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The following passage explains the challenges facing a population of trees and possible solutions. Today, oaks are plagued with problems. There is lack of regeneration in populations of certain spe- cies. 4.010 such as the acorn weevil and the filbert tne worm eat away at acorns and prevent germination.By undermining the root systems of seedlings andsaplings, ground squirrels, gophers, and other small mammals often prevent these young plants fromreaching tree size. Severe diseases such as suddenoak death, kill many adult oaks. Many mature oaks are having a tough time withesuppression. Inthe past, with light surface fires, the oaks had been able to maintain a stronghold where other plantswere not able to compete and died out. Now oaks are being toppled by trees that have a higher toler-ance for shade and are not fire-resistant; earliersuch trees would have been killed when Native Americans set fires.Given all of these challenges, the "old-growth" oaksthe large old valley oaks, Garry oaks, coast live oaks, and canyon live oaks that have huge girthand large canopiesmay become a thing of the past. These oaks in particular are important becausethere are often more terrestrial vertebrates living in mature oak stands than in seedling and sapling areas. This prevalence of animals occurs becausethe large crowns of such oaks provide cover and feeding sites for a large variety of wildlife.The University of California has embarked on an ambitious and necessary research program calledthe Integrated Hardwood Range ManagementProgram to explore the significant causes of oak decline and offer varied solutions. These includeinvestigating the use of grassing regimes that are compatible with oak seedling establishment reveg-etating sites with native grasses to facilitate bettergermination of oak seedling& documenting insectsand pathogens that attack oaks, and exploring the ways that native people managed oaks in the past. Scientists at the Pacific Northwest Research Stationin Olympia, Washington, and at Redwood NationalPark in northern California are reintroducing theburning practices of Native American& When used in Garry oak ecosystems, fires keep Douglas firs from encroaching on the oaks and promotethe growth of wildflowers that are important foodplants. Further investigations about these firepractices may be essential in figuring out how to maintain oaks in the western landscape today, given that the fires address many of the factors that arenow causing oak declinefrom how to eliminateinsect pests of acorns to how to maintain an openstructure in oak groves.Ecological restoration, the traditional approach to woodland maintenance, refers to humansintervening on a very limited time scale to bringback plants and animals known to have historicallyexisted in an area. The decline of oaks, one of the most significant plants to Native Americans, shows us that humans may play an integral part in therestoration of oak areas. While animals such as jayshave been recognized as crucial partners in oakwell-being, human actions through the eons may also have been key to the oaks' flourishing.Sudden oak death, for example, although ofexotic origin, may be curtailed locally by thinningaround coastal oaks and tan oaks and setting lightsurface fires, simulating ancient fire managementpractices of Native Americans. Indigenous shrubs and trees that grow in association with oaksare hosts to the sudden oak death pathogen. Bylimiting the growth of these shrubs, burning thatmimics earlier Native American ways may reduce opportunities for disease agents to jump fromother plants to oak trees. With a more open envi-ronment, it may be harder for sudden oak death tospread.The oak landscapes that we inherited, which still bear the marks of former Native Americaninteractions, demand a new kind of restoration thatcomplements other forms of ecological restoration.This new kind of restoration could be called eth-nobotanical restoration, defined as re-establishing the historic plant communities of a given areaand restoring indigenous harvesting, vegetationmanagement, and cultivation practices (seedbear-ing, burning, pruning, sowing, tilling, and weeding)necessary to maintain these communities in the long term.Thus, this kind of restoration is not only aboutrestoring plants, but also about restoring the humanplace within nature. Ethnobotanical restoration isviewed not as a process that can be completed, but rather as a continuous interaction between people and plants, as both of their fates are intertwined ina region. Using oaks (through harvesting acornsand making products from all parts of the tree) andhuman intervention (by thinning tree populations and lighting light fires) may offer us ways to benefi-cially co-exist while improving the long-term healthand well-being of the remarkable oak.
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