Reflection Essay

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The process of developing my article for Wikipedia started when I did an evaluation and critique on the fire regimes article. I initially chose the article because it was very short and didn’t go into much detail about the characteristics and nature of fire regimes. Given the content we’ve learned in the class, I figured it would be a good article to evaluate. While the content in the original article was accurate, it was lacking. Additionally, the article didn’t always cite material very clearly, which made finding some of the source material difficult. The critique provided a good method for evaluating the criteria for a good Wikipedia article, and I tried to incorporate those things into my article revisions.

I ended up adding significantly to the article and creating new sections that went into more details about the characteristics, scales, mapping, climate change effects, and invasive species effects on fire regimes. I decided on these sections due to feedback from the instructor, the peer review, and my literature sources. I think adding more content in about the regime characteristics is important because there are a variety of factors that contribute to a fire regime, and while they are broad, it helps the reader understand the fundamental definitions of fire regimes and their importance to the natural and physical landscape.

The peer review process was also helpful. It reminded me of what components I should make sure to include within my article as well as thinking critically about other articles. Feedback I received was helpful as it gave me outside perspective on my content and writing structure. She gave me some helpful suggestions on ways to break-up the text and sections a bit more in order to make it more digestible for readers. Feedback I provided to the article on native use of fire was similar in that I provided comments on ways to make the article flow a bit better and break up the text so it is easier for the reader.

To date, I haven’t received any feedback from other Wikipedia contributors. However, the feedback received in class on Friday from other students was helpful. I imagine there may be more feedback from other contributors once I post my article to the main page, however, I did not delete any part of the original article and only plan to add to it. Because I used good sources, I don’t believe there will be a problem with content or standards.

In general, it has been a good experience using Wikipedia as a forum for discussions of class content. Writing an article on Wikipedia is slightly different than a regular research paper, but I think it is good to be able to discuss the content in a way that is easily accessible to others who don’t have a background in the content as a way to increase general knowledge around the world. Once my article is posted, others will be able to access it, and hopefully learn from it as well.  It was good to get a better understanding of the Wikipedia standards as well. Prior to this class, I didn’t realize they had fairly strict standards in place to make sure data and content is correct.

DRAFT article: Fire Regimes

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(**note: my contributions are italicized)

A fire regime is the pattern, frequency, and intensity of the bushfires and wildfires that prevail in an area over long periods of time.[1] It is an integral part of fire ecology, and renewal for certain types of ecosystems. A fire regime describes the spatial and temporal patterns and ecosystem impacts of fire on the landscape, and provides an integrative approach to identifying the impacts of fire at an ecosystem or landscape level.[2] If fires are too frequent, plants may be killed before they have matured, or before they have set sufficient seed to ensure population recovery. If fires are too infrequent, plants may mature, senesce, and die without ever releasing their seed. Fire is a type of disturbance regime that can define an ecosystem.[3][4] Disturbance regimes like fire can change soil erosion, soil formation, nutrient cycles, energy flow, and other ecosystem characteristics. Disruption of an ecosystem can allow changes in species dominance and mutations in individual species.[5] Fire regimes can change with the spatial and temporal variations in topography, climate, and fuel.[6] Understanding the historic fire regime structure is important for understanding and predicting future fire regime changes and the interactions between fire and climates.[2]

Fire Regime Characteristics

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Fire regime classification by ecosystem type. Fire severity and frequency is linked to vegetation type.[7]

Fire regimes are characterized by a variety of factors including vegetation composition, fuel structure, climate and weather patterns, and topography. Because fire regimes are highly dependent on the landscape and ecosystem in which they occur, there is no standard classification for fire regimes. However, characteristics such as those described below are commonly used to characterize fire regimes on a broad scale.[2] Other factors such as post-disturbance successional stages and types of previous management on the landscape may also be used to describe a fire regime's characteristics. Climate directly impacts the frequency, size, and severity of fires, while also affecting fire regime structure by changing the vegetation structure and composition. Fire regimes are also impacted by topography, slope exposure, landscape management, and ignition (which may be human or lightning-caused).[8]

Although characteristics of fire regimes can vary based on regional differences, at a minimum fire regimes are characterized based on an assessment of the impacts on the vegetation and when and how often fires occur in a given landscape. This can be calculated using fire frequency, fire intervals, and fire rotation. Fire frequency a general term that classifies the number of fire events per time period (usually years). Fire intervals is the number of years between fires and is highly dependent on spatial scales. Fire rotation is a measure of calculating the frequency of a fire using past fire events. Fire rotation is best used for large areas that have historic fire patterns and data.[9]

Other fire regime classifications may incorporate fire type (such as ground fires, surface fires, and crown fires), the size of fires, fire severity, fire intensity, seasonality, topography, and degree of variability within fire regimes. Ground fires use glowing combustion to burn organic matter in the soil. Surface fires burn leaf litter, fallen branches, and ground plants. Crown fires burn through to the top layer of tree foliage.[10] Fire extent is the size and spatial similarities of the burning.[6] Fire severity is the impact of fire on the ecosystem, which may include the degree of vegetative mortality, the depth of burn, or other factors which may be site specific. Fire-line intensity is the energy released per unit of measurement per unit of time and is usually a description of flaming combustion.[8] Seasonality is the period of time during the year that the fuels of a specific ecosystem can ignite.[6]

Spatial and Temporal Scales of Fire Regimes

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Fire regimes can be characterized by a wide variety of spatial and temporal scales which may range from highly site-specific to regional scales and from a few years to thousands of years. Understanding the historic range of these scales is crucial to understanding current and future fire regimes. Distinctions should be made between "fire history" and "historic fire regimes". Fire history is a more general term that measures the frequency of fires throughout a landscape. It may not always be possible to describe the type or severity of these past fire events depending on data availability. Historic fire regimes describe the characteristics of fires across a landscape and the relationship and interactions between ecosystem structure and processes.[2]

 
LANDFIRE (Landscape Fire and Resource Management Planning Tools), is a collaborative program between the U.S. Department of Agriculture and Department of the Interior that provides geospatial data on fire regime characteristics such as vegetation, habitat, carbon sources/sinks, fire, etc. The data is used to help map fire events and look at broad scale fire regime effects.[11]

Mapping Fire Regimes

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Recent fire history can be recorded on fire maps and atlases, often using remote sensing to collect and map data over a landscape. Canada developed database12, which was the first nationwide database of its kind. It includes point locations of all fires larger than 200 ha from 1959-1999. The United States has the Monitoring Trends in Burn Severity (MTBS) Project14 which uses satellite data to map fires from 1984 onward. MTBS maps fire severity within the areas burned and provides a standard on fire perimeters and severity for all fires within the U.S. Applications for projects such as these are used in modeling interactions between fire climate and vegetation.[12]

The Landscape Fire and Resource Management Planning Tools (LANDFIRE) classification is another example of a mapping and modeling system used in the U.S. that collects and analyzes vegetative, fire, and fuel characteristics of fire regimes across a variety of landscapes. LANDFIRE is unique in that it uses both historic fire regimes and current fire regimes to analyze differences between past and present characteristics. It describes fire regimes based on their fire frequencies and severities which helps detect changes in fire regimes over time which is helpful in assessing fire climate effects at regional and landscape scales.[13]

Aging Past Fire Events within Fire Regimes

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Understanding historic fire regimes can be difficult, as fire history data is not always reliable or available. Past fire events can be identified using fire scar analysis on trees, age distributions of stands, charcoal samples, or vegetation changes seen over long periods of time. Examining past fire events and historic fire regimes provides a means of examining trends in vegetation and fire-climate interactions over a long time frame. The variability and fire-climate-vegetation interactions of fire regimes are able to be examined in greater detail and over much longer time periods (thousands of years) rather than just decades as provided by examining historical fire records. Studies have found strong correlations between past climate and fire frequency and extent using these historical fire aging methods.[14]

Although fire history data is useful for understanding past fire regimes, changes in fire management, climate, and vegetation do not allow the continuation of the same fire regimes into the future. Models that examine past fire-climate relationships are the best predictors of future fire regime changes.[14]

Effects of Altered Fire Regimes

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Biota that are able to survive and adapt to their particular fire regimes can receive significant benefits: the ability to regrow stronger, greater protection against fire and disease, or new space to grow in formerly occupied locations.[1] As fire regimes change the area, both current and future species may begin to suffer.[1][15] Decreasing fire intervals negatively affect the ability of fire-killed species to recover to pre-disturbance levels, leading to longer recovery times. Some species, such as resprouters, are better able to withstand changing fire regimes through increased resistance and resilience. However, many fire-killed species may be unable to recover if shortened fire intervals persist over time.[15]

Climate Change

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NASA imagery showing the interrelatedness of climate and fire. Active fires are represented by red dots.[16]

Climate change has affected fire regimes globally, with models projecting higher fire frequencies and reduced plant growth as a result of warmer, drier climates. This is predicted to affect fire-intolerant woody species in particular by reducing plant recruitment, growth, and survival, which shortens the fire intervals within these landscapes causing plant extirpation or extinction. A recent model identifying the impacts of climate change and altered fire regimes and plant communities predicts that woody plant extinctions will increase, causing changes in ecosystem structure, composition, and carbon storage. The fire-climate interactions of a changing climate are predicted to reduce population recovery for plants solely dependent on seed production for re-population.[17] In fire adaptive plant communities with stand-replacing crown fires, recruitment occurs in the first year following a fire event. As climates shift to warmer and drier, seedling recruitment is often poor or non-existent. This post-fire recruitment shift means that a decrease in precipitation causes an increase in dry or drought-prone years which causes a decrease in seed recruitment probability. This reduced seed recruitment also increases as fire severity increases in these changing climate shifts.

Warmer climates are projected to increase fire activity and lengthen fire seasons globally. The annual number of extreme fire weather days is projected to increase as increasing temperatures, reduced relative humidity, increased wind speeds, and increased dry fuel loads result in higher fire intensities and severity. These changes will shorten fire intervals, which will reduce the time for plants to accumulate seeds and potentially allowing for selection of more flammable species.[18] The result of these fire interval shifts have been studied globally. A study in southeast Australia found that widespread losses of mountain ash following prolonged wildfire seasons have burned 87% of the species range. Subsequent re-burns of immature mountain ash led to complete regeneration failure and conversion of forest cover to shrubs and grasslands.[19] These patterns have also been seen in the Mediterranean forests of western North America chaparral regions. These climatic shifts in conjunction with altered fire regimes featuring increased fire frequency and shorter fire intervals are causing vegetative communities to shift their rates of growth, reproduction, and recruitment and reduce rates of stand replacement.[17]

Examples of Fire Regimes

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Bushfire is especially important in Australia, where much of the vegetation has evolved in the presence of regular fires caused by the Aboriginal practice of firestick farming. As result, components of the vegetation are adapted to and dependent upon a particular fire regime. Disruption of that fire regime can affect their survival. An example of fire regime dependent species is the Banksia species which is both fire-sensitive and serotinous. In Banksia species, fire also triggers the release of seed, ensuring population recovery. In an ideal fire regime, a plant would need to have sufficient time to mature and build an adequately large bank of seed before the next fire kills it and triggers seed release.

The California chaparral and woodlands ecoregion, covering a large portion of the U.S. state, is dependent on periodic natural wildfires for optimal health and renewal.[3] A study showed that the increasing rural-urban fringe interface and wildfire suppression practices of the last century have resulted in an increased vulnerability to less frequent, more severe wildfires. The study claimed fire suppression increased fuel in coniferous forests. [4] Upon analysis of California Statewide Fire History Database from 1910-1999, it was actually found that fire frequency and the area burned have not declined, furthermore, fire size has not increased.[20] Chaparral fire suppression, unlike fire suppression in coniferous forests, has not affected the natural fire regime, according to a study conducted by the United States Geological Survey. Furthermore, prescribed burning in the shrubland area was also proven ineffective at reducing the risk of wildfires, which are normally driven by high winds and unaffected by modern fire suppression.[4]

Invasive Species Effect on Fire Regimes

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The presence of invasive species can cause changes in the fuel properties of an ecosystem resulting in changes in the fire regime characteristics.[6] This can change the fire regime properties to make it more difficult for native plant species to recover.[21] The loss of native species of plants can effect an entire ecosystem of animals as well.[22]

Cheat Grass

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One example of an invasive species that changed fire regime in Western North America is Bromus tectorum.[21] Historical fire return intervals in the Snake River Plain sagebrush was 60–110 years, but currently, due to the presence of cheat grass, it burns every 5 years.[21] The cheat grass is a continuous source of fuel thus changing the fuel characteristics of the ecosystem. These frequent fires make it difficult to impossible for native vegetation to fully recover.[21]

Brazilian Pepper Tree

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Brazilian pepper trees are encroaching on native plant communities throughout the southeastern U.S. and causing changes to the frequency and severity of fire regimes and ecosystems.[23]

Another example of invasive species affecting fire regimes can be found with the spread of the Brazilian pepper tree (Schinus terebinthifolia) on native plant communities. Native to Brazil, Argentina, and Paraguay, the plant was introduced as an ornamental species and has now established itself in areas well outside of it's native range. Populations exist in Australia, South Africa, the Mediterranean, southern Asia, and the southeastern United States. Brazilian pepper is often found in disturbed soils and substrates and often outcompetes native plant communities creating monoculture-like conditions. South Florida near the Everglades National Park has particularly been affected by its spread, with some studies reporting only 7 species within (6) 100 m2 plots.[24] As Brazilian pepper moves into an area, it creates a sub-canopy layer that often outcompetes grasses and ground cover species. This changes the vegetative cover and densities of the landscape contributing a changed fire regime for the area.[25]

Brazilian peppers are fire adaptive and produce rapidly growing sprouts following fire events, although plant size and stand density are important in determining the post-fire response, with younger plants having higher mortality rates.[25] Fire frequency plays some role in Brazilian pepper establishment, with areas of frequent fires displaying lower abundances of the plant in contrast to areas not regularly burned. A recent model found that a 4-year fire-return interval would eradicate an initial 100 pepper female population within 25 years.[26] In areas where Brazilian pepper occurs, fire regimes have been altered greatly due to fire exclusion and human settlement. Historically, these areas experienced frequent, low-severity fires. Brazilian pepper may reduce fine fuel loads in areas of historically frequent fire, which may increase the fire-return intervals and reduce fire severity in these areas.[25]

Article Evaluation

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I chose to evaluate the Fire regime article, which discusses the concept, effects, and examples of fire regimes and their effect on ecosystems.[27] The article gave a broad overview on the concept of fire regimes, without discussing too in-depth specific details or tangential information unrelated to the topic. The information appeared unbiased, with many of the citations coming from academic studies, public research agencies, or other reliable news source articles.

While the citations all appeared to work, the way the information was cited in the article was somewhat confusing. The article didn't follow a standard citation style, so determining where some of the information in the article came from was difficult at times. Additionally, some of the studies mentioned and cited within the article were 20+ years old, which may not be the most current data available and potentially causing some of the information to be outdated.

The article appears to have been created somewhat recently (April 2017), with no new contributions made since then, and is not part of a larger Wiki Project. There were no conversations occurring on the 'Talk' page, which may mean there have not been multiple contributors to the article. This may not allow for as balanced an article, as multiple contributors may offer a more balanced argument and provide more research and information on fire regimes.

Overall, the information all seemed consistent with what we've learned in class. In particular, I found the information given about fire and its effect on invasive plants interesting, as we frequently used fire as a tool in invasive control in my previous job. The article specifically mentioned cheat grass causing increased fire activity in the western U.S., which has replaced native plant growth in many areas and made it difficult for native plant communities to become established. Including more information on the use of fire in invasive plant control, either in the article or as a link to a separate article, would have been helpful as well.

Addition to Article

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I am choosing to add more information on the fire regime article I critiqued above. I added more information on the "Invasive Species Effect on Fire Regime" section.

"Certain invasive species can also be effectively controlled under certain fire regimes. Simulation models have found that disturbance-based management can control native invasive species when the cause is due to a shifted disturbance in the fire regime. Further research should be done to examine how restoring historic fire regimes can influence non-native invasive species as well."[28]

I think this is an interesting topic, and probably could merit having it's own sub-page within the fire regime article due to the numerous studies and literature available on the topic. I would be interested in using this as my article for the course to add to in a more significant way.

Other Sources to be Used in Article

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"Modeling disturbance-based native invasive species control and its implications for management"[28]

"Grassland fires may favor native over introduced plants by reducing pathogen loads"[29]

"Woody exotic plant invasions and fire: reciprocal impacts and consequences for native ecosystems"[30]

"Wildland Fire in Ecosystems: Fire and Nonnative Invasive Plants"[31]

"Alien Plant Dynamics Following Fire in Mediterranean-Climate California Shrublands"[32]

References

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  1. ^ a b c Pyne, Stephen. "How Plants Use Fire (And Are Used By It)". NOVA online.
  2. ^ a b c d Morgan, Penelope; Hardy; Swetnam; Rollins; Long (1999). "Mapping fire regimes across time and space: Understanding coarse and fine-scale fire patterns" (PDF). International Journal of Wildland Fire. 10: 329–342 – via Google Scholar.
  3. ^ Sousa, WP (1984). "The role of disturbance in natural communities". Annual Review of Ecology and Systematics. 15: 353–391.
  4. ^ Pickett, STA; White, PS (1985). "The Ecology of Natural Disturbance and Patch Dynamics". New York: Academic Press.
  5. ^ Cowling, RM (1987). "Fire and its role in coexistence and speciation in Gondwanan shrublands". South African Journal of Science. 83: 106–112.
  6. ^ a b c d Brooks, Matthew; et al. (2004). "Effects of invasive alien plants on fire regimes". BioScience. 54.7: 677–688. {{cite journal}}: Explicit use of et al. in: |last= (help)
  7. ^ Brown, James K.; Smith, Jane Kapler (2000). "Wildland fire in ecosystems: effects of fire on flora". Gen. Tech. Rep. RMRS-GTR-42-vol. 2 40,56-68. Department of Agriculture, Forest Service, Rocky Mountain Research Station. Retrieved on 2008-07-20
  8. ^ a b Taylor, Alan H.; Skinner, Carl N. (2003-06-01). "Spatial Patterns and Controls on Historical Fire Regimes and Forest Structure in the Klamath Mountains". Ecological Applications. 13 (3): 704–719. doi:10.1890/1051-0761(2003)013[0704:spacoh]2.0.co;2. ISSN 1939-5582.
  9. ^ Baker, William (2009). Fire Ecology in Rocky Mountain Landscapes. Island Press. pp. 131–163. ISBN 978-1597261838.
  10. ^ "Fire Spread". nps.gov. National Park Service. Retrieved 23 October 2016.
  11. ^ "LANDFIRE Program: Home". www.landfire.gov. Retrieved 2017-12-04.
  12. ^ Rollins, Matthew; Keane; Parsons (2004). "MAPPING FUELS AND FIRE REGIMES USING REMOTE SENSING, ECOSYSTEM SIMULATION, AND GRADIENT MODELING" (PDF). Ecological Applications. 14: 75–95 – via Google Scholar.
  13. ^ "LANDFIRE Program: Home". www.landfire.gov. Retrieved 2017-11-09.
  14. ^ a b Whitlock, Cathy; Higuera; McWethy; Briles (2010). "Paleoecological Perspectives on Fire Ecology: Revisiting the Fire-Regime Concept" (PDF). The Open Ecology Journal. 3: 6–23 – via Google Scholar.
  15. ^ a b Enright, Neal J.; Fontaine, Joseph B.; Lamont, Byron B.; Miller, Ben P.; Westcott, Vanessa C. (2014-11-01). "Resistance and resilience to changing climate and fire regime depend on plant functional traits". Journal of Ecology. 102 (6): 1572–1581. doi:10.1111/1365-2745.12306. ISSN 1365-2745.
  16. ^ NASA
  17. ^ a b Enright, Neal J; Fontaine, Joseph B; Bowman, David MJS; Bradstock, Ross A; Williams, Richard J (2015-06-01). "Interval squeeze: altered fire regimes and demographic responses interact to threaten woody species persistence as climate changes". Frontiers in Ecology and the Environment. 13 (5): 265–272. doi:10.1890/140231. ISSN 1540-9309.
  18. ^ D'Antonio, Carla M.; Vitousek, Peter M. (1992-11-01). "Biological Invasions by Exotic Grasses, the Grass/Fire Cycle, and Global Change". Annual Review of Ecology and Systematics. 23 (1): 63–87. doi:10.1146/annurev.es.23.110192.000431. ISSN 0066-4162.
  19. ^ Bowman, David M. J. S.; Murphy, Brett P.; Neyland, Dominic L. J.; Williamson, Grant J.; Prior, Lynda D. (2014-03-01). "Abrupt fire regime change may cause landscape-wide loss of mature obligate seeder forests". Global Change Biology. 20 (3): 1008–1015. doi:10.1111/gcb.12433. ISSN 1365-2486.
  20. ^ Keeley, Jon E., C. J. Fotheringham, and Marco Morais. "Reexamining fire suppression impacts on brushland fire regimes." Science 284.5421 (1999): 1829-1832.
  21. ^ a b c d Whisenant SG. 1990. Changing Fire Frequencies on Idaho's Snake River Plains: Ecological and Management Implications. Logan (UT): US Department of Agriculture, Forest Service, Intermountain Research Center. General Technical Report INT-276. ☁
  22. ^ Knick ST, Dobkin DS, Rotenberry JT, Schroeder MA, Vander Haegen WM, Van Riper C III.. 2003. Teetering on the edge or too late? Conservation and research issues for avifauna of sagebrush habitats. The Condor. 105: 611-634.
  23. ^ "LANDFIRE Program: Home". www.landfire.gov. Retrieved 2017-12-04.
  24. ^ Villalobos-Vega, Randol (2010). "Water table and nutrient dynamics in neotropical savannas and wetland ecosystems". dissertation: 119 – via University of Miami.
  25. ^ a b c "Schinus terebinthifolius". www.fs.fed.us. Retrieved 2017-11-09.
  26. ^ Stevens, Jens; Beckage, Brian (2009). "Fire feedbacks facilitate invasion of pine savannas by Brazilian pepper (Schinus terebinthifolius)". New Phytologist. 184: 365–375 – via PubMed.
  27. ^ "Fire regime". Wikipedia. 2017-04-19.
  28. ^ a b Shackelford, Nancy; Renton, Michael; Perring, Michael P.; Hobbs, Richard J. (2013). "Modeling disturbance-based native invasive species control and its implications for management". Ecological Applications. 23 (6): 1331–1344. doi:10.2307/23596828.
  29. ^ Roy, Bitty A.; Hudson, Kenneth; Visser, Matt; Johnson, Bart R. (2014). "Grassland fires may favor native over introduced plants by reducing pathogen loads". Ecology. 95 (7): 1897–1906. doi:10.2307/43494870.
  30. ^ Mandle, Lisa; Bufford, Jennifer L.; Schmidt, Isabel B.; Daehler, Curtis C. (2011-08-01). "Woody exotic plant invasions and fire: reciprocal impacts and consequences for native ecosystems". Biological Invasions. 13 (8): 1815–1827. doi:10.1007/s10530-011-0001-3. ISSN 1387-3547.
  31. ^ Zouhar, Kristin; Smith, Jane Kapler; Sutherland, Steve; Brooks, Matthew (2008). Wildland Fire in Ecosystems: Fire and Nonnative Invasive Plants. Ogden, Utah: U.S. Department of Agriculture. ISBN RMRS-GTR-42-vol. 6.. {{cite book}}: Check |isbn= value: invalid character (help)
  32. ^ Keeley, Jon E.; Baer-Keeley, Melanie; Fotheringham, C. J. (2005). "Alien Plant Dynamics Following Fire in Mediterranean-Climate California Shrublands". Ecological Applications. 15 (6): 2109–2125. doi:10.2307/4543509.