eradication.

            In the meantime, Scotts has set up a hotline (877-375-5139) to report sightings. Give them a call if you come across a low spreading grass that just smiles when you spray it with Roundup. Bentgrass needs plenty of water, so wet/irrigated areas in Central Oregon and downriver from Ontario would be the places to look. It will be interesting to see how this plays out. We could be playing golf on this grass or cussing at it.  Stay tuned.

Dan Hilburn 

Hitchhikers on Vehicles and Christmas Trees

Vehicles are astoundingly effective at picking up and transporting invasive species.  Put another way, invasive species are amazingly good at hitchhiking. Last week I wrote about research on seeds recovered from an Australian car wash. A reader passed on a tip about similar research going on in Montana¹. Those experiments have shown that an SUV or truck driving on non-paved roads would, on average, pick up 176 seeds per 50-mile trip. ATVs were capable of picking up as many as 200,000 seeds over 48 off-road miles (4200 seeds per mile)! Not all of the seeds were from noxious weeds, of course, but hundreds of them were, and that is a problem.

           

            Vehicles aren’t the only vectors for hitchhiking invasive species. This time of year, Oregon Department of Agriculture horticulturists are inspecting and certifying Christmas trees destined for out-of-state markets. Trees on the loading docks now are destined for Mexico, Pacific Rim countries, and Hawaii. The inspectors’ job is to make sure hitchhikers aren’t riding along with the trees. It is a Herculean task. The volume of trees is mind-blowing (7.8 million trees harvested annually in Oregon), and the potential hitchhikers are tiny and well-hidden.

            Yellowjacket queens like to take shelter in Christmas trees during the fall. Hawaiian regulatory officials are concerned that German yellowjacket, Vespula germanica, an invasive species now found throughout most of the United States, including Oregon, will find its way to Hawaii on the Christmas tree express. Our most common native yellowjacket, V. pennsylvanica, invaded the islands years ago and forms enormous colonies there.

            Mexico has a list of potential invaders they are concerned about, including Douglas fir twig weevil and Douglas fir tussock moth (both native to Oregon), and German yellowjacket and European pine shoot moth (invasive species in Oregon). Conscientious growers keep the hitchhikers to a minimum by storing their cut trees off the ground and mechanically shaking trees before baling and loading them.  

So far the first 70 truckloads of Oregon Christmas trees to reach the Mexican border have passed through without incident. However, two containers of Christmas greens were rejected recently in Japan due to another hitchhiker, strawberry root weevil (invasive species). Good job, Japanese inspectors--I’m sorry we missed them on this end.

Government inspectors do catch a lot of potential invaders, but they are only part of the solution. There is a role for us. We can help reduce the spread of invasive species by not transporting hitchhikers. Rinse off your vehicle, boat, ATV, and boots ASAP after leaving natural areas, and this year give your Christmas tree a good shake before bringing it inside. You might be surprised at who was on track to crash your Christmas party!  

Dan Hilburn

¹Rew, L. and F. Pollnac. 2010. Seed Dispersal by Vehicles.  News from the Center for Invasive Plant Management, MT St. Univ.: http://www.weedcenter.org/newsletter/docs/2010-04-seed-dispersal.pdf

Aquaria, Cars, and Muddy Shoes Down Under

Australia and New Zealand have suffered severe impacts from non-native invasive species as diverse as prickly pear cactus, camels, and cane toads. Some of their research on invasive species has been especially eye-opening.  Recently, an article in Biological Invasions caught my attention. It was entitled: The freshwater aquarium trade as a vector for incidental invertebrate fauna (Duggan, I.C. 2010. vol. 12, #11. 3757-3770).

The gist of the article was that all kinds of copepods, ostracods, and other tiny organisms are being shipped around the world by the aquarium trade. The researcher documented 55 incidental hitchhikers from aquaria in 43 New Zealand households. Eight were new records for New Zealand, six others were non-native species already established. Aquarium plankton – it wasn’t even on my list of things to worry about!

A couple of my other favorite examples of how easy it can be to move invasive species also come from Down Under. A researcher collected the sludge washed off cars at a car wash, added it to sterile potting media, and put it in a greenhouse. A total of 18,000 seedlings grew out including 259 different types of plants! The majority were weeds. (Wace, I. 1977. Assessment of dispersal of plant species – car-borne flora in Canberra. Proc. Ecol. Soc. Australia. Vol. 10. 168-186). Dirty vehicles are probably an important vector here, too.

Muddy boots may also play an important role.  An Australian writer tells this story. “I returned from one trip to Africa to find dried mud caked to my sandals. Examining it closely, I found a trove of organic riches: bits of straw, grass seed husks, flakes of snail shell, four seeds and some fungal threads bearing spore heads -- a forensic record of my trip lay scattered before my eyes. One of the seeds was nearly as big as a dried pea, and I thought of sprouting it to see what it was, but a tiny insect later drilled an exit hole in one side.” (Low. T. Feral Future. 1999. Viking. pg. 102).  

I'd love to have results from similar studies closer to home. Anyone know a student in need of a project? We could really use local examples to emphasize the importance of washing your vehicle, cleaning your boots, and not dumping your aquarium water. Little things like these can make a big difference in the fight against invasive species. Thanks for the heads up, mates.

Dan Hilburn