Photo Credit: Jessie Vinje
| Historically present | |
| Currently present | |
| Currently not detected |
Goal: Maintain or enhance existing Dehesa beargrass occurrences and establish new occurrences, as needed, to ensure multiple conserved occurrences with self sustaining populations to increase resilience to environmental and demographic stochasticity, maintain genetic diversity, and ensure persistence over the long term (>100 years) in chaparral vegetation communities.
Management units: 3
Beginning in 2017 and continuing every 5 years, thereafter, continue inspections of Dehesa beargrass occurrences on Conserved Lands (see occurrence table) begun in 2014 using the IMG regional monitoring protocol to record abundance/map perimeters and collect threats and covariate data to determine management needs.
| Action | Statement | Action status | Projects |
|---|---|---|---|
| IMP-1 | Based upon occurrence status and threats, determine management needs including whether routine management or more intensive management is warranted. | in progress | |
| IMP-2 | Submit project metadata, monitoring datasets and management recommendations to the MSP Web Portal. | in progress |
| Criteria | Deadline year |
|---|---|
| Surveys Completed in 2017 with Management Recommendations | 2021 |
| Threat Name | Threat Code |
|---|---|
| Altered fire regime | ALTFIR |
| Climate change | CLICHN |
| Invasive plants | INVPLA |
| Loss of connectivity | LOSCON |
Management units: 3
Beginning in 2017, conduct routine management actions begun in 2014 identified through the IMG regional protocol monitoring on Conserved Lands. Depending on the type and level of threat, management should only be conducted as needed, not necessarily every year, and using BMPs with precautions to do no harm.
| Action | Statement | Action status | Projects |
|---|---|---|---|
| IMP-1 | Perform routine management activities such as protecting occurrences from disturbance through fencing and enforcement and controlling invasive non-native plant species to less than 20% relative cover. | some occurrences are in progress | |
| IMP-2 | Submit project metadata and management data to the MSP Web Portal. | some occurrences are in progress |
| Criteria | Deadline year |
|---|---|
| Routine Management Completed as Needed Based Upon Monitoring Recommendations | 2021 |
| Threat Name | Threat Code |
|---|---|
| Altered fire regime | ALTFIR |
| Climate change | CLICHN |
| Invasive plants | INVPLA |
| Loss of connectivity | LOSCON |
Management units: 3
By 2017, refine BMPs for Dehesa beargrass based on results of experimental management studies currently in progress, as well as research studies. Submit all data and reports to MSP web portal.
| Action | Statement | Action status | Projects |
|---|---|---|---|
| DEV-1 | Refine BMPs by incorporating results of management experiments to control invasive species that threaten Dehesa beargrass populations in San Diego County (e.g., Brachypodium removal project). | In progress | |
| DEV-2 | Submit project metadata, monitoring data, reports and management recommendations to MSP web portal. | In progress |
| Criteria | Deadline year |
|---|---|
| BMPs for Dehesa Beargrass Completed by 2018 | 2021 |
| Threat Name | Threat Code |
|---|---|
| Altered fire regime | ALTFIR |
| Climate change | CLICHN |
| Invasive plants | INVPLA |
| Loss of connectivity | LOSCON |
Management units: 3
In 2019, begin preparing a section for Dehesa nolina in the MSP Rare Plant Management Plan that prioritizes management actions to maintain or expand conserved occurrences based upon an assessment of data on occurrence status habitat and threats. Minimum criteria for enhancement are to reduce invasive annual nonnative plants and thatch to less than 20% absolute cover within the occurrence
| Action | Statement | Action status | Projects |
|---|---|---|---|
| PRP-1 | Consult the San Diego County Rare Plant Working Group made up of plant ecologists, geneticists, rare plant experts, land managers, restoration practitioners, seed banking and bulking practitioners, wildlife agencies, and other stakeholders to provide input and recommendations for Dehesa nolina in the Rare Plant Management Plan. | on hold | |
| PRP-1 | Consult the San Diego County Rare Plant Working Group made up of plant ecologists, geneticists, rare plant experts, land managers, restoration practitioners, seed banking and bulking practitioners, wildlife agencies, and other stakeholders to provide input and recommendations for Dehesa nolina in the Rare Plant Management Plan. | on hold | |
| PRP-2 | Develop a conceptual model that identifies management actions to effectively reduce threats to Dehesa nolina populations. | on hold | |
| PRP-3 | Prioritize occurrences for management based upon an assessment of occurrence status, the potential for management to significantly reduce identified threats, and the availability of adjacent suitable habitat for occurrence expansion. | on hold | |
| PRP-4 | Develop an implementation plan for Dehesa beargrass that prioritizes management actions for the next 5 years and details tasks, lead entities, responsibilities, and timelines, budgets. | on hold | |
| PRP-5 | Submit project metadata and MSP Rare Plant Management Plan to the MSP Web Portal. | on hold |
| Criteria | Deadline year |
|---|---|
| By 2020, Completed Dehesa Nolina Section in the MSP Rare Plant Management Plan | 2021 |
| Threat Name | Threat Code |
|---|---|
| Altered fire regime | ALTFIR |
| Climate change | CLICHN |
| Invasive plants | INVPLA |
| Loss of connectivity | LOSCON |
Management units: 3
Beginning in 2020, implement highest priority management actions identified in the Dehesa nolina section of the MSP Rare Plant Management Plan.
| Action | Statement | Action status | Projects |
|---|---|---|---|
| IMP-1 | Implement site-specific invasive control management actions for a minimum of 3 years to reduce invasive nonnative plants to =20% absolute cover in Dehesa nolina suitable habitat based onthe Dehesa nolina Management Plan, and results from BMP studies (e.g., Brachypodium removal project). Actions may include thatch removal and invasives control using herbicide or mechanical methods. | waiting for precedent action | |
| IMP-2 | Based on the response of Dehesa nolina to initial management actions, determine need for (1) further invasives control and (2) additional habitat enhancement such as seeding of additional native plant species that support pollinator communities or facilitate sustainable Dehesa nolina populations by inhibiting germination and growth of invasive species. | waiting for precedent action | |
| IMP-3 | Submit project metadata, reports and management recommendations to MSP web portal. | waiting for precedent action |
| Criteria | Deadline year |
|---|---|
| By 2024, =1 High Priority Management Action Implemented for Dehesa Nolina from the MSP Rare Plant Management Plan | 2021 |
| Threat Name | Threat Code |
|---|---|
| Altered fire regime | ALTFIR |
| Climate change | CLICHN |
| Invasive plants | INVPLA |
| Loss of connectivity | LOSCON |
Management units: 3
Monitor the effectiveness of highest priority management actions identified in the Rare Plant Management Plan for Dehesa nolina.
| Action | Statement | Action status | Projects |
|---|---|---|---|
| IMP-1 | Submit metadata, management effectiveness datasets, analyses, and report to the MSP Web Portal. | waiting for precedent action |
| Criteria | Deadline year |
|---|---|
| Effectiveness of High Priority Management Actions Determined | 2021 |
| Threat Name | Threat Code |
|---|---|
| Altered fire regime | ALTFIR |
| Climate change | CLICHN |
| Invasive plants | INVPLA |
| Loss of connectivity | LOSCON |
Management units: 3
In 2019, begin preparing a section for Dehesa nolina in the MSP Seed Collection, Banking and Bulking Plan to preserve genetic diversity and rescue occurrences in case of catastrophic disturbance. The plan should incorporate best science and management practices (e.g., Wall 2009, KEW 2016) and provide guidelines for collecting and storing seeds over the long term at a permanent, established conservation seed bank (e.g., Institute for Conservation Research Native Plant Seed Bank, Rancho Santa Ana Botanic Garden Seed Conservation Program) and for providing a source of seeds for management purposes. The plan should include recommendations for: collecting and storing seeds for conservation banking; management oriented research; rescuing occurrences after catastrophic disturbances; and seed bulking and out-planting to augment extant occurrences or to establish new occurrences with consideration of genetic implications for population sustainability.
| Action | Statement | Action status | Projects |
|---|---|---|---|
| PRP-1 | Consult the San Diego County Rare Plant Working Group working group made up of plant ecologists, geneticists, rare plant experts, land managers, restoration practitioners, seed banking and bulking practitioners, wildlife agencies, and other stakeholders to provide input and recommendations for Dehesa nolina in the MSP Seed Collection, Banking and Bulking Plan. | some occurrences are in progress | |
| PRP-2 | Prepare a seed collection plan to collect seeds over multiple years, collect seeds several times within a season, accumulate seeds across populations, and to sample among habitats and ecological niches. Include guidelines for collecting and storing seeds along maternal lines from small occurrences (<1,000 plants) and to provide propagules to be used in management experiments, enhancement of existing occurrences, and establishment of new occurrences. | some occurrences are in progress | |
| PRP-3 | The seed collection plan should include guidelines for collecting seeds from occurrences of sufficient size to accommodate harvest and based on genetic studies as available. Include provisions for collecting seed from unconserved populations planned for development. | some occurrences are in progress | |
| PRP-4 | Include protocols and guidelines for collecting voucher specimens and submitting to the San Diego Natural History Museum (McEachern et al. 2007). | some occurrences are in progress | |
| PRP-5 | Include guidelines for testing seeds for viability and to obtain information on dormancy and germination rates. | some occurrences are in progress | |
| PRP-6 | Submit project metadata and MSP Seed Collection, Banking and Bulking Plan to the MSP Web Portal. | some occurrences are in progress |
| Criteria | Deadline year |
|---|---|
| By 2019, Completed Dehesa Nolina Section in MSP Seed Collection, Banking and Bulking Plan | 2021 |
| Threat Name | Threat Code |
|---|---|
| Altered fire regime | ALTFIR |
| Climate change | CLICHN |
| Invasive plants | INVPLA |
| Loss of connectivity | LOSCON |
Management units: 3
In 2020, begin implementing high priority actions for Dehesa nolina in the MSP Seed Collection, Banking and Bulking Plan to collect and store seeds at a permanent seed bank and to provide propagules as needed for management oriented research, existing population enhancement and establishment of new occurrences.
| Action | Statement | Action status | Projects |
|---|---|---|---|
| IMP-1 | Bulk seed at a qualified facility for enhancement, expansion, establishment or transplantation projects using seed from genetically appropriate donor accessions in the propagation seed bank collection. | waiting for precedent action | |
| IMP-2 | Maintain records for collected seed to document donor and receptor sites, collection dates and amounts. Submit seed collection, storage and bulking data to the MSP Web Portal. | waiting for precedent action |
| Criteria | Deadline year |
|---|---|
| Dehesa Nolina Seed Collected for Banking and Bulking Within 2 Years Post-Fire and =1 High Priority Action from the MSP Seed, Collection, Banking and Bulking Plan by 2024 | 2021 |
| Threat Name | Threat Code |
|---|---|
| Altered fire regime | ALTFIR |
| Climate change | CLICHN |
| Invasive plants | INVPLA |
| Loss of connectivity | LOSCON |
Management units: 3
In 2017, begin field research into soils and habitat relationships and conduct habitat suitability and climate change modeling for Dehesa nolina and other edaphic endemic plants to better understand habitat requirements and to identify and prioritize geographic areas important for connectivity, restoration, and range shifts due to climate change and other threats.
| Action | Statement | Action status | Projects |
|---|---|---|---|
| RES-1 | Test soils at potential expansion sites and compare to occupied reference sites to determine site suitability based on soils. | In progress | Enhancing the Resilience of Edaphic Endemic Plants |
| RES-2 | Prepare habitat suitability models under current environmental conditions and for different scenarios of climate change to delineate potential future habitat. | In progress | Enhancing the Resilience of Edaphic Endemic Plants |
| RES-3 | Collect covariate data on vegetation composition and cover (alliance and association-level mapping), soils, invasive plants and other threats for selected populations. | In progress | Enhancing the Resilience of Edaphic Endemic Plants |
| RES-4 | Prioritize locations for conservation, management, and future surveys based on predicted distributions and environmental correlates. | In progress | Enhancing the Resilience of Edaphic Endemic Plants |
| RES-5 | Submit project metadata, monitoring data, habitat models, analyses, and report to MSP web portal. | In progress | Enhancing the Resilience of Edaphic Endemic Plants |
| Criteria | Deadline year |
|---|---|
| Refined Models and Prioritized Future Survey Locations for Dehesa nolina by 2018 | 2021 |
| Threat Name | Threat Code |
|---|---|
| Altered fire regime | ALTFIR |
| Climate change | CLICHN |
| Invasive plants | INVPLA |
| Loss of connectivity | LOSCON |
|
Brachypodium Control
This project used a science-based, experimental approach to develop treatment and restoration
strategies for the emerging invasive grass, Brachypodium distachyon (Brachypodium), on
conserved lands in southern San Diego County, CA. Phase I (2013-2015) included conceptual
models to inform experimentally-based treatment and restoration strategies; experimental
treatments (dethatching, herbicide, mechanical removal), monitoring, and seed collection,
bulking, and outplanting. Treatments continued in Phase II (2016-2017), using the most
effective management strategy (herbicide). See the Phase I and II reports for study results and
Best Management Practices (BMPs) for Brachypodium control. Herbicide is the most effective
treatment for controlling Brachypodium but timing of treatment is critical and multiple
treatments may be required in a single year, depending on rainfall and temperature. Herbicide
treatment of forbs becomes increasingly important as cover of Brachypodium and other
nonnative grasses decrease. Dethatching improves treatment effectiveness and stimulates the
soil seedbank (if present). The experimental design was coordinated with SDMMP and the City
of San Diego, and results may contribute to a regional analysis of Brachypodium control across
multiple sites, habitats, and microclimates.
|
|
Covered and Invasive Species Management: Crestridge Ecological Reserve and South Crest Properties
This was a two year, TransNet-funded study (#5001586) on Crestridge Ecological Reserve and South Crest properties. Both properties support MSCP covered species and sensitive habitats, and function as critical landscape linkages between the northern and southern MSCP. Surrounded by residential development and heavily impacted by the 2003 Cedar Fire, these properties are subject to ongoing invasive plant issues. Specific task actions included invasive plant and covered plant species mapping and risk assessment s, invasive plant control and experimental studies, and development of an early detection invasive control plan. This project was partially funded by SANDAG TransNet EMP Land Management Grant #5001586.
|
|
Dehesa Nolina Conservation and Management Strategy
The Conservation Biology Institute developed a science-based Conservation Vision and
Management Strategy for Dehesa nolina in San Diego County. The Conservation Vision
assessed the distribution, status, and threats of populations on conserved lands through data and
literature reviews, site visits, and interviews with land managers. Products included spatial data
layers, an updated matrix of threats and stressors, management recommendations, and prioritized
populations for management.
The Management Strategy focused on preserve-level management, using the existing Dehesa
nolina population on the South Crest Preserve to test/refine management techniques, including
species augmentation (seed collection, contract growing of plants, out-planting) and erosion
control. These actions also benefitted Dudleya variegata (variegated dudleya) and sensitive
native grassland habitat. These management actions complemented other Transnet-funded
management on South Crest; techniques refined in this project are applicable to other conserved
populations in the region. Project partially funded by SANDAG TransNet EMP Land Management Grant #5001763
|
|
Enhancing the Resilience of Edaphic Endemic Plants
The Management Strategic Plan for San Diego County requires prioritization and management for edaphic endemic plants, including the five rare plants addressed in this study. These species face low genetic diversity due to reduced population sizes, geographic isolation, and loss of pollinators. To enhance the resilience of these species across their ranges, we must manage threats to increase population sizes, identify potentially suitable habitat to connect existing populations, find or restore new populations, and provide opportunities for shifting distributions due to climate change.
This study identifies and describes geographic areas that support the five edaphic endemic species and their habitat in a design that enhances resilience and provides opportunities for shifting distributions. We developed conceptual models to inform field studies and management, refined soils and vegetation attributes, and assessed regional population structure and threats. We used results to suggest prioritized locations for surveys, management, potential translocation, and additional conservation or acquisition. Project partners (U.S. Geological Survey and San Diego Management and Monitoring Program) modeled suitable habitat for the target species under current and future climate scenarios; we reference models as appropriate.
|
| File name | Lead Author | Year | Type |
|---|---|---|---|
| Biological Monitoring Status Report for Crestridge Ecological Reserve and South Crest Properties | 2012 | report | |
| Conservation Vision and Management Strategy for Dehesa Nolina (Nolina interrata) in San Diego County, CA | 2015 | report | |
| County of San Diego MSCP Monitoring Summary Report January 1998 - June 2007 | County of San Diego | 2007 | report |
| Dehesa Nolina (Nolina interrata) and Variegated Dudleya (Dudleya variegata) Augmentation | 2016 | report | |
| Enhancing the Resilience of Edaphic Endemic Plants | 2018 | report | |
| Final Report Covered and Invasive Species Management: Crestridge Ecological Reserve and South Crest Properties | 2012 | report | |
| Management Strategic Plan (MSP) 2015 Monitoring Protocol for Rare Plant Occurrences on Conserved Lands in Western San Diego County | San Diego Management and Monitoring Program | 2015 | report |
| San Diego Rare Plant Monitoring Plan: Fiscal Year 2011 | Greer, Keith; McEachern, Kathryn; Tracey, Jeff | 2011 | report |
Restricted distribution in southern foothills of San Diego County and northwest Baja California [1). In Baja, three small populations reported between border and Ensenada. Elevation range 230-700m [2). In San Diego, Reiser (1994) reported from Dehesa School, McGinty Peak; Sequan Peak; also Barber Mountain, Jamul Butte, Wood Valley, Pat's Mountain, and on west side of Sloane Canyon on The Mesa. In the MSPA, occurs in MU3 (McGinty Mountain Preserve, San Diego National Wildlife Refuge, South Crest Properties, Sycuan Peak Ecological Reserve; [4]).
SE; Proposed for federal listing
Typically found in rugged terrain dominated by southern mixed chaparral or chamise chaparral in areas with these nutrient poor clay soils [1,3]. Known only from gabbro substrates (rich in ferro-magnesium minerals; [2]).
Perennial herb; Ruscaceae family [6]. Dice (1988) concluded N. interrata distinct from Parry’s beargrass (N. parryi), Peninsular beargrass (N.cismontana), and Bigelow’s nolina (N. bigelovii) and N. wolfii (N. wolfii reduced to synonomy with N. parryi); referred to these as N. bigelovii- N. parryi complex. Distinguished from the other Nolina in California by lack of aerial stems, rosettes with 45 or fewer finely serrate leaves, flower stalks under 1.6 m tall; distinguished from Yucca species by lack of a rigid spinose (spiny) leaf tip and leaves with shredding margins [1].
Forms clusters of rosettes and has flower stalks up to 1.6 m tall [1]. Reproduces sexually and asexually (from underground stems; [1]). Nolina can take long period from germination to attain sufficient size for flowering, although two male plants of this species flowered in 3 years or less based on collected seeds [2]. Flowers profusely after fires [1]. Population estimated at ~9,000 plants within the 15.6 km2 range in the U.S. [1]. Morphology helps survival during fire (subterranean buds and above-ground apical buds protected by dense crown of overlapping succulent leaf bases); mass-flowering events observed 1-2 years following fire, although seed predation may diminish productivity from these events [2].
Blooming period June-July [6].
Dioecious (separate male and female plants); does not flower every year; asexual reproduction may compensate for this [1]. Insect visitors to the N. bigelovii- N. parryi complex primarily bees (honey bees, solitary native bees; [2]). Seeds disseminated by disarticulation of pedicel, with wind and rains presumed to aid in the process. Seedling recruitment in N. bigelovii- N. parryi complex considered rare due to seed predation [2].
Fire suppression leading to fuels accumulation increases vulnerability to fire because of increased fire intensity leading to increased risk of mortality and seed bank destruction [1]. Frequent fire can prevent plants from reaching reproductive maturity. Threatened by residential development, vehicles, altered fire regimes, and horticultural collecting; possibly threatened by non-native plants [6].
Because of affinity for clay soils, often associated with other rare plant species [1]. Dice (1988) notes population sizes may have been overstated in some instances; provides an example of a small population with 2000 rosettes he estimated to represent 50 individuals based on counting discrete clusters of rosettes separated by at least 0.5m, but in a preliminary genetic analysis found each cluster was genetically identical at 15 loci.
[1] USFWS (U.S. Fish and Wildlife Service). 1998. 50 CFR Part 17: Endangered and Threatened Wildlife and Plants; Withdrawal of Proposed Rule to List Nolina interrata (Dehesa beargrass) as Threatened. Federal Register 63(197):54972-54974.
[2] Dice, J.C. 1988. Systematic Studies in the Nolina bigelovii-N parryi (Nolinaceae) Complex. A thesis presented to San Diego State University. 203 pp.
[3] Reiser, C.H. 1994. Rare Plants of San Diego County. Aquafir Press, Imperial Beach, CA. Available online: http://sandiego.sierraclub.org/rareplants/
[4] MSP-MOM. 2014. Management Strategic Plan Master Occurrence Matrix. http://sdmmp.com/reports_and_products/Reports_Products_MainPage.aspx
[5] USFWS (U.S. Fish and Wildlife Service). 1997. 50 CFR Part 17: Endangered and Threatened Species; Review of Plant and Animal Taxa; Proposed Rule. Federal Register 62(182):49397-49411.
[6] CNPS, Rare Plant Program. 2014. Inventory of Rare and Endangered Plants (online edition, v8-02). California Native Plant Society, Sacramento, CA. Website http://www.rareplants.cnps.org [accessed 17 June 2014].