Invasive Species in a Flat World

A recent digest of US Department of Agriculture (USDA) press releases and federal register posts caught my eye. It contained five items. Individually, they seem rather ordinary, but together they tell a story. What do you notice?

• USDA Begins Survey Effort to Determine Eradication of Asian Longhorned Beetle in New York County.
• USDA Says Residents Made a Difference in Reducing Invasive Plant Pests and Diseases.
• First Shipments of Mangoes from Pakistan Arrive in the United States.
• USDA Seeks Comment on Pest Risk Analyses for the Importation of Fresh Figs, Pitaya and Pomegranates from Mexico into the Continental United States.
• USDA Seeks Comment on Proposal to Allow the Importation of Tomatoes from West African States into the Continental United States.

Here is evidence that the world really is flat—not just in the economic sense that Thomas Friedman discussed in his brilliant book (2005) “The World is Flat,” but also for invasive species.

It used to be that oceans and mountain ranges provided geographical barriers that kept the pests in one region out of other regions. Not any more. Globalization of trade and travel has flattened the mountains and built bridges across the oceans. An insect lays its egg on a tomato stem in West Africa or under the skin of a mango in Pakistan, and the larva might hatch in New York or Oregon. Likewise, a pallet made from wood infested with Asian longhorned beetle larvae supports a shipment of computer components made in China, and ends up in Washington (actually happened recently).

I know that USDA works hard to assess the risks of agricultural trade and requires mitigation measures to reduce the risks, but there is no perfect system. If you don’t believe me, take an entomologist or a plant pathologist to the produce section of your supermarket. I’m confident they’d be able to find bacteria, insects, and other live hitchhikers. Good places to look: blemishes on potatoes, brown spots on lettuce stems, and the calyx of apples. As you’d expect, organic produce is often biologically interesting. (Somebody ought to study that.)

I’m not anti-globalization. I like bananas on my cereal and grapes in the winter. But I do think we need to be smart about trade. Tomatoes imported from Africa does not sound smart to me—can’t we can grow our own closer to home? What about the customs and border inspection people, you might ask? Don’t they screen out the problems? They do catch a lot, but visual inspections at the border are not the answer. Not only are many of the pests that are coming into our country microscopic, but we only have enough inspectors to look at a small percentage of the commodities we import.

We also need research on safe, economical methods for disinfesting commodities and robust early detection and rapid response programs for the harmful pests that inevitably slip through.

Finally, we need more people that know how and when to report an unusual scale insect on an orange peel or a spider in their bananas. In Oregon, we’ve made it easy: 1-866-INVADER or http://www.oregoninvasiveshotline.org. Keep your eyes open—you can encounter exotic creatures right in your kitchen in a flat world!

Dan Hilburn

Pretty Weeds in Paradise: Ribbon Grass on the Metolius

Ribbon grass along the Metolius River in central Oregon. Photo by Maret Pajutee.

Are there weeds in paradise? Are they pretty?  I’m afraid so. I think I saw them there recently. I love central Oregon, and one of my favorite spots is the headwaters of the Metolius River near Camp Sherman. It is an extraordinarily beautiful place.

Clear, cold water fed by snowmelt from the Cascades springs from a hillside, forming an instant river. Large trout tempt fly fishermen as the river winds through pine forests and meadows past Camp Sherman and on to Lake Billy Chinook. The snow-covered slopes of Mt.Jefferson provide a stunning backdrop.

Recently, after hiking up BlackButte, our group stopped at the Camp Sherman store and bought food for a picnic. We sat down along the river to eat. It was shirtsleeve weather, the scenery was postcard beautiful, and the only bugs were mayflies that the fish were having for dinner. Paradise couldn’t be any nicer; even the grass was pretty -- it was an attractive green and white.

Ribbon grass in front of store on Metolius River. Photo by Maret Pajutee.

As I was soaking up the scenery and eating my salmon burger, it dawned on me that there was something peculiar about the grass. It looked out of place. The rest of the riverside vegetation seemed to belong to the pristine riparian habitat, but the variegated grass stood out like a new Corvette at an antique car show. Once I started looking around, it was everywhere. We hiked downstream for a mile and saw that 6-ft diameter clumps where scattered up and down both banks and on all the islands. A few patches were as big as the cabins nearby.

I pulled up a sample to take to the office for identification, but it wasn’t necessary. Crossing back over the Camp Sherman Bridge, we spotted a small sign pointing out a ribbon grass solarization project. The US Forest Service (USFS) and local teens pulled up the ribbon grass on an island just below the bridge, covered it with landscape fabric, and replanted native sedges. There is a short video describing the project at: http://www.ktvz.com/news/27303106/detail.html

US Forest Service work team handpulling ribbon grass. Photo by Maret Pajutee.

While I applaud the Forest Service for their project, the potential of the demonstrated method doesn’t match the scale of the problem. Walk down the river and you’ll see what I mean. There is a lot of ribbon grass, and it’s displacing the native vegetation and growing out into the river. According to the sign, it first showed up in 2003, so it’s spreading fast. It looks like a classic riparian noxious weed invasion, but it isn’t. Here is why.

Ribbon grass is an ornamental variety of reed canary grass, Phalaris arundinacea. You can probably buy it at your local garden store. The OregonAssociation of Nurseries’ Nursery Guide lists three wholesale nurseries that carry it. Regular reed canary grass (same species, different variety) is a valuable hay and forage species in some situations and is not today considered to be a noxious weed in Oregon.

This creates an awkward situation. An ornamental grass is taking over the banks of one of the premier trout streams in Oregon. It is changing the scenery, and it has to be changing the ecology. Local biologists recognize the problem and see it getting worse, but the Forest Service has to comply with National Environmental Policy Act rules that severely limit control options. All the while, the average fishermen and the general public are oblivious to the invasion. If someone did want to clean it up, people would likely oppose the use of herbicides, given the sensitivity of using chemicals in places where people like to recreate. Other options have been tried (pulling and covering) with limited success. Pulling is probably worse for the ecology of the river because it stirs up lots of sediment. Covering isn’t any better as it kills everything under the plastic – neither are practical given the extent of the invasion and both would require working in the river, which is quite dangerous due to strong currents that can sweep people under fallen logs.

The situation is not out of hand - yet. We have a window of opportunity, and we have the tools to repel this invasion. Pete Schay, with Friends of the Metolius, has demonstrated that aquatic formulations of Rodeo and Habitat work well, especially after the first frost. He’s eliminated the ribbon grass on almost all the private land in the area with no adverse effects to the fish or other wildlife. The ribbon grass that remains is on public land managed by the Forest Service. The Forest Service has been trying to get approval to use herbicides on the Deschutes National Forest for a decade. Maret Pajutee, USFS Ecologist, told me that sensitive issues related to the Metolius are holding up the Environmental Impact Statement. Meanwhile the ribbon grass keeps spreading.

Ironically, if it wasn’t a variegated variety, it wouldn’t look so out of place. This weekend I was biking on the Banks-Vernonia State Trail. Reed canary grass was common on the trail margins. It looked great, and the only thing it was competing with was Himalayanblackberry! Reed canary grass and ribbon grass -- Dr. Jekyll and Mr. Hyde; it is an interesting case.

We’re lucky to live in this beautiful state with special places like the Metolius. Ribbon grass is invading that piece of paradise. Is that acceptable? We all have a stake in this – it’s our public land. Should we do something or not?  What do you think?  

Dan Hilburn

Vacationing with Invasive Species in Mind – Part 2, the Bad Stuff

In my last article, I focused on positive stories related to invasive species from a recent camping trip in the Sierra Nevada. This time I want to talk about the invasive species problems we encountered.

Our route took us 800 miles south on I-5 before we turned left toward Sequoia National Park. The Oregon and northern California stretches of the highway were pleasant and scenic, as highways go. Somewhere south of Sacramento the scenery went to hell. Not only was the air a sickly yellow-brown and the pavement in terrible condition, but yellow star thistle and Russian thistle dominated the non-crop landscape. It was ugly. We couldn’t wait to get out of there. At the southwestern edge of Sequoia National Park, a promontory at 6,700 feet (Moro Rock) has an interpretive panel about the deterioration of air quality that has diminished the westward viewing distance from more than 100 miles when the park was established a century ago to just a few miles today. Thankfully, the eastward view from the same spot, toward the Great Divide, is still spectacular.

The State of California eliminated their noxious weed program this year due to budget cuts. That’s a worry; our staff considered them valuable allies, especially in the area of biological control. Somebody needs to pay attention to the weeds in California, especially in the Central Valley where one-fourth of the food America eats is grown. If they don’t, hell is going to spread. There is one silver lining—ODA hired the best of the California Department of  Food and Agriculture’s (CDFA) laid-off staff, Carri Pirosko, to take over Ken French’s territory (now retired) in southwestern Oregon.

While I’m on the subject of weeds, one of the few weeds noticeable in national parks was cheatgrass. There wasn’t a lot of it, but here and there along the roads and trails, it existed, a reminder of the many invasives waiting in the wings to dominate any landscape. We also encountered a lot of prescribed burning in the forests. Numerous signs explained how the sequoias and other conifers are fire-adapted and how fire improves the forest’s health. I wonder how cheat grass is going to fit into that picture?  It is fire-adapted, too, and extremely invasive. Watch out!

Firewood was also on my mind. In my last article, I mentioned seeing commercial firewood sold in boxes with labeling that included origin information and assurances that the contents met California air quality standards. It was $8.50 a box, not too bad considering it was bigger than a typical bundle, clean and easy to handle, and it included kindling and fire-starter (the cardboard). Other stores were selling firewood for $5.00 to $5.50 per dinky bundle (5-6 sticks). No wonder people like to bring their own.

Someday I hope there is a standard for all commercial firewood so that it is either locally produced or heat-treated to kill insects and plant diseases. Another alternative we should consider is the system used in Canadian National Parks. On last year’s camping trip, we visited Alberta and British Columbia. There they charged us $8 extra for a campfire, but then we had unlimited access to a huge pile of firewood in the middle of the campground. They even provided wheelbarrows! No worries there about people bringing bug-infested firewood with them.

Next, I need to mention cars and crowds. Did you know there are traffic jams in Yosemite? The parking lots are jammed, vultures are circling, and shuttle buses, where they exist, are stuck in traffic jams with all the cars. It is great that people are out enjoying our parks, but we need to get smarter about getting people to the parks and getting them around in the parks. More roads for more cars is not the answer. From an invasive species point of view, roads are pathways and cars are vectors. We need better and smarter transportation alternatives.

Lastly, I have a confession to make. Counter to our Buy It Where You Burn It campaign, I took my own firewood. I didn’t even think about it when I packed our car, and the California border inspector didn’t ask or didn’t notice it. Probably he would have let us keep it anyway, as it was all scrap lumber from carpentry projects—very low risk. Scrap lumber is another issue we’re going to have to deal with as we craft Oregon’s imported firewood regulations. Invasive species exclusion is always harder than you’d imagine. We’ve got our work cut out for us, but I’d rather face our challenges than those of our neighbors to the south.

Dan Hilburn