Beargrass Research Articles

Three-Year Effects of Crown Removal by Clipping or Burning on Beargrass (Xerophyllum tenax) Size and Biomass

Beargrass (Xerophyllum tenax), an evergreen perennial herb of the northern Rocky Mountains, Pacific Northwest, and northern California, is used in Native American basketry and commercial floral greens. We studied beargrass size and biomass responses to crown removal by clipping or burning over three years in a coast Douglas-fir (Pseudotsuga menziesii var. menziesii) woodland with variable shrub cover in the southeastern Olympic Peninsula of Washington State. Clipping forested plants resulted in 28% mortality, mostly from smaller plants growing under 26% more total cover than the surviving plants; however, only 3% of completely crown-scorched open-grown plants died. Three years after treatment, crown width of surviving plants was only 61% of the pre-treatment size for clipped plants, compared to 88% for completely crown-scorched plants. Regression analyses indicated that the percentage of crown scorch accounted for only 16% and 27% of crown width and foliar height variation, respectively, one year post-burn, decreasing to 10% and 19% at three years post-burn. During the three years after burning, percentage flowering increased linearly to 64% of plants. Three years post-burn, foliar browse was higher on crown-scorched than on non-crown-scorched plants. Although shade tolerant, long-term survival of lowland beargrass is likely limited by combined competition from shrubs and trees. Stand density management is needed to maintain healthy, reproducing populations in the lowlands of western Washington.

Indigenous caretaking of beargrass and the social and ecological consequences of adaptations to maintain beargrass weaving practices

Indigenous ecologies have persisted through major social and ecological changes including settler colonialism. Adaptations have been a necessary part of this resilience, however little attention has been given to the consequences of these adaptations for Indigenous Peoples and ecologies. Without exploring these consequences, we are left with an incomplete understanding of adaptation that potentially obscures social and ecological costs associated with resilience. Here we describe the contemporary caretaking of a culturally-significant plant used in weaving traditions called beargrass (<em>Xerophyllum tenax</em> Melanthiaceae), and discuss how adaptive practices to maintain biocultural connections to beargrass have influenced both socio-cultural and ecological systems. We ask: (1) How is beargrass stewarded and used today? (2) What are the adaptive practices that Indigenous communities in the Pacific Northwest have used to maintain cultural traditions through changing conditions? (3) What are some of the social and ecological consequences of these adaptations? Through semi-structured interviews with cultural practitioners we identified multiple reciprocal practices that form a basis of the caretaking relationship. In order to compensate for a lack of access to beargrass and lack of ability to exercise sovereignty in land management, practitioners described substituting other weaving materials for beargrass, as well as caretaking substitutions. These adaptations were not uniformly accepted and for some either represented significant cultural losses or placed additional burdens on communities. We also collected ecological field data on beargrass. Using structural equation modeling, we found that a key adaptive practice, the substitution of tree pruning for cultural fire, can replicate key short-term benefits of fire for beargrass populations, but does not appear to replicate longer term benefits. In sum, adaptive practices have allowed beargrass traditions to persist through colonialism, but cannot fully substitute for social and ecological benefits of pre-colonial caretaking, and also result in losses and/or additional burdens for communities. Investigating what adaptations to maintain resilience do in communities, and for whom, is necessary in order to fully appreciate the costs and benefits of adaptations that support resilience through various forms of perturbation.

Belowground morphology and population dynamics of two forest understory herbs of contrasting growth forms

Forest understory herbs exhibit a large range of variation in morphology and life history. Here, we expand the reported range of variation by describing the belowground structures of two very different species, Xerophyllum tenax (Pursh) Nutt. and Chimaphila umbellata (L.) Nutt. We excavated individuals in forests of the Cascade Mountains in the Pacific Northwest of the United States. Xerophyllum tenax has short rhizomes but an extensive root system that is exceptionally large among forest understory species. The roots reach 4 m in length and may occupy an area 50 times that of the aboveground canopy. In contrast, C. umbellata has very small roots but an extensive rhizome system. The largest plant we excavated had 57 m of connected rhizomes and still had a seedling source. Both species have long-lived individuals but differ in response to disturbance. On the basis of monitoring 151 permanent 1 m2 plots in an old-growth forest, X. tenax increased only minimally in density over 40 years following tephra deposition from the 1980 eruption of Mount St. Helens, whereas the density of C. umbellata increased substantially. The very different morphology of these two species highlights the large range of variation found among forest herbs, which needs to be considered when examining the forest understory.

Feruloyl sucrose derivatives from the root of Xerophyllum tenax

A phytochemical investigation of the roots of Xerophyllum tenax led to the isolation of three undescribed feruloyl sucrose derivatives along with two known feruloyl sucrose derivatives, heloniosides A and B. This is the first report of their occurrence in the genus Xerophyllum and the family Melanthiaceae. The structures of these compounds were elucidated on the basis of chemical and spectroscopic analysis including 1D and 2D NMR and analysis of MS-MS fragmentation.

Simulated Indigenous fire stewardship increases the population growth rate of an understorey herb

Abstract Understanding how plant populations respond to multiple drivers is increasingly critical for biodiversity conservation under global change. Indigenous knowledge can provide guidance for sustainable management, but the outcome of its application in novel ecosystems is rarely known. Simulating the re‐introduction of Indigenous stewardship in contemporary contexts with population models allows for the comparison of different management scenarios and the elucidation of the mechanisms driving population outcomes. Beargrass Xerophyllum tenax is an ecologically and culturally important understorey plant managed through fire and leaf harvest by Native Americans. We collected demographic and abiotic data on beargrass over 3 years across fire severities in nine populations and conducted an experiment to simulate Native American leaf gathering. These data were used to build integral projections models (IPMs) with soil moisture and light availability as covariates. With these IPMs, we simulated stochastic population growth rates across future fire and leaf harvest scenarios. We then decomposed our simulation results using stochastic life table response experiments (SLTREs). The ‘no fire’ and ‘business as usual’ (180‐year fire return interval, 58% probability of high‐severity fire) scenarios resulted in lower population growth rates than ‘Indigenous fire stewardship’ (10‐year fire return interval, 10% chance of high‐severity fire). SLTREs revealed that Indigenous stewardship led to higher beargrass population growth rates due to greater fire frequency, higher adult survival and increased vegetative reproduction. Fire also interacted with harvest in the simulations; leaf harvest increased population growth rate only in combination with Indigenous fire stewardship. Synthesis. Stochastic and retrospective population dynamics tools combined with an understanding of Indigenous management practices allow for the comparison of future socio‐ecological scenarios as well as mechanistic understanding of differences between scenarios. Simulated Indigenous stewardship supported the long‐term persistence of X. tenax populations while business as usual and no fire did not. The benefits of Indigenous stewardship to population dynamics, and the complexity of interactive effects of multiple drivers, provide further impetus for collaboration across Indigenous and western knowledge systems. Xerophyllum tenax is presented as a model system to explore the influence of Indigenous stewardship, or its absence, on population dynamics.

Fire, leaf harvest, and abiotic factors drive demography of an ecologically and culturally important understory plant

AbstractUnderstanding how multiple simultaneous drivers interact to influence plant demography is critical for protecting plant diversity in the context of global change. Fire is a key disturbance in forested ecosystems, but the interactive effects of fire and other abiotic and management factors on understory plants are poorly understood. Beargrass (Xerophyllum tenax) is perennial herb that provides food, habitat, and nesting material for a wide range of animals. Beargrass populations are prescribe‐burned by Native American experts, and leaves are subsequently harvested at low‐intensity for use in weaving. Leaves for weaving are reportedly becoming harder to find due to lack of fire and competition with commercial harvesters. To elucidate the effects of fire and its interactions with leaf harvest and abiotic factors on beargrass populations, we collected demographic data on more than 1000 individuals over three years across fire severities in combination with individual‐level soil moisture and light measurements. We also conducted an experiment simulating low‐intensity leaf harvest. We built mixed‐effects models to test our predictions that fire would increase growth and reproduction, and that it would mediate the effects of soil moisture and leaf harvest on beargrass growth. Fire increased growth as well as sexual and vegetative reproduction, providing evidence that beargrass is fire‐adapted. Leaf harvest both reduced survival probability and increased the probability of vegetative reproduction. Individual growth increased with early growing season soil moisture in unburned and low‐severity fire areas but did not vary with soil moisture in high‐severity areas. In sum, fire is a key driver of beargrass demography and fire interacted with other factors to influence beargrass vital rates. Understanding the impacts of changes to management and abiotic factors on understory species such as beargrass, and the ecosystem services they provide, requires attention to interactions among multiple environmental factors.

Effects of the Light Environment and Stand History on Beargrass (Xerophyllum tenax) Morphology and Demography

Beargrass (Xerophyllum tenax [Pursh] Nutt.) is an herbaceous, evergreen perennial found in higher elevations of the northern Rocky, Sierra Nevada, Klamath, Siskiyou, Cascade and Olympic Mountains and in coastal areas from Washington to northern California. It is used by Native Americans for basketry and is an important floral green, but the conditions needed for reproduction and commercially valuable characteristics are not well known. We studied how the light environment affects size, morphology, color, and reproduction of a lowland, southeastern Olympic Peninsula beargrass population. We examined beargrass crown size distribution in relation to current and past overstory structure and found that beargrass plants had longer, greener leaves, lower crown density, smaller basal diameter, and fewer vegetative offshoots in shaded areas compared to more open areas. Flowering was less and there were fewer seedlings in shaded areas. Beargrass did not reproduce sexually in areas with < 0.3 of full photosynthetically active radiation (equivalent to at least 50% tree cover in our stand). Beargrass abundance matched the locations of anthropogenically maintained woodland openings that have since become forested preventing beargrass reproduction, suggesting that many plants have survived in the shade for more than 60 years. Overstory removal and prescribed burning in a portion of the stand stimulated sexual and asexual reproduction. We concluded that plants in shaded areas, although of somewhat higher commercial quality, are likely to recover more slowly from foliar harvest, and are less likely to be replaced after mortality. Population sustainability requires periodically or permanently open stand conditions.

A Dynamic Tandem Repeat in Monocotyledons Inferred from a Comparative Analysis of Chloroplast Genomes in Melanthiaceae.

Chloroplast genomes (cpDNA) are highly valuable resources for evolutionary studies of angiosperms, since they are highly conserved, are small in size, and play critical roles in plants. Slipped-strand mispairing (SSM) was assumed to be a mechanism for generating repeat units in cpDNA. However, research on the employment of different small repeated sequences through SSM events, which may induce the accumulation of distinct types of repeats within the same region in cpDNA, has not been documented. Here, we sequenced two chloroplast genomes from the endemic species Heloniopsis tubiflora (Korea) and Xerophyllum tenax (USA) to cover the gap between molecular data and explore “hot spots” for genomic events in Melanthiaceae. Comparative analysis of 23 complete cpDNA sequences revealed that there were different stages of deletion in the rps16 region across the Melanthiaceae. Based on the partial or complete loss of rps16 gene in cpDNA, we have firstly reported potential molecular markers for recognizing two sections (Veratrum and Fuscoveratrum) of Veratrum. Melathiaceae exhibits a significant change in the junction between large single copy and inverted repeat regions, ranging from trnH_GUG to a part of rps3. Our results show an accumulation of tandem repeats in the rpl23-ycf2 regions of cpDNAs. Small conserved sequences exist and flank tandem repeats in further observation of this region across most of the examined taxa of Liliales. Therefore, we propose three scenarios in which different small repeated sequences were used during SSM events to generate newly distinct types of repeats. Occasionally, prior to the SSM process, point mutation event and double strand break repair occurred and induced the formation of initial repeat units which are indispensable in the SSM process. SSM may have likely occurred more frequently for short repeats than for long repeat sequences in tribe Parideae (Melanthiaceae, Liliales). Collectively, these findings add new evidence of dynamic results from SSM in chloroplast genomes which can be useful for further evolutionary studies in angiosperms. Additionally, genomics events in cpDNA are potential resources for mining molecular markers in Liliales.

Forest Site Classification for Cultural Plant Harvest by Tribal Weavers Can Inform Management

Do qualitative classifications of ecological conditions for harvesting culturally important forest plants correspond to quantitative differences among sites? To address this question, we blended scientific methods (SEK) and traditional ecological knowledge (TEK) to identify conditions on sites considered good, marginal, or poor for harvesting the leaves of a plant (beargrass; Xerophyllum tenax) used in tribal basket weaving. We relied on voluntary participation of six expert weavers, a stratified, randomized field sample, discriminant analysis (DA), a standardized color system, and paired t-tests. We accepted each weaver’s classification (good, marginal, or poor) of forested sites for beargrass harvest and then measured forest and plant attributes on two plots at each harvest area in each class (n 72). The DA yielded descriptive but not predictive results. Coarse woody debris (CWD) levels and the number of trees (trees per acre [TPA]) differed significantly between good and poor sites across California, Oregon, and Washington, whereas basal area did not. Good sites had less CWD (P 0.0360) and fewer TPA (P 0.001) than poor sites. Variations in leaf color decreased as the site class for plant harvest improved. Results reveal a crosswalk between ecological knowledge derived via SEK and TEK for culturally important plants.

Fire Effects in a Montane Wetland, Central Cascade Range, Oregon

The stand-replacing Charlton, OR wildfire of 1996 burned several vegetation transects established before the fire, providing an opportunity to document recovery in one upland and five wetland vegetation zones over a 12-year period. Total mean percent cover of vegetation recovered to about 48% of pre-burn levels by year 12. Total cover increased slightly in Carex fen, but decreased in the other five zones. Fire damage was inversely proportional to moisture gradient, and recovery more or less directly proportional to the gradient. Upland Tsuga mertensiana forest sustained the greatest damage and showed the least recovery by year 12, followed by seasonally-flooded Polytrichum commune moss bed, Xerophyllum tenax ecotone, Vaccinium uliginosum shrub swamp, grass-dominated fen, and Carex fen. A transient soil crust of early-seral bryophytes occurred in upland Tsuga mertensiana forest. Cover of shrub, forb, grass, and moss layers declined in vegetation zones at the drier end of the moisture gradient, but increased in grass and sedge-dominated zones at the wetter end of the gradient, at the expense of forb, grass, and sedge layers.

Ecological and Cultural Significance of Burning Beargrass Habitat on the Olympic Peninsula, Washington

To conserve or restore culturally significant plants, one must consider the important role that indigenous land management techniques have played in maintaining habitats of those species. Beargrass (Xerophyllum tenax) is a basketry plant used by Native Americans and is reportedly declining in traditional gathering sites. Many low-elevation beargrass sites on the Olympic Peninsula in Washington were maintained as savannas and wetland prairies through anthropogenic burning prior to European settlement. This study measures short-term (1 and 2 y) effects of reintroducing prescribed burning (both low and high severity) and manual clearing on beargrass growth and reproductive success—flowering, vegetative reproduction, and seedling establishment. High-severity fire led to a significant increase in beargrass seedling establishment and vegetative reproduction over two years but a decline in beargrass cover. Low-severity fire also decreased beargrass cover, but did not significantly affect shoot production or seedling establishment. In areas where vegetation and coarse woody debris were manually cleared, beargrass cover decreased, while shoot production and flowering increased. Neither low-severity fires nor clearing plots affected beargrass seedling establishment. Results indicate that fire is a useful tool for enhancing low-elevation beargrass populations in this region.

Preliminary observations of using smoke-water to increase low-elevation beargrass (Xerophyllum tenax) germination

Abstract Through a greenhouse experiment, we found that smoke-water can be an effective restoration tool in germinating bear-grass (Xerophyllum tenax (Pursh) Nutt. [Liliaceae]) seeds. We studied the effects of smoke-water on germination rates of beargrass seeds collected from low-elevation dry forests of the southeastern Olympic Peninsula of Washington State and from a wetland of the western Peninsula. Seeds received a treatment of either smoke-water or tap water (the control), which was followed by a cold stratification treatment for 0, 8, 10, 12, 14, or 16 wk. The highest success of beargrass seed germination resulted from seeds collected from the wetland habitat being exposed to smoke-water prior to undergoing 14 wk of cold stratification. This study supports the use of smoke technology in restoration when the reintroduction of burning is not feasible.

Beargrass (Xerophyllum tenax) on the Olympic Peninsula, Washington: Autecology and Population Status

We studied the autecology and population status of beargrass (Xerophyllum tenax (Pursh) Nutt.) on the Olympic Peninsula of Washington State, focusing in the Olympic National Forest (ONF). Objectives were to: (1) define and describe beargrass habitat types in the ONF through an exploratory field study, and (2) determine whether beargrass populations in the ONF have declined where the species was historically present. We found three distinct beargrass habitat types in on the ONF: western low elevation, eastern low elevation, and high elevation habitats. These habitat types significantly differ in elevation, slope, topographic moisture, vegetation cover, successional stage, and litter layer thickness. We suggest environmental conditions of these habitat types may be attributed to the glacial and cultural history of the Olympic Peninsula. Beargrass cover in previously established plots on the southeastern Olympic Peninsula declined over the past 17 years, perhaps due to harvesting for the floral industry and ...

Historic Anthropogenically Maintained Bear Grass Savannas of the Southeastern Olympic Peninsula

Abstract This paper documents the existence and character of a little known fire‐maintained anthropogenic ecosystem in the southeastern Olympic Peninsula of Washington State, U.S.A. Due to cessation of anthropogenic burning, there is no longer an intact example of this ecosystem. We present evidence from Skokomish oral tradition, historical documents, floral composition, tree‐ring analysis, stand structure, and site potential to describe former savanna structure and function. We believe this system was a mosaic of prairies, savannas, and woodlands in a forest matrix maintained through repeated burning to provide culturally important plants and animals. The overstory was dominated by Douglas‐fir (Pseudotsuga menziesii). Bear grass (Xerophyllum tenax) likely was a dominant understory component of the savannas, woodlands, and prairie edges. These lands grew forests in the absence of anthropogenic burning. Wide spacing of older trees or stumps in former stands and rapid invasion by younger trees in the late 1800s and early 1900s suggest a sudden change in stand structure. Shade‐intolerant prairie species are still present where openings have been maintained but not in surrounding forests. Bark charcoal, fire scars, tree establishment patterns, and oral traditions point to use of fire to maintain this system. A common successional trajectory for all these lands leads to forested vegetation. These findings suggest that frequent application of prescribed burning would be necessary to restore this ecosystem.

Pollination and seed production in Xerophyllum tenax (Melanthiaceae) in the Cascade Range of central Oregon

Xerophyllum tenax is a mass-flowering, nectarless herb in which self-pollination is unavoidable as anthers shed pollen onto the three, receptive stigmatic ridges attached to each pistil within a few hours after expansion of the perianth. We compared the pollination system with reproductive success in this species through controlled, hand-pollination experiments. Ovaries of flowers sampled from unbagged inflorescences were visited by pollen-eating flies (primarily members of the family Syrphidae), beetles (primarily Cosmosalia and Epicauta spp.), and small bees, and produced normal-sized capsules and mature seeds. Ovaries of flowers from inflorescences bagged to prevent insect pollination produced small capsules containing undeveloped or no seeds. Epifluorescence analyses suggest that 0.95 of the uncovered flowers are cross-pollinated by insects with pollen tubes penetrating style and ovary tissue. Flowers show a "leaky" but early-acting self-incompatibility system. While hundreds of pollen tubes germinate on each stigmatic surface following self-pollination, few pollen tubes penetrate the stigmatic surface and none penetrate the ovary. In contrast, when stigmas are cross-pollinated by hand with pollen from a second inflorescence pollen tubes were seen penetrating style and ovary. Self-incompatibility in X. tenax parallels that of some species of Trillium, a sister genus within the Melanthiaceae.

Relationship Between Xerophyllum tenax and Canopy Density in the Southern Cascades of Washington

Abstract Large-scale commercial harvest of beargrass (Xerophyllum tenax) has been taking place in the Cascades of Washington and Oregon for the past 15 to 20 years. The long, slender leaves are either used fresh or dried and dyed for use in the floral industries in the United States and Europe. Our objectives were to develop a better understanding of beargrass production under different tree canopy (overstory) densities in the Pacific silver fir/big huckleberry/beargrass and the mountain hemlock/big huckleberry/beargrass plant associations in and around the Cispus Adaptive Management Area. We examined differences in beargrass production for different overstory canopy conditions on 10 sites in each association. Results indicated that beargrass quality is not of commercial grade under open canopies (&lt;60% overstory density). For medium and high densities, the interaction between plant association and overstory density was significant for all response variables except harvestable dry mass. Harvestable dry mass of beargrass did not differ between the two associations, but was greater under medium- compared with high-density conditions. For the Pacific silver fir association, the high-overstory-density class had greater basal area of beargrass per site, and plants were larger with longer leaves compared to medium-canopy-density sites. We did not find this relationship for the mountain hemlock association, except for the longest leaf variable. It is unclear why basal area and size of beargrass were more closely related to overstory conditions for the Pacific silver fir association. Evaluation of the sustainability of beargrass as a nontimber forest product will require long-term study of the relationships among environmental variables, beargrass productivity, and beargrass population dynamics. West. J. Appl. For. 19(2):82–87.

20-Hydroxyecdysone 2-β- d-glucopyranoside from the seeds of Xerophyllum tenax

Bioassay/RIA-directed HPLC purification of a MeOH extract of the seeds of Xerophyllum tenax yielded 20-hydroxyecdysone and 20-hydroxyecdysone 2-β- d-glucopyranoside, the latter being a novel natural product. The structures were elucidated primarily on the basis of 1D and 2D NMR spectroscopic evidence. The ecdysteroid agonist activity of these isolates was determined on the B II tumorous blood cell line of Drosophila melanogaster. ED 50 values for 20-hydroxyecdysone and 20-hydroxyecdysone 2-β- d-glucopyra-noside were found to be 8.0 × 10 −9M and 1.3 × 10 −4M, respectively. The significance of the presence of ecdysteroid conjugates in plants is discussed.

The Utilization of Yucca, Sotol, and Bear grass by the Aborigines in the American Southwest. Willis H. Bell and Edward F. Castetter (Ethnobiological Studies in the American Southwest, No. 7, pp. 74. University of New Mexico Bulletin, Biological Series, Vol. 5, No. S. December 1, 1941.)

The Utilization of Yucca, Sotol, and Bear grass by the Aborigines in the American Southwest. Willis H. Bell and Edward F. Castetter (Ethnobiological Studies in the American Southwest, No. 7, pp. 74. University of New Mexico Bulletin, Biological Series, Vol. 5, No. S. December 1, 1941.) - Volume 8 Issue 2