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<br />Thus, implementing controlled ecological burns could potentially reduce cover of invading
<br />woody plants, enhance the populations of native plant species, and help reduce the abundance of
<br />some undesirable non-native plants.
<br />
<br />Experience with controlled burning in native prairies began in the 1970's at Finley National
<br />Wildlife Refuge, and continued in the 1980's on land at Fern Ridge Reservoir owned by the US
<br />Army Corps of Engineers, and at The Nature Conservancy's Willow Creek Natural Area. Ten
<br />controlled burns, typically covering 10 to 50 acres, have been conducted in the wet prairie
<br />habitats at Willow Creek, in 1986, 1987, 1991, 1994, 1996, 1998, 2001, 2005, 2007, and 2009.
<br />Over the past 15 years, additional controlled burns have occurred on BLM lands in 1996, 1998,
<br />2000, 2005, and 2009, and on City of Eugene land in 2002, 2007, and 2008. In general, the
<br />results of the burns have supported the hypotheses listed above. Typically, new green growth
<br />begins to sprout within two weeks after the burn; species such as tufted hairgrass, the dominant
<br />native grass in wet prairies, grow more vigorously through the fall and winter than in unburned
<br />areas. The following year, and often the following two years, see increases in the flowering and
<br />seed production of many native prairie plants.
<br />
<br />With increased flowering and seed production, the fire adapted species may gradually increase in
<br />population size. For example, a study of the State and Federal listed endangered Bradshaws
<br />lomatium (Lomatium bradshawii) found that within two years of a fire the populations showed
<br />an increase in density of vegetative and reproductive plants (Pendergrass et al., 1999). At Willow
<br />Creek, monitoring data consistently show native species that were used as food plants by
<br />Kalapuya people such as camas (Camassia quamash), wild onion (Allium amplectens), and
<br />yampah (Perideridia spp.) increase in abundance in the year following woody vegetation
<br />removal or controlled burns (Jancaitis 2001). This is consistent with research at Fern Ridge
<br />Reservoir where camas (Camassia quamash), and tarweed (Madia glomerata), two species used
<br />by Kalapuya people, increased in abundance after repeated burning (Taylor 1999, Pendergrass
<br />1995).
<br />
<br />From 2001 to 2007, The Nature Conservancy collected data for an experiment designed to
<br />compare the response of wet prairie species to burning and mowing. Burn and mow treatments
<br />were implemented twice through the duration of the study, in 2001 and 2005. For both, burn and
<br />s in a native species or decreases in
<br />non-native species) were recorded. However, 15 species showed a desirable treatment response
<br />from burning, while only 8 species showed a desirable treatment response from mowing. The
<br />higher level of desirable responses from the burn treatments suggests that fire is a critical
<br />management tool in wet prairie, at least in higher quality native remnants (Nuckols et al., in
<br />press).
<br />
<br />While late summer mowing is a useful management treatment for holding back vegetative
<br />succession, we have observed stronger effects of fire on woody vegetation than from mowing.
<br />While most woody plants (except for conifers) readily sprout after mowing or burning, we have
<br />observed that controlled ecological burns are successful in killing a small percentage of trees and
<br />shrubs outright. After repeated controlled burns, tree stumps become sufficiently damaged that a
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