   Biological Pollution - July 17, 2002 Jeff Schalau, County Director, Agent, Agriculture & Natural Resources Arizona Cooperative Extension, Yavapai County The 1960's and 1970's heightened national awareness about pollution and environmental quality. At least that's how I remember it. The television commercial showing a Native American man canoeing a polluted stream, looking at litter, then shedding a tear over what he saw was a powerful message. In general, I think we've done a good job reducing pollution and improving environmental quality over the last 35 years. Our success is related to the manner in which chemicals behave in the environment. The forces that carry chemical pollutants (gravity, diffusion, osmosis, etc.) are predictable. Within the last 10 to 15 years, we have begun a new fight against pollution: biological pollution. I first heard this name used at an invasive weed conference and it really makes sense. Biological pollutants are invasive, non-native plants, animals, insects, and other living organisms that decrease our quality of life and cost billions of dollars to control (usually eradication is not possible). The movement and spread of biological pollutants is much more difficult to predict. They do not follow the rules of physics. To make matters worse, spread of biological pollutants has been augmented by our ever improving transportation network and the expansion of world trade. In Arizona, we have had first hand experience with biological pollutants. Imported red fire ants have been found in Arizona traveling in contaminated nursery stock. The ant populations were contained, but are still being controlled and monitored. Giant salvinia (a floating water fern) was found in irrigation canals along the Colorado River where there is little hope of eradication. This plant can double its size in a week, forms a solid mat on top of the water surface, which eliminates light and prevents oxygen from diffusing into the water body. More recently, the glassy-winged sharpshooter (an insect related to leafhoppers) has been found in an Arizona nursery. This insect causes damage to a host of ornamental and agricultural plants, most notably; it vectors the bacterium that causes Pierce's Disease in grapes. Having an interest in plant science, my attention is usually focused on invasive plants. In our local area, there are several invasive, noxious (state or federally regulated) weeds. In the Verde Valley, we have Dalmatian toadflax, Russian knapweed, spotted knapweed, yellow starthistle, hoary cress (whitetop), and sweet resinbush. In the Verde River and its tributaries, we have floating water primrose, Eurasian watermilefoil, and probably others. The Arizona Department of Agriculture is currently revising and adding 16 plants to the Arizona noxious weed list. Several of the proposed additions are plants commonly found in the Verde Valley. These include: tree of heaven (Ailanthus altissima), Russian olive (Elaeagnus angustifolia), giant reed (Arundo tenax), saltcedar (Tamarix spp.), Himalayan blackberry (Rubus discolor), and Malta starthistle (Centaurea melitensis). Citizens are invited to make comments on the rule revisions. For more information, contact Dr. Ed Northam, Noxious Weed Program Coordinator, at (602) 542-3309 or E-mail at ed.northam@agric.state.az.us. The USDA Animal and Plant Health Inspection Service (APHIS) and Arizona Department of Agriculture are the primary regulators for plant and animal invaders in Arizona. However, many other groups are becoming interested and joining the campaign. The USDA APHIS web site is at www.aphis.usda.gov. The Arizona Department of Agriculture web site is at agriculture.state.az.us. Biological pollution is a serious threat to our day-to-day lives and I encourage you to learn more about it. The University of Arizona Cooperative Extension has publications and information on noxious weeds and non-native insects. Learning to recognize these unwanted visitors is the first step in controlling their spread. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 or E-mail us at mgardener@verdeonline.com and be sure to include your address and phone number. Find past Backyard Gardener columns or submit column ideas at the Backyard Gardener web site: http://ag.arizona.edu/yavapai/anr/hort/byg/. |