Article of the Month - October, 2006

Early Detention and Rapid Response Results in Better Control of Weeds
by Tim Prather, UI Weed Scientist

I grew up in northern Illinois. I remember some summers of my childhood spent swatting pesky mosquitoes. The problem was so bad one week; we had a mosquito advisory warning, "Don’t go outside, we expect 50 bites per minute." I remember big trucks going down the street in front of my house, spraying insecticides to combat the problem. Finally, a no standing water ordinance was instituted that combined education on where mosquitoes bred with fines for having standing water. The mosquito problem subsided to a more tolerable level and broad-scale spraying ended.

Weeds are a group of pests that we spend time swatting. They can suppress tree growth, increase fire hazard and yes even "bite" you like yellow starthistle that has driven many "hot needles" into my hands and thighs. We continue to receive new species into Idaho with estimates of over 3,500 weedy species potentially coming to North America. In Idaho, we currently have over 90 weedy species that are noxious weeds in surrounding states in addition to the noxious weeds of Idaho. Just this week we received a plant submitted by the UI master gardeners program in Boise that looks like buffalo bur. It is called Porcupine Tomato (Solanum pyrocanthum) and reports from gardeners say it gets big, up to 8 feet tall, it is really spiny and it produces lots of seedlings that are hard to get rid of. We don’t know how it would grow in our forests; should we find out? Or should we work to make sure it does not establish here and cause problems?

We can continue to swat at weed species when we notice they are biting us. We can also come up with effective solutions that allow us to avoid the sting. There is a coordinated effort within the state to work on effective solutions. A committee called the Idaho Weed Coordinating Committee made up of state, federal, tribal, non-governmental, and university representatives have developed a plan for something called Early Detection and Rapid Response.

Early detection and rapid response targets new problems and takes care of them before they become big problems. Experience has shown that the cost of control is low and the chance for complete removal of a weedy species is high if the new infestations are found and eliminated. In California, removal of a small weed patch of less than an acre can involve less than 80 hours of work spread across several years. If the patch isn’t found until it is 100 acres in size it could take 1000 hours of work. Let’s say you pay someone $10 per hour to work on the project; your savings would be $9,200 if the weed patch is removed when it is small.

Early detection requires knowing something about where weeds might show up first. Increase disturbance and the risk of weeds invading goes up, higher elevations generally are at lower risk than lower elevations and finally accessibility is a factor where areas with many roads have increased risk of invasion.

Early detection also requires someone who is familiar with the local plants so that new species that might be weedy are noticed. Noticing something new is vital and finding out what the plant is can be accomplished by sending the plant or pictures of the plant to the Erickson Weed Diagnostic Lab at UI (access it at www.uidaho.edu/weeds). You can also utilize expertise locally with UI county faculty, weed superintendents, master gardeners, and agency botanists.

Rapid response is important to prevent continued expansion. When something new is found the weed superintendent really, really needs to know about it so that a strategy can be designed to make sure the species is removed. Finding the infestations early means an aggressive response can be launched on a small area, usually with great results. Contrary to what I generally hear from people, there have been lots of successful projects where a weedy species was removed from an area. For brevity, two examples include leafy spurge removed from the Lochsa River Drainage by Idaho Department of Transportation, and local managers in a park in Lewiston removed bristly hawksbeard (only known infestation in Idaho).

So other people will take care of this early detection and rapid response for me, right? I don’t think so, my parents had to make sure our tractor tire sand box was full of sand to prevent standing water and pots had to be turned upside down when not used. You can even practice early detection and rapid response on your lands. First become familiar with the plants you have so that new plants are detected. Roads are great entry points for weeds, so watch roads for new plants. Equipment yards, should be monitored to remove plants that come and go with equipment, keep the yards and the equipment clean and you will reduce the chance a new species establishes. If you are going to cut some timber, look around the area and get rid of surrounding weeds before you cut because with greater disturbance comes greater chances for new weed problems. I saw an area that had been clear cut and before it was cut there was some spotted knapweed in the area. I could see every place where logs were skid, and I could see every landing just by looking at the pattern of weed infestation. If you find something you don’t recognize, take it to a weed superintendent, your extension office or send it to our diagnostic lab (directions at www.uidaho.edu/weeds). We will let you know what you have within a week’s time and we can put you in touch with the people that can help if it is a new weed.

Early detection and rapid response should help us avoid future weed problems. Catching weed infestations when they are small saves money in the long run. I don’t need to run educational programs or research projects on another 3,000 weed species and you don’t need the added headache either. If you want to know more about the process, let someone in your extension office know and we can send information on the topic or work to set up a workshop. You have heard of previous ages like the Pleistocene; someone described the movement of invading species as potentially providing us with a new age, the Homogencene where every place looks about the same. We ought to work to keep Idaho, Idaho.