Seed dynamics are an important part of the life history of plants and may have strong implication... more Seed dynamics are an important part of the life history of plants and may have strong implications on abundance and spatial distribution of populations. In this study, we explored how seed dynamics (removal, predation, germination) interact with micro-environmental conditions to affect the spatial structure of populations of Brahea aculeata (Arecaceae) in a tropical dry forest. B. aculeata is distributed throughout arroyo basins and attains its highest densities near to arroyos/rivers. We hypothesized that: (i) seed removal, predation and germination vary across topographic positions resulting in greater palm abundances adjacent to arroyos and (ii) seed removers/predators respond to both a seed density-dependent effect and a microclimate effect. To test this, in six arroyos basins, seeds were sown across three topographic positions (stream, mid and top of basins) with two seed abundances (1 and 10), protected and non-protected from potential predators. Predation, removal and germination were then followed. After 107 days, 100 % of the exposed seeds were removed/predated and none germinated. For seed removal, we found differences among topographic positions and seed densities with higher removal (up to 80 %) and lower predation rates for grouped seeds. Germination was only observed for protected seeds with higher germination rates in single (17 % ± 9) than in grouped seeds (4 % ± 1). The highest germination and establishment rates were adjacent to the streams; areas which had the lowest light intensity (mean ± SE = 883 ± 160 lm/ft2) and temperatures (mean ± SE = 20.1 ± 0.6 °C), and highest humidity (mean ± SE = 50.8 ± 1.8 %), especially during the rainy season. Differential seedling establishment rates across the landscape due to spatial patterns of seed predation/removal as well as micro-environmental variables appear to have implications for shaping the spatial structure of B. aculeata population at Sierra de Álamos, Mexico.
In this study, we sought to better understand the social, economic, and ecological factors influe... more In this study, we sought to better understand the social, economic, and ecological factors influencing the development of sustainable management practices for Mauritia flexuosa (aguaje) in two Maijuna indigenous communities. Focus groups, semi-structured interviews and household surveys were conducted to document current and historical patterns of aguaje harvest and management, the importance of aguaje to household income, and to identify current harvesting strategies and key perceptions regarding management. This was complemented with ecological sampling in 12 aguaje stands to determine population abundance, population structure, and sex ratio. Results indicated that M. flexuosa stands show clear evidence of past over-exploitation, with a current sex ratio of 3.48 males for each female, and low adult female densities (21 females/ha). Despite this, M. flexuosa remains highly abundant and populations maintain an inverted J-curve structure; however, results also showed a significant relationship between low densities of adult females and low densities of seedlings (R 2 = 0.476; p = 0.013), suggesting that the felling of females from the canopy is reducing recruitment rates. The current state of M. flexuosa populations corroborates the harvest history as told by interviewees that intensive destructive harvesting began in the 1990s and has since waned, primarily due to the decline in the stock of females and low prices. Attempts at non-destructive harvesting, via the use of climbing harnesses has had mixed success as nearly half of the M. flexuosa palms harvested in 2010 were cut down rather than climbed. Scarcity of adult females and low prices resulted in low return on effort, and current income from aguaje accounts for just 5% of the communities' cash income. Results indicated that four factors synergistically interact to hinder development of sustainable aguaje management: (1) low resource stock, (2) market barriers, including poor market access and low prices, (3) limited access to climbing technology and training, and (4) limited organizational experience at a community level, which limits the effectiveness of attempts to mitigate the first three barriers. Despite these challenges, the Maijuna and aguaje have many attributes associated with successful management of natural resources. Our study suggests that in cases where forest resources have already been degraded, transitioning to more sustainable management alternatives can be difficult as a number of ecological and socio-economic factors interact to hinder implementation.
The role of ungulates as contributors to establishment and spread of non-native invasive plants i... more The role of ungulates as contributors to establishment and spread of non-native invasive plants in natural areas is not well known. The objectives of this study were to document whether or not sulfur cinquefoil (Potentilla recta L.) is grazed by ungulates and to quantify the effects of ungulate herbivory on the density and demography of sulfur cinquefoil. Despite reports suggesting sulfur cinquefoil is minimally grazed, our results indicate that substantial grazing of sulfur cinquefoil occurs in a northeastern Oregon natural area. The number of sulfur cinquefoil flowers and seed heads differed significantly (P < 0.0001) among all grazing treatments at all sampling periods. Cattle (Bos Taurus) grazed sulfur cinquefoil throughout early summer, resulting in smaller plants with few flowers and subsequent seed heads. Sulfur cinquefoil was grazed by deer (Odocoileus heminous and O. virginianus) and elk (Cervus elaphus) primarily in the fall and winter by specifically removing just the seed heads. As sulfur cinquefoil reproduces only by seed and seeds typically fall within 3 m of a parent plant, grazing by ungulates and subsequent deposition of the seeds by endozoochory may explain the establishment of satellite infestations across susceptible natural areas.
Fruit from the palm Mauritia flexuosa (aguaje) is harvested throughout the Peruvian Amazon for su... more Fruit from the palm Mauritia flexuosa (aguaje) is harvested throughout the Peruvian Amazon for subsistence and commercial purposes. Recent estimates suggest that residents of Iquitos, the largest city in the region, consume approximately 148.8 metric tons of aguaje fruit per month, the vast majority of which is harvested by felling and killing adult female trees. In this study, we sought to better understand and document the importance of M. flexuosa palm swamps (aguajales) in two Maijuna indigenous communities to inform the sustainable management of this habitat and species. Semi-structured interviews, focus groups, and household surveys were carried out to assess the significance of aguajales and their associated plant and animal resources as well as to determine how the relationship that the Maijuna have with aguajales has changed over time. Aguajales and their associated resources are culturally significant and useful to the Maijuna in a wide variety of ways. In addition to M. flexuosa, the Maijuna use over 60 different species of plants from aguajales. When M. flexuosa is in fruit, aguajales are important hunting areas with a total of 20 different animal species hunted. The Maijuna also have traditional beliefs about aguajales, believing that malevolent supernatural beings reside in them. Notably, the relationship that the Maijuna have with aguajales has changed considerably over the years as aguaje fruit went from a subsistence item collected opportunistically from the ground to a market good destructively harvested beginning in the early 1990s. The Maijuna are concerned not only about how this has affected the future commercial harvest of aguaje but also about its effects on game animals given the importance of hunting to Maijuna cultural identity, subsistence, and income generation. In order to meet the multiple socio-cultural and economic needs of the Maijuna, sustainable management efforts must be expanded to not only focus on the commercial harvest of aguaje but also other facets of their relationship with this habitat. Our study suggests that the research and development of multi-use forest management plans must not be restricted to commercial forest products and ecosystem services given that many communities rely on tropical forests for a wide range of non-market cultural, economic, and subsistence goods and services.
1. Perennial plants often endure chronic loss of leaf area due to recurrent physical damage, herb... more 1. Perennial plants often endure chronic loss of leaf area due to recurrent physical damage, herbivory and, for species used as non-timber forest products, due to leaf harvesting. However, little is known about functional and demographic resilience (extent and speed of recovery) of plants subjected to varying levels of chronic defoliation. 2. We used a dioecious, understorey palm (Chamaedorea elegans) to evaluate temporal trajectories and rates of recovery of leaf functional traits and vital rates (survival, growth and reproduction) after being subjected to experimental chronic defoliation regimes. 3. Pristine populations of mature C. elegans, categorized by gender (male and female), were subjected to five defoliation levels (0%, 33%, 50%, 66% or 100% of newly produced leaves) every 6 months over a period of 3 years (1997)(1998)(1999)(2000). To evaluate recovery from defoliation, surviving palms were monitored for 3 years after the cessation of the defoliation treatment (2000)(2001)(2002)(2003). We recorded leaf functional traits (leaf persistence, leaf production rate, leaf size and leaf area) and annual rates of mortality, growth and reproduction. 4. Cumulative effects of chronic defoliation concomitantly reduced leaf traits, survival, growth and reproduction, and this effect was stronger in female than in male palms, independent of plant size. Recovery from defoliation was faster in males than in females, but proceeded gradually overall. Survival increased first, followed by growth, while reproductive traits showed the slowest recovery rate. Recovery was independent of plant size. Notably, 3 years after defoliation treatment, the standing leaf area and probability of reproduction had not recovered to pre-defoliation levels. Additionally, we found that the occurrence of a severe drought in the first year (2000) after defoliation ceased led to decreased survival, growth and reproduction and the ability of plants to recover from defoliation. 5. Synthesis. Chronic defoliation reduces fitness components of C. elegans palms differentially between genders. Recovery is gradual and is slower and less complete in females compared with males. The lower level of resilience to chronic defoliation shown by female plants may have profound consequences for the dynamics and genetic variability of populations of tropical understorey plants undergoing prolonged defoliation. Such effects may be aggravated by severe drought episodes that are expected to increase in frequency according to global climate change predictions.
Large domestic and native ungulates have the potential to disperse large quantities of seeds thro... more Large domestic and native ungulates have the potential to disperse large quantities of seeds throughout the landscape. Many studies have found that ungulates are capable of dispersing seeds but few quantify the relative importance of ungulate dispersal across the landscape. We investigated the potential for cattle, elk, and deer to disperse native and exotic plants in two different western North American ecosystems in northeast Oregon. We collected fecal samples of cattle, elk and deer that had been deposited during the current growing season. In the greenhouse we monitored the density and species richness of seedlings that germinated from the fecal samples. All three species act as seed dispersers for native and exotic plants. Cattle fecal pats had a higher species richness and density of exotic grasses germinating compared to the other ungulates; elk had a higher species richness and density of native and exotic forbs compared to the other ungulates. We then projected the number of seeds that each animal could disperse during a growing season. We predict that cattle disperse more than an order of magnitude more seeds than elk and deer per animal. Cattle, elk and deer interact with the landscape in different ways and this can have important ramifications for plant communities at local and regional scales. r
In this study, we sought to better understand the social, economic, and ecological factors influe... more In this study, we sought to better understand the social, economic, and ecological factors influencing the development of sustainable management practices for Mauritia flexuosa (aguaje) in two Maijuna indigenous communities. Focus groups, semi-structured interviews and household surveys were conducted to document current and historical patterns of aguaje harvest and management, the importance of aguaje to household income, and to identify current harvesting strategies and key perceptions regarding management. This was complemented with ecological sampling in 12 aguaje stands to determine population abundance, population structure, and sex ratio. Results indicated that M. flexuosa stands show clear evidence of past over-exploitation, with a current sex ratio of 3.48 males for each female, and low adult female densities (21 females/ha). Despite this, M. flexuosa remains highly abundant and populations maintain an inverted J-curve structure; however, results also showed a significant relationship between low densities of adult females and low densities of seedlings (R 2 = 0.476; p = 0.013), suggesting that the felling of females from the canopy is reducing recruitment rates. The current state of M. flexuosa populations corroborates the harvest history as told by interviewees that intensive destructive harvesting began in the 1990s and has since waned, primarily due to the decline in the stock of females and low prices. Attempts at non-destructive harvesting, via the use of climbing harnesses has had mixed success as nearly half of the M. flexuosa palms harvested in 2010 were cut down rather than climbed. Scarcity of adult females and low prices resulted in low return on effort, and current income from aguaje accounts for just 5% of the communities' cash income. Results indicated that four factors synergistically interact to hinder development of sustainable aguaje management: (1) low resource stock, (2) market barriers, including poor market access and low prices, (3) limited access to climbing technology and training, and (4) limited organizational experience at a community level, which limits the effectiveness of attempts to mitigate the first three barriers. Despite these challenges, the Maijuna and aguaje have many attributes associated with successful management of natural resources. Our study suggests that in cases where forest resources have already been degraded, transitioning to more sustainable management alternatives can be difficult as a number of ecological and socio-economic factors interact to hinder implementation.
In recent years, the use of postfire mulch treatments to stabilize slopes and reduce soil erosion... more In recent years, the use of postfire mulch treatments to stabilize slopes and reduce soil erosion in shrubland ecosystems has increased; however, the potential effects on plant recovery have not been examined. To evaluate the effects of mulching treatments on postfire plant recovery in southern California coastal sage scrub, we conducted a field experiment with three experimental treatments, consisting of two hydromulch products and an erosion control blanket, plus a control treatment. The area burned in 2007, and treatments were applied to six plot blocks before the 2008 growing season. Treatment effects on plant community recovery were analyzed with a mixed effects ANOVA analysis using a univariate repeated measures approach. Absolute plant cover increased from 13 to 90% by the end of the second growing season, and the mean relative cover of exotic species was 32%. The two hydromulch treatments had no effect on any plant community recovery response variable measured. For the erosion control blanket treatment, the amount of bare ground cover at the end of the second growing season was significantly lower (P = 0.01), and greater shrub height was observed (P \ 0.01). We conclude that postfire mulch treatments did not provide either a major benefit or negative impact to coastal sage scrub recovery on the study area.
Seed dynamics are an important part of the life history of plants and may have strong implication... more Seed dynamics are an important part of the life history of plants and may have strong implications on abundance and spatial distribution of populations. In this study, we explored how seed dynamics (removal, predation, germination) interact with micro-environmental conditions to affect the spatial structure of populations of Brahea aculeata (Arecaceae) in a tropical dry forest. B. aculeata is distributed throughout arroyo basins and attains its highest densities near to arroyos/rivers. We hypothesized that: (i) seed removal, predation and germination vary across topographic positions resulting in greater palm abundances adjacent to arroyos and (ii) seed removers/predators respond to both a seed density-dependent effect and a microclimate effect. To test this, in six arroyos basins, seeds were sown across three topographic positions (stream, mid and top of basins) with two seed abundances (1 and 10), protected and non-protected from potential predators. Predation, removal and germination were then followed. After 107 days, 100 % of the exposed seeds were removed/predated and none germinated. For seed removal, we found differences among topographic positions and seed densities with higher removal (up to 80 %) and lower predation rates for grouped seeds. Germination was only observed for protected seeds with higher germination rates in single (17 % ± 9) than in grouped seeds (4 % ± 1). The highest germination and establishment rates were adjacent to the streams; areas which had the lowest light intensity (mean ± SE = 883 ± 160 lm/ft2) and temperatures (mean ± SE = 20.1 ± 0.6 °C), and highest humidity (mean ± SE = 50.8 ± 1.8 %), especially during the rainy season. Differential seedling establishment rates across the landscape due to spatial patterns of seed predation/removal as well as micro-environmental variables appear to have implications for shaping the spatial structure of B. aculeata population at Sierra de Álamos, Mexico.
In this study, we sought to better understand the social, economic, and ecological factors influe... more In this study, we sought to better understand the social, economic, and ecological factors influencing the development of sustainable management practices for Mauritia flexuosa (aguaje) in two Maijuna indigenous communities. Focus groups, semi-structured interviews and household surveys were conducted to document current and historical patterns of aguaje harvest and management, the importance of aguaje to household income, and to identify current harvesting strategies and key perceptions regarding management. This was complemented with ecological sampling in 12 aguaje stands to determine population abundance, population structure, and sex ratio. Results indicated that M. flexuosa stands show clear evidence of past over-exploitation, with a current sex ratio of 3.48 males for each female, and low adult female densities (21 females/ha). Despite this, M. flexuosa remains highly abundant and populations maintain an inverted J-curve structure; however, results also showed a significant relationship between low densities of adult females and low densities of seedlings (R 2 = 0.476; p = 0.013), suggesting that the felling of females from the canopy is reducing recruitment rates. The current state of M. flexuosa populations corroborates the harvest history as told by interviewees that intensive destructive harvesting began in the 1990s and has since waned, primarily due to the decline in the stock of females and low prices. Attempts at non-destructive harvesting, via the use of climbing harnesses has had mixed success as nearly half of the M. flexuosa palms harvested in 2010 were cut down rather than climbed. Scarcity of adult females and low prices resulted in low return on effort, and current income from aguaje accounts for just 5% of the communities' cash income. Results indicated that four factors synergistically interact to hinder development of sustainable aguaje management: (1) low resource stock, (2) market barriers, including poor market access and low prices, (3) limited access to climbing technology and training, and (4) limited organizational experience at a community level, which limits the effectiveness of attempts to mitigate the first three barriers. Despite these challenges, the Maijuna and aguaje have many attributes associated with successful management of natural resources. Our study suggests that in cases where forest resources have already been degraded, transitioning to more sustainable management alternatives can be difficult as a number of ecological and socio-economic factors interact to hinder implementation.
The role of ungulates as contributors to establishment and spread of non-native invasive plants i... more The role of ungulates as contributors to establishment and spread of non-native invasive plants in natural areas is not well known. The objectives of this study were to document whether or not sulfur cinquefoil (Potentilla recta L.) is grazed by ungulates and to quantify the effects of ungulate herbivory on the density and demography of sulfur cinquefoil. Despite reports suggesting sulfur cinquefoil is minimally grazed, our results indicate that substantial grazing of sulfur cinquefoil occurs in a northeastern Oregon natural area. The number of sulfur cinquefoil flowers and seed heads differed significantly (P < 0.0001) among all grazing treatments at all sampling periods. Cattle (Bos Taurus) grazed sulfur cinquefoil throughout early summer, resulting in smaller plants with few flowers and subsequent seed heads. Sulfur cinquefoil was grazed by deer (Odocoileus heminous and O. virginianus) and elk (Cervus elaphus) primarily in the fall and winter by specifically removing just the seed heads. As sulfur cinquefoil reproduces only by seed and seeds typically fall within 3 m of a parent plant, grazing by ungulates and subsequent deposition of the seeds by endozoochory may explain the establishment of satellite infestations across susceptible natural areas.
Fruit from the palm Mauritia flexuosa (aguaje) is harvested throughout the Peruvian Amazon for su... more Fruit from the palm Mauritia flexuosa (aguaje) is harvested throughout the Peruvian Amazon for subsistence and commercial purposes. Recent estimates suggest that residents of Iquitos, the largest city in the region, consume approximately 148.8 metric tons of aguaje fruit per month, the vast majority of which is harvested by felling and killing adult female trees. In this study, we sought to better understand and document the importance of M. flexuosa palm swamps (aguajales) in two Maijuna indigenous communities to inform the sustainable management of this habitat and species. Semi-structured interviews, focus groups, and household surveys were carried out to assess the significance of aguajales and their associated plant and animal resources as well as to determine how the relationship that the Maijuna have with aguajales has changed over time. Aguajales and their associated resources are culturally significant and useful to the Maijuna in a wide variety of ways. In addition to M. flexuosa, the Maijuna use over 60 different species of plants from aguajales. When M. flexuosa is in fruit, aguajales are important hunting areas with a total of 20 different animal species hunted. The Maijuna also have traditional beliefs about aguajales, believing that malevolent supernatural beings reside in them. Notably, the relationship that the Maijuna have with aguajales has changed considerably over the years as aguaje fruit went from a subsistence item collected opportunistically from the ground to a market good destructively harvested beginning in the early 1990s. The Maijuna are concerned not only about how this has affected the future commercial harvest of aguaje but also about its effects on game animals given the importance of hunting to Maijuna cultural identity, subsistence, and income generation. In order to meet the multiple socio-cultural and economic needs of the Maijuna, sustainable management efforts must be expanded to not only focus on the commercial harvest of aguaje but also other facets of their relationship with this habitat. Our study suggests that the research and development of multi-use forest management plans must not be restricted to commercial forest products and ecosystem services given that many communities rely on tropical forests for a wide range of non-market cultural, economic, and subsistence goods and services.
1. Perennial plants often endure chronic loss of leaf area due to recurrent physical damage, herb... more 1. Perennial plants often endure chronic loss of leaf area due to recurrent physical damage, herbivory and, for species used as non-timber forest products, due to leaf harvesting. However, little is known about functional and demographic resilience (extent and speed of recovery) of plants subjected to varying levels of chronic defoliation. 2. We used a dioecious, understorey palm (Chamaedorea elegans) to evaluate temporal trajectories and rates of recovery of leaf functional traits and vital rates (survival, growth and reproduction) after being subjected to experimental chronic defoliation regimes. 3. Pristine populations of mature C. elegans, categorized by gender (male and female), were subjected to five defoliation levels (0%, 33%, 50%, 66% or 100% of newly produced leaves) every 6 months over a period of 3 years (1997)(1998)(1999)(2000). To evaluate recovery from defoliation, surviving palms were monitored for 3 years after the cessation of the defoliation treatment (2000)(2001)(2002)(2003). We recorded leaf functional traits (leaf persistence, leaf production rate, leaf size and leaf area) and annual rates of mortality, growth and reproduction. 4. Cumulative effects of chronic defoliation concomitantly reduced leaf traits, survival, growth and reproduction, and this effect was stronger in female than in male palms, independent of plant size. Recovery from defoliation was faster in males than in females, but proceeded gradually overall. Survival increased first, followed by growth, while reproductive traits showed the slowest recovery rate. Recovery was independent of plant size. Notably, 3 years after defoliation treatment, the standing leaf area and probability of reproduction had not recovered to pre-defoliation levels. Additionally, we found that the occurrence of a severe drought in the first year (2000) after defoliation ceased led to decreased survival, growth and reproduction and the ability of plants to recover from defoliation. 5. Synthesis. Chronic defoliation reduces fitness components of C. elegans palms differentially between genders. Recovery is gradual and is slower and less complete in females compared with males. The lower level of resilience to chronic defoliation shown by female plants may have profound consequences for the dynamics and genetic variability of populations of tropical understorey plants undergoing prolonged defoliation. Such effects may be aggravated by severe drought episodes that are expected to increase in frequency according to global climate change predictions.
Large domestic and native ungulates have the potential to disperse large quantities of seeds thro... more Large domestic and native ungulates have the potential to disperse large quantities of seeds throughout the landscape. Many studies have found that ungulates are capable of dispersing seeds but few quantify the relative importance of ungulate dispersal across the landscape. We investigated the potential for cattle, elk, and deer to disperse native and exotic plants in two different western North American ecosystems in northeast Oregon. We collected fecal samples of cattle, elk and deer that had been deposited during the current growing season. In the greenhouse we monitored the density and species richness of seedlings that germinated from the fecal samples. All three species act as seed dispersers for native and exotic plants. Cattle fecal pats had a higher species richness and density of exotic grasses germinating compared to the other ungulates; elk had a higher species richness and density of native and exotic forbs compared to the other ungulates. We then projected the number of seeds that each animal could disperse during a growing season. We predict that cattle disperse more than an order of magnitude more seeds than elk and deer per animal. Cattle, elk and deer interact with the landscape in different ways and this can have important ramifications for plant communities at local and regional scales. r
In this study, we sought to better understand the social, economic, and ecological factors influe... more In this study, we sought to better understand the social, economic, and ecological factors influencing the development of sustainable management practices for Mauritia flexuosa (aguaje) in two Maijuna indigenous communities. Focus groups, semi-structured interviews and household surveys were conducted to document current and historical patterns of aguaje harvest and management, the importance of aguaje to household income, and to identify current harvesting strategies and key perceptions regarding management. This was complemented with ecological sampling in 12 aguaje stands to determine population abundance, population structure, and sex ratio. Results indicated that M. flexuosa stands show clear evidence of past over-exploitation, with a current sex ratio of 3.48 males for each female, and low adult female densities (21 females/ha). Despite this, M. flexuosa remains highly abundant and populations maintain an inverted J-curve structure; however, results also showed a significant relationship between low densities of adult females and low densities of seedlings (R 2 = 0.476; p = 0.013), suggesting that the felling of females from the canopy is reducing recruitment rates. The current state of M. flexuosa populations corroborates the harvest history as told by interviewees that intensive destructive harvesting began in the 1990s and has since waned, primarily due to the decline in the stock of females and low prices. Attempts at non-destructive harvesting, via the use of climbing harnesses has had mixed success as nearly half of the M. flexuosa palms harvested in 2010 were cut down rather than climbed. Scarcity of adult females and low prices resulted in low return on effort, and current income from aguaje accounts for just 5% of the communities' cash income. Results indicated that four factors synergistically interact to hinder development of sustainable aguaje management: (1) low resource stock, (2) market barriers, including poor market access and low prices, (3) limited access to climbing technology and training, and (4) limited organizational experience at a community level, which limits the effectiveness of attempts to mitigate the first three barriers. Despite these challenges, the Maijuna and aguaje have many attributes associated with successful management of natural resources. Our study suggests that in cases where forest resources have already been degraded, transitioning to more sustainable management alternatives can be difficult as a number of ecological and socio-economic factors interact to hinder implementation.
In recent years, the use of postfire mulch treatments to stabilize slopes and reduce soil erosion... more In recent years, the use of postfire mulch treatments to stabilize slopes and reduce soil erosion in shrubland ecosystems has increased; however, the potential effects on plant recovery have not been examined. To evaluate the effects of mulching treatments on postfire plant recovery in southern California coastal sage scrub, we conducted a field experiment with three experimental treatments, consisting of two hydromulch products and an erosion control blanket, plus a control treatment. The area burned in 2007, and treatments were applied to six plot blocks before the 2008 growing season. Treatment effects on plant community recovery were analyzed with a mixed effects ANOVA analysis using a univariate repeated measures approach. Absolute plant cover increased from 13 to 90% by the end of the second growing season, and the mean relative cover of exotic species was 32%. The two hydromulch treatments had no effect on any plant community recovery response variable measured. For the erosion control blanket treatment, the amount of bare ground cover at the end of the second growing season was significantly lower (P = 0.01), and greater shrub height was observed (P \ 0.01). We conclude that postfire mulch treatments did not provide either a major benefit or negative impact to coastal sage scrub recovery on the study area.
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