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How does Intel maintain the integrity of the wetlands at Ronler Acres? Do they just take care of themselves once planted? Unfortunately the answer is no. It takes a lot of work to monitor and keep invasive plants and wildlife under control. What defines invasive species? These are wildlife or plants that are non-native or non-indigenous species which negatively impact areas when they out compete and replace native species. Plant examples include Purple Loosestrife, St. John's Wort, Himalayan blackberry, Reed Canarygrass, and Scotch Broom. Animals of concern include nutria, beavers, and bullfrogs. So what do we do to keep things under control?
Although one of the most beautiful plants seen in the wetlands (due to its showy display of magenta-colored flowers), Purple Loosestrife is highly invasive. They grow from 4 to 10 feet high, and mature plants can have anywhere from 30 to 50 stems arising from a single rootstock. Its dense, homogeneous stands restrict native wetland plant species and reduce habitat for waterfowl.
 Purple Loosestrife can produce up to 2.7 million seeds per plant annually and spread across approximately one million acres of wetlands each year. As it establishes and expands, it out competes and replaces native grasses, sedges, and other flowering plants which provide a higher quality source of nutrition for wildlife. Intel uses the leaf beetle—a biological control recommended by the Oregon Department of Agriculture (ODA)—to keep this plant in check.
 St. John's Wort is native to all of Europe, North Africa, and Asia. It is listed as a weed in the United States and other countries where the plant's spread can be attributed to its use as a medicinal herb and garden favorite. Biological controls (beetles) are used to manage growth. The RA3 wetland uses the ODA recommended and indigenous Klammath Beetle. Reed Canarygrass, Himalayan blackberry, and Scotch Broom are also an ongoing concern. Maintenance includes removal through various methods depending on the plant. Reed Canarygrass and blackberries are cut back. Blackberries are also sprayed with Clean Water Services-approved pesticides in the fall. Scotch Broom is normally removed by hand.
 Nutria are a constant wetlands nuisance. Nutria are large rodents indigenous to South America. They resemble beavers but have rat like tails. They were disseminated widely throughout the world for their fur. Nutria were first introduced in Oregon when an unknown number escaped from a fur farm in Tillamook during a flood in 1937. They are now widespread in Oregon. Nutria are herbivores and can damage dams, berms, and dikes through burrowing. Their feeding activity can lead to the spread of non-native plants within our wetlands. Nutria are trapped to reduce their numbers and minimize their damage to the wetlands. This is in accordance with the Oregon Department of Fish and Wildlife (ODFW), who have adopted administrative rules (OAR 635 Division 056), which prohibit the possession or relocation of some non-native species.
Beavers are not invasive, but they are impactful and pose problems within the wetlands. Beaver activity damages trees and can potentially threaten a wetland ecosystem. Streams and road culverts become obstructed, limiting water flow, while flooding other areas. A permitted vendor provides live trapping and relocation service in accordance with the ODFW.
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Occasionally we receive calls or emails from employees asking "what is that and why is it there." One such example is iron bacteria which are found naturally in soils and waters. Due to the northwest's higher iron concentrations our wetlands have naturally occurring seeps containing iron rich bacteria. Iron bacteria are orange, slimy, smelly, unattractive, and typically observed in anoxic (oxygen deficient) areas. The bacteria are non-toxic and pose no threat to human health. 