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A related threat is how climate change will influence the environmental conditions of the Presidio. All models indicate that northern California will experience warmer temperatures (Cayan et al. 2008, Miller et al. 2003, Hayhoe et al. 2004, Knowles et al. 2006), and more recent studies suggest that rainfall will decrease on average, but in a pattern of quite variable yearly rainfall, with some extremely wet years, and with series of droughts (Cayan et al. 2008). What is not known yet, is how climate shifts will influence oceanic currents, and as a consequence, the frequency of summer fog along the coast. Other issues that have not been given substantial consideration in previous recovery plants involve mutualists that the Presidio manzanita may require. One group of important mutualists includes pollinators. Previous plans have suggested mixed populations of the Presidio manzanita along with the Franciscan manzanita (A. franciscana); mixed populations with overlapping but different flowering times would provide additional resources for appropriate pollinators. A second group of mutualists would be mycorrhizal fungi. Adding these types of organisms to soil of cloned plants just prior to out-planting, or just afterwards, may increase survival greatly, as these organisms not only improve nutrition of host plants in poor soils, but also improve survival of droughts through the summer (Horton et al. 1999). 27 Figure 13. Presidio clone from the Yerba Buena serpentine site. A). The plant is healthy, but exhibits a number of dieback areas due to interactions with other plants. In the upper left, a coastal scrub species (Baccharis pilularis) overtopping the shrub. In the center of the manzanita, soap-plant has shaded out much of the manzanita branches. Other species are also involved in this example. B). A close-up of the same shrub shows more detail of the individual associated plants and their impact on the prostrate manzanita clone. Photos by V.T. Parker. A final group of potential mutualists involve seed predators that may cache seeds of manzanitas. These animals normally consume a large proportion of each year’s crop of seeds. Because they compete with one another for seed, they bury (or cache) seeds into holes roughly 5 cm across and over 5 cm deep (Borchert et al. 2003). These types of caches are known for a number of species of manzanitas (Tevis 1953, Keeley and Zedler 1978, Parker, unpublished data). What is important about these seed predators is that their burying activity inadvertently provides a fire adaptation for manzanitas (Parker, unpublished data). Current models of manzanita management assume a great ‘immaturity risk’ to seed bank development. Thus, the original Presidio manzanita should have a seed bank sufficiently deep, but the clones at the Yerba Buena site would still be too young (if they were producing fruit) to have developed any substantial seed bank. This indicates that effective management of these species may require effective management of animal communities within chaparral. Animal caching of Arctostaphylos seeds may shrink the period of time currently considered ‘immaturity risk’ due to more rapid burial of seeds to safe depths. 28 Figure 14. Changes associated with the Yerba Buena and WWII Memorial sites over the last 35 years. Observable are changes such as the removal of landfill associated with the Yerba Buena site, some tree removal. Photos courtesy of Californiacoastlines.org. Management Recommendations for Arctostaphylos montana subsp. ravenii in the Presidio IV. A. Current Management for Arctostaphylos montana subsp. ravenii: Plans and activities: Considerable efforts have resulted in improvement of the potential for the Presidio manzanita to recover over the last 35 years (Figure 14). Current management practices follow the 2003 Recovery Plan. The 2003 Recovery Plan incorporated recommendations from the 1984 Recovery Plan and the 2001 Vegetation Management Plan. Specific recommendations from the 2003 Recovery Plan are in Table 4. The principal recommendations listed at that point were: 1) To protect the original individual, including removing of trees or other plants that might shade or otherwise threaten the plant. This recommendation has been followed, including the removal of trees near the Presidio manzanita. The original plant and clones are frequently monitored (see Appendix 2). 2) Increase the number of populations. 29 The 1984 plan recommended 5 separate populations with at least 20 individuals each. In 1987, the Presidio and GGNRA propagated 168 cuttings and yielded about 50 survivors. Several cluster of clones were planted (mother plant, Triangle, Yerba Buena serpentine, West Crissy Bluffs, Inspiration Point). Additional clones were planted in 1988 at the site with the mother plant. A cluster of cloned individuals have been added around the original mother plant. Of the original plantings, some 8 or 9 clones have established. At the triangle, one plant of the original plantings remains, and at the Yerba Buena serpentine site, seven individuals remain. Other plantings met with failure to establish new individuals. An inventory of all potential planting sites within the Presidio and outside the Presidio was suggested. Potential locations were discussed in the 2003 Recovery Plan. The 2003 Recovery Plan recommends the same number, and suggests as a recovery criteria that there be 5 separate populations outside the Presidio and 2 within the Presidio. 3) Based on the fact that seedlings were successfully germinated from isolated clones at UC Botanic Garden, a third objective was to restore sexual reproduction and regeneration of the Presidio manzanita. To achieve this, two mechanisms were suggested. One was, if the seedlings from the UCBG plants proved to be from selfing, then they could be cloned and new populations established. A second mechanism was to use the process of introgressive hybridization to develop sufficient genetic variation in additional individuals that spontaneous sexual reproduction could occur. Genetic studies conducted at SFSU indicate that several of the seedlings from UCB resulted from selfing (2000.191, 2000.195, 2000.196, and ‘unlabeled’). The other seedlings were either clearly the result of outcrossing or were sufficiently ambiguous as to be suspected. 4) Develop populations that incorporated A. franciscana (Franciscan manzanita) as well as the Presidio manzanita. Now that an individual of A. franciscana has been found within the Presidio, this should be more easily achieved and accepted. Interim Recovery Criteria from the 2003 Recovery Plan involved 1) habitat stabilization, 2) propagation of seedling and clonal stock, 3) establishment of new daughter clones on Presidio serpentine bluff sites, and 4) investigation of taxonomic relationships and reproduction. Habitat and population stabilization within the Presidio is an ongoing process, but apparently there have been no loss of individuals since the plan. Propagation of seedling and clonal stock is ongoing. Now that selfed seedlings have been identified, this process can proceed. There have yet to be additional populations established at other sites. Taxonomic relationships among the Presidio manzanita and other species have been completed, although not all information is published yet (Parker et al. 2007, Keeley et al. 2007, Vasey and Parker 2008, Parker et al. 2009). The Presidio manzanita is a tetraploid species that appears to be of allopolyploid origin, meaning that it has genes from multiple potential parent species, rather than resulting from polyploidization within a single lineage. The possible parents include A. franciscana and A. hookeri, as well as having other alleles associated with maritime species from the Santa Cruz Mt to Monterey Bay region (Parker, unpublished). 30 B. Management Recommendations The following recommendations follow the 2003 Recovery Plan as modified by current information. 1). Protect and manage the original plant and the clones surrounding it. 2). Increase the number of populations. 3). Create populations with the potential for sexual reproduction by intermixing seedling clones with parent clones. 4). Investigate additional serpentine sites within the Presidio, outside the Presidio, and in other locations. 5). At some sites, mix populations of seedling clones, parent clones, and clones from different A. franciscana individuals. 6). Continue with ongoing management practices involving removal of introduced species or native species whose growth results in significant dieback of planted manzanitas. 7). Research different aspects of the Presidio manzanita, including seed banks, controlled breeding experiments, and phenology studies. These recommendations build upon the previous recovery plans and expand them or modify recommendations based upon new information. A comparison of these recommendations with those of the 2003 Recovery Plan is in the following table (Table 4). 1). Protect and manage the original plant and the clones surrounding it. At this location, a number of introduced and native species interact with the Presidio manzanita resulting in diebacks of different parts of the plant. This seems especially true with Chlorogalum (soapplant), and in some locations with other species. It may be necessary to monitor these sites and remove some of the Chlorogalum individuals as they get too large. Most importantly, conservative management of the original plant continues to seem prudent (Table 4, left side, #1, 3, 4). 2) Increase the number of populations. It is still critical to have as many populations as possible due to unforeseen future events. This includes populations both inside the historic range, and outside the range as well (Table 4, left side, #5) Within the historic range, a number of potential sites have been located. These include the ridge above Crissy Field, downslope of Inspiration Point, and outcroppings of serpentine along the bluffs overlooking the Golden Gate, from Fort Point to the Yerba Buena outcropping. Table 4. Comparison of recommendations between this plan and the 2003 Recovery Plan. Previous Recommendations (2003 Recovery Plan) Recommendations in this plan 1. Management of areas around the Presidio manzanita 1. Management of areas around the Presidio and any outplantings to suppress invasion of nonnative manzanita and any outplantings to both suppress vegetation (p. 69). native or nonnative vegetation that might result in dieback of plants. 2. The Presidio Trust needs to plan for future endangered species recovery, starting with obtaining complete inventories of outcropping and near-surface serpentine subsoils of the Presidio (p. 73). 2. Given that this information appears to exist now, no specific recommendations were made regarding inventories of serpentine soils; planning for future endangered species recovery also appears to be 31 ongoing. 3. The Presidio Trust needs to initiate an outreach program to schools, horticultural, conservation and community organizations (p. 73). 3. While not specifically recommended, this should accompany any activity and be an ongoing process to bring the public into conservation and management. (within the specific recommendation section) 4. Continue to protect existing clone conservatively (p. 75). 5. Increase number of independent populations of the original clone at various locations. (Both this report and the 1984 report recommend at least 5 separate populations). Under recovery criteria, the report suggests 5 spontaneously reproducing variable populations outside the Presidio and at least 2 within the Presidio, with individuals increasing in size over a 30 yr period (p. 75). 6. Restore sexual reproduction and regeneration (p. 7576). 4. Continue to protect the existing clone conservatively, by that, do not plant other individuals or species near it until other populations are proven and results evaluated. 5. Increase the number of independent populations, some strictly A. montana subsp. ravenii. but most combining both the Presidio and Franciscan manzanita. Specific numbers of populations are not specified, but increasing the number of independent populations should be a continuing goal. 6. Given that many of the seedlings raised at UC Botanical Garden are the result of selfing, they should be cloned and all new populations should be intermixed combinations of these different individuals. 7. Restore its potential natural ecological interactions with native associated species including A. franciscana (p. 75-76). 7. Incorporating additional natives is a lower priority, but has the advantage of supporting a more viable insect and rodent community, on both of which manzanitas depend for pollination and seed dispersal. 8. Restore populations in interior San Francisco as well and including A. franciscana in some of these restorations (p. 76). 8. Given the limited number of adequate sites within the Presidio, restoring large numbers of populations will require utilizing other locations within San Francisco. 9. Generate new seedling-grown plants resulting from self-fertilization under controlled conditions (p. 77-78). 10. Potentially develop a breeding program using close relatives and backcrossing to generate more genetic diversity (p. 78). 9. Generating new individuals under controlled conditions is discussed under suggested research. 11. Develop a genetic management plan describing the crossing program and any reintroduction (p. 79). 10/11. Developing a breeding program using close relatives and then backcrossing is not recommended at this time. There may be sufficient variability among the seedlings to establish a reproductive population. 12. Establish research priorities for increasing genetic and ecological diversity in restored populations. Some of these additional sites for populations should include sites on the ocean/Golden Gate side of Lincoln Blvd. This would permit the opportunity of experimental burns in the distant future. These populations should combine different cloned individuals of A. montana subsp. ravenii, and could also be intermixed with different clones of A. franciscana (see next recommendation). Figure 14. Serpentine bluffs north of Yerba Buena (A.) and 30 yrs of minor changes near the bridge (B., C.). Pictures courtesy of Californiacoastlines.org. 32 This should include attempting to establish clones at botanic gardens outside of the Bay Area, for example, the Santa Barbara Botanic Garden or the Rancho Santa Ana Botanic Garden. Another simple concept might be to purchase serpentine rock and soil and establish a site outside the 33 Presidio, for example on the slopes above Rodeo Lagoon in the GGNRA to create another artificial site. 3). Create populations with the potential for sexual reproduction by intermixing seedling clones with parent clones As UC Botanic Garden and the Presidio Nursery produces clones from the selfed seedlings, one practical objective for management should to create multiple populations within the Presidio containing mixes of parent and seedling clones. Another will be discussed under potential research objectives. Within the Presidio, mixed populations should be established on both sides of Lincoln Ave. On the ocean/Golden Gate side of Lincoln Avenue, there are considerable serpentine outcroppings. These plants would not only help to stabilize some of the bluffs, but planting mixtures of clones on this side would permit a direct test of recovery in the distant future. If these plants have sufficient genetic diversity and begin setting viable seed, then in the future, prescribed burns could be used to test the viability of these populations, killing off the adults, and stimulating the seeds from the persistent seed bank. This is really the basis for recovery for a chaparral plant like the Presidio manzanita. Some of these populations could also be intermixed not only with diverse clones from the Presidio manzanita, but also with genetically diverse clones from the Franciscan manzanita. 4). Investigate additional serpentine sites within the Presidio and outside the Presidio (Table 4, left side, #2, #8). This may require modification of some habitats by removal of current vegetation or leftover construction from the military. If the sites have trees or other vegetation, gradual conversion of the site may be more practical than a rapid change in condition if it is in public view (see recommendation #3 in the 2003 Recovery Plan, Table 4). Some sites within the Presidio could be better optimized by adding crushed serpentinite rock like the Log Cabin area, or in sites lacking serpentine. It may be that serpentine areas will have to be created given the loss of habitat to golf courses and anthropogenic forests that will be difficult to modify or restore. 5). At some sites, mix populations of seedling clones, parent clones, and clones from A. franciscana (Table 4, left side, #5, 6). This objective is in keeping with the 2003 Recovery Plan as well. No or little genetic transmission is likely between the species because they differ in ploidy level. Given that A. franciscana already has alleles represented in the Presidio Manzanita, it might be difficult to determine introgression in any case. More important, the species may differ in the timing of flowering, and those differences not only limit the potential for introgression, but more importantly, can support the enhancement of potential pollinator populations. Pollinator populations are critical for long-term seed and fruit development and steps should be taken to enhance their populations. 6). Continue with ongoing management practices involving removal of introduced species or native species whose growth results in significant dieback of planted manzanitas (Table 4, left side, #1, 7). I list this activity separately because of the critical nature of this management action. In areas in which there is some soil development, many different species can establishment within or near plantings of these prostrate manzanitas and easily overtop them. This would defeat attempts to establish new populations or maintain current populations. 34 7). Research different aspects of the Presidio manzanita, including seed banks, controlled breeding experiments, and phenology studies (Table 4, left side, #9, 10, 11, 12). In addition to attempts to increase the number of populations of the Presidio manzanita, research needs to be conducted into aspects of increasing genetic diversity as well as in increasing the ecological integrity of the restored populations. Given the recent discovery of Arctostaphylos franciscana within the Presidio, the context of recommendations for the Presidio manzanita has changed. Now that another rare plant will be receiving a similar priority for recovery, the total number of potential sites for either the Presidio or Franciscan manzanita has halved. Nonetheless, the principal recommendations are not altered. The list below is provided as further ways of insuring recovery of the Presidio manzanita by either increasing the genetic diversity of its populations or by increasing the resilience and efficiency of the maritime chaparral system within which it lives. These are considered potential research directions for the Presidio Trust that may increase the potential for full recovery of the Presidio manzanita. 1. Research studies of the persistent soil seed bank of Arctostaphylos montana subsp. ravenii. This species has a persistent soil seed bank. The history of the plant suggests that it may well have been isolated for at least a century. The missing information includes whether there were any additional individuals nearby that hadn’t been observed and whether there is much of a developed seed bank beneath the plant. If we assume there is at least a small seed bank, then there could be additional genetic variation available from other parents who no longer exist. The seed banks of Arctostaphylos species, however, are difficult to germinate. They do seem to require chemicals from smoke, but additional requirements also appear to be necessary, as smoke-induced germination yields only low percentages. Thus, stimulating the soil seed bank beneath the mother plant should be approached conservatively. A first step alternative is to support research into germinating seeds from soil seed banks of closely related species, using their seed banks until there has been some success or optimization of the process. Thus, this recommendation is to develop methods first on other species (e.g., Arctostaphylos montana), and only later try small soil samples from beneath the mother plant. Goal is to increase the number of potentially different genetic individuals using the seed bank as the source. 2. Another approach to increasing some genetic diversity involves assessing inbreeding potential. The recommendation is to approach this quantitatively as a research project. The Presidio manzanita is a tetraploid species, and they often exhibit lower rates of inbreeding. The project should focus on a set of tetraploids including the Presidio manzanita as well as A. montana subsp. montana, and a few additional tetraploids (preferably non-sprouting tetraploids like A. bakeri or A. manzanita). As well, the inbreeding project should include several diploid species, for example, A. franciscana, and other regional diploids (A. montaraensis, A. canescens, A. virgata, etc). 35 Goal is to permit evaluation of inbreeding potential for the Presidio manzanita both quantitatively and from the perspective of ploidy level. 3. Now that additional individuals of the Presidio manzanita have been raised from seed, an experimental crossing program should be initiated. In this program, hand crosses among individuals would be made (including reciprocal crosses of using each individual as a pollen parent). Control crosses would involve hand crossing each individual. To evaluate the recovery potential of the Presidio manzanita in the context of other species, this project should also perform similar experiments with other species, both diploid and tetraploid. First, conduct experimental crosses of seedling x parent and seedling x other seedling. Results should be compared with crosses of seedling x self, and parent x self, to investigate whether the seedlings and parent have sufficient genetic variation among them to produce spontaneous successful sexual reproduction. For each pair of individuals used in crossing experiments, each individual should be used both as the pollen donor and pollen recipient in separate crosses. Inflorescences should be bagged to prevent other pollen from modifying results. These experiments should be replicated multiple times (multiple years) to account for variation in climate, condition of plants, viability of experimental pollen. If there is greater fruit formation with crosses among separate genetic individuals compared to selfed crosses, then the indication would be that spontaneous sexual reproduction should occur among plants in populations created in the field. Controls would be tests on other tetraploid and diploid species (listed in previous paragraph). If there are no significant differences, then introgressive hybridization may be required in the future (see 2003 Recovery Plan). Goal is to assess the reproductive potential of the Presidio manzanita given the current set of genetic variants 4. Given that the 2003 recovery plan and this recovery plan propose mixed plantings of A. franciscana with the Presidio manzanita, evaluating the potential for genetic exchange is another experimental direction that could be performed, hand-crossing reciprocally, individuals of both species. Crosses should be performed of the Presidio manzanita x Franciscan manzanita under controlled conditions, using each individual as both a pollen donor and pollen recipient in separate experiments. This would assess the potential for gene flow between these species of different ploidy levels. Another important recent discovery within San Francisco is a new (although currently undescribed) subspecies of A. bakeri, another tetraploid serpentine endemic. Clones should be made of this species as well and crossing studies among species performed as this might be another species that could be incorporated into mixed populations in the future. 5. Another recommended study would involve quantifying the phenology and the pollination ecology of A. montana subsp. ravenii, A. franciscana, the undescribed A. bakeri subspecies, and other common shrubs in the Presidio maritime chaparral such as the prostrate Ceanothus thyrsiflorus. The goal of this study is understand how to create combinations of species so that there is a continuing flowering period for the community 36 as a whole. In that way, a larger and more persistent pollinator community would be possible, maximizing the reproductive potential of any of the species involved. This would increase the overall integrity of the system. While relatively pure stands of the Presidio manzanita or stands mixed with the Franciscan manzanita should be a short-term goal, on the longer term, mixing in additional species to support a broader pollinator and rodent community will also be critical. 6. Similarly, additional studies should experimentally investigate techniques of outplantings. This would involve tests manipulating combinations of mycorrhizal mutualists and maintaining different levels of soil moisture through the first or first and second years. Several practices need to be experimentally investigated with respect to planting clones in the field. One of these is the timing of plantings and what soil moisture levels to maintain during the summer drought. Because these are potted plants from cuttings, and not seedlings establishing post-germination, it is critical to plant these cuttings just before or after the first fall rains. Experimental plots should be set up with soil moisture probes. Plots could be permitted to dry to different extents before watering. Plants also may need to be watered in during the fall between initial rains. Quantification by using soil moisture probes will establish which levels of soil moisture are tolerable to small plantings, determining if and when plantings should be watered during the dry season. This should permit a greater degree of success in future plantings. Keeping the soils sufficiently dry is just as much an objective of these studies as is keeping sufficient moisture in the soil; manzanita roots are not tolerate to extended periods of soil moisture indefinitely. A second practice that should be investigated is the use of mycorrhizal fungi to aid in plant establishment. Because of the establishment of fungal diseases in a number of Bay Area counties (such as sudden oak death), it is not advisable to transport soil from beneath stands of A. montana on Mt Tamalpais, for example, to provide inoculum. It is possible, however, to collect fruiting bodies of mushrooms from beneath these stands and to create slurries to add to potted plants or to plantings as a way to add potential mycorrhizal fungi. Given that the great majority of fungi involved in mycorrhizae do not fruit very often, it might be necessary for this process to occur across multiple years and multiple serpentine chaparral sites that contain manzanitas. Plants experimentally planted could receive supplemental mycorrhizal additions (from Mt. Tamalpais mushrooms beneath A. montana as an example) or have these supplements withheld to determine if plants survive better or grow better over a few year period. Summary: The long-term goal should be to have multiple populations in a variety of locations. These should incorporate mixtures of species in the long run (such as A. franciscana) in order to produce whole ecological communities that can maintain themselves. That would include the plant component, and the soil community, the pollinator community, and the seed predator/caching community. Once some populations are established with mixes of individuals 37 that appear to be spontaneously reproducing, it might be possible to practice prescribe burning on some of these populations after they have been established over 20-30 years to increase the potential genetic component of these populations from seedling establishment. Seedlings will have resulted from crosses among the different genetic individuals continuing the process of mixing up alleles resulting in additional phenotypes. At that point, reproductively successful populations will have been established. 38 APPENDIX 1 - Summary of the history of the Presidio manzanita ~1940 ~1952 1958 1961 1976 1979 1980 1981 1984 1985 1985 1986 1987 1987 Compiled by Mark Frey (last updated 11/26/08) Laurel Hill Cemetery and Masonic Cemetery populations destroyed by development. A third population at Mount Davidson was destroyed sometime between 1923 and 1962.1 Mother plant found by Peter Raven1 WWII memorial built1 James Roof took 4 cuttings from the mother plant to what is now East Bay Regional Parks Botanic Garden2 Proposed for ESA listing1 Listed as Endangered1 20 cuttings rooted at UC Botanical Garden and grown. One planted in serpentine display bed, the remaining 19 potted up for open and controlled pollination experiment16 Sue Smith met with representatives of the three Botanic Gardens in the area and Jim Eldredge. They decided to remove 2 large conifers. The trees were remove din the fall.20 Recovery Plan Road work done on Lincoln2 Army plants 140 Arctostaphylos uva-ursi but they were later removed2 8/14/86: Army removed four pines. 22 9/24/86: CNPS removed duff and one small cypress.22 January: 168 cuttings were collected. Roger Raiche (UC Bot.) took 61 and Philip McMillan-Browse (Saratoga Horticulture Foundation) took 107. At the same time it appears that 2 went to Strybing and some went to the Fort Funston Nursery.2,4 December: 50 rooted cuttings. Saratoga retains 6.2, 23 Strybing gets 2.2, 23 Maybe from the Saratoga collection. 8 planted near mother plant by Peter Straub, he periodically watered and maintained them over the next two to three years.2,4,7,18, 23 22 planted at Yerba Buena by GGNRA staff.2 2 at IP by Peter Straub.2 They were ~10 feet from the Quarry Road trail.23 These plants survived for several years until unauthorized mountain bike use caused their demise.18 6 (or maybe 4) at West Crissy Bluffs, below Lincoln, near the corner of Lincoln and Crissy Field Ave. by Peter Straub.2, 23 These plants did not survive.18 12 planted within the WWII memorial site itself, right near the path.23 Three pines may have been removed.2,23 This work was done by CNPS, the trees were ~30 ft tall.19 It seems likely that these may be the same trees that were 39 1988 1988 alive2 1988 1991-1992 1994 1994 1995 1995 1996 1996 1996 1996 1998 1998 1998 ~1998 1999 2003 2003 2003 2000 2002 2003 plant)11 ?-2003 actually removed by the Army 8/14/86. The Reference 22 notes that the plan was to removed three pines but a four was added at the last minute. Seeds collected in June and July by Terri Thomas. UC Bot. Garden took them. They treated 38 seeds and one germinated.4, 6 They have since then died.16 Clone status: 7 clones near mother plant, 22 at Yerba Buena, no other clones 2 more clones planted near mother plant, 4 clones at triangle, 6 “near Lincoln Blvd, south of the parent plant”, 3 clones at IP2 Fencing and signage installed2 Clone status: 10 clones near mother plant, 12 at Yerba Buena, 2 at triangle5 One IP clone alive but very small (I can’t find my reference). In 1996 this plant was not noted8 and in 1998 it was not found9. UC Bot has clones from collections in 1980 and 1987. UC Botanical Garden collects over 4500 berries from open pollination and several hundred from controlled pollination at their site.16 Two pines removed (I can’t find my reference). Clone status: 11 clones near mother plant, 11 at Yerba Buena, ? at triangle10. UC Botanical Garden has 1995 seed set tested at Ransom Seed Laboratory by Dr. Nancy Vivrette. Tetrazolium testing gave 19% viability for individual nutlets for both controlled and open pollinated seeds. Many nutlets had no embryos.16 UC Botanical Garden seed germination experiments result in twelve plants.16 Clone status: 11 clones near mother plant, 8 at Yerba Buena, 1 at triangle10. 30-40% dieback noted.24 Dr. Raabe at UC Berkeley tested samples of the mother plant for plant pathogens and identified Phomopsis spp.9,24 Peter Baye reports clones growing at Regional Parks Botanic Garden3 Tissue culture attempted by Ellen Sutter at UC Davis using the growing tips of the mother plant but too many fungi growing on the plant cells. She tried a similar strategy with a related species but was unsuccessful. UC Botanical Garden has 12 young plants (from the 1995 seed)3,16 Strybing Arboretum has one clone there since before 1984 but it is declining.1,3 Regional Parks Botanic Garden has clones.3 Recovery Plan3 Tussock moth infestation10 Strybing received one clone from Yerba Buena Nursery. All earlier clones had died by 200226 Clone status: 13 are alive3 (7 at Yerba Buena, 1 at the Triangle, ? near the mother Clones stored at Marin Headlands nursery and Fort Funston Nursery.12 These clones are from the East Bay21 but not from UC Botanical Garden16, so they were presumably the surviving individuals of the ~85 cuttings taken to Tilden in 1960, 1981, and 1987. Tilden was “under quarantine” and had to get rid of them.25 40 _____ 2004 2004 2004 2006 2007 2005-2008 9/11/2008 2008 Seed collected from the clones at the Marin Headlands nursery12 ~12 clones still at Fort Funston Nursery.13 Peter Brastow planted all of the clones (~11) that were in any nurseries in the GGNRA at Yerba Buena serpentine.13, 21 These were planted in the late winter and did not get watered. They all died.21 Clones stored at UC Botanical garden had produced seed collected in 1995. 12 plants were grown from this seed but as of 2/2008 only three survive.16 Kirra collected one fruit from a clone at Yerba Buena15 Kirra collected seed from mother plant15 Tom Parker does genetics work on the plants grown from this seed and on seedlings from open pollination at UC Botanical Garden. Preliminary evidence suggests that at least some of these are true to subspecies).17 Raven’s Manzanita workshop at the Presidio’s Golden Gate Club. A report is in preparation. Clone summary. In the Presidio: approximately 9 clones are still found near mother plant, 1 at the triangle, and 7 at Yerba Buena serpentine (Area A). 67 total cuttings ever planted on the Presidio and 17 are still alive. Over 100 cuttings have made their way to various botanical gardens and only 4 are still known. One is at the EBRPD, 2 clones at UC Botanical garden, and one is at Strybing26. Strybing reports that that specimen was gotten in 2002 from Yerba Buena Nursery. Yerba Buena Nursery appears to sell this species but I have found no record of where they got it from. References: 1. 1984 Recovery Plan 2. 1994 VRAP by Sharon Farrell 3. 2003 Recovery Plan 4. 1987 letter to USFWS from NPS 5. Peter Brastow’s VRAP for planting clones on the bluffs 6. Terri Thomas, personal communication 2007 7. Notes page associated with the 1987 letter to FWS. Undated and un-named. 8. 1996 Rare Plant Monitoring Report 9. 1998 Rare Plant Monitoring Report 10. 2000 Rare Plant Monitoring Report 11. 2003 Rare Plant Monitoring Report 12. Presidio Plant Conservation Committee notes 2003 13. Presidio Plant Conservation Committee notes 2004 14. Holly Forbes, personal communication 2003. 15. Kirra Swenerton, personal communication 2007 16. Holly Forbes, personal communication February 2008. 17. Tom Parker, personal communication February 2008. 18. Letter from Peter Straub to the SF Weekly April 2008. 19. Hand written note to Sharon (Farrell) but unsigned (presumably from Peter Straub) dated 5/11/94. 20. Letter from Sue Smith (CNPS, Conservation Chair) to Sharon Farrell dated 4/18/94 21. Peter Brastow, personal communication May 2008. 22. 12/2/86 letter from the Army to USFWS 23. Letter stamped 1/13/88 from Army to USFWS with maps of planted clones and table attached. Another version of the letter was also found and it was dated December 1988 41 24. Arctostaphylos hookeri ssp, ravenii monitoring report – Draft 04/99 25. Email from Sharon Farrell to Katrina Strathmann, Terri Thomas, and Betty Young 2003 26. Email from David Kruse, 10/15/2008 42 APPENDIX 2 – 2008 Monitoring Report GGNRA (Presidio) Special Status Plant Species Monitoring 2008 Arctostaphylos hookeri G. Don ssp. ravenii P. V. Wells (PRESIDIO MANZANITA, RAVEN’S MANZANITA) REPORTER: Michael Chasse, GGNRA, National Park Service LIFE HISTORY: Perennial, woody shrub. Flowering time is between January through April. RARITY STATUS: Federal Endangered; State Endangered; CNPS List 1B.1 (Rare or Endangered in CA; seriously endangered) RANGE: Endemic to San Francisco, California; known from only one extant native occurrence at the Presidio in San Francisco; plants there belong to a single clone; five of six historical occurrences extirpated by urbanization (CNPS 2001). PRESIDIO POPULATIONS: The single “parent plant” and 17 clones exist near the World War II Memorial in the Presidio. MANAGEMENT OBJECTIVE: Maintain presence of Arctostaphylos hookeri ssp. ravenii at all 3 Presidio locations. MONITORING OBJECTIVE: Conduct annual census and assessment of general conditions at all locations. 2008 MONITORING RESULTS: Location Subsite name Monitoring attribute 2008 Results General trend (past 5 years) W.W. II Memorial Raven’s manzanita census Parent plant and approx. 10 clones present Stable W.W. II Memorial Yerba Buena (W. of Lincoln) census approx. 7 clones present Stable W.W. II Memorial The Triangle census 1 clone present Stable Surveys were conducted on January 11, 2008. Monitoring was conducted by staff and interns from the National Park Service and Presidio Trust. Parent plant and clones were 43 surveyed for presence and condition. It is no longer possible to distinguish and count individual clones at the ‘Raven’s” subsite without damaging plants, due to the expansion of growth and co-mingling of branches between plants. As no significant dieback has been observed, i.e., dieback matching the average size of a clone, it can be inferred that clones counted in previous years remain extant. Native plants associated with A. hookeri ssp. ravenii include: Achillea millefolium, Ceanothus thyrsiflorus, Chlorogallum pomeridianum var. divaricatum, Dudleya farinosa, Eriogonum latifolium, Grindelia hirsutula var. maritima, Iris douglasiana, Lupinus variicolor, Oemlaria cerasiformis, Rubus ursinus, Polypodium californicum, and native perennial grasses. Currently, there is no accepted protocol for demographic monitoring of Arctostaphylos hookeri ssp. ravenii. A workshop on management of A. hookeri ssp. ravenii was hosted by the Presidio Trust and National Park Service on September 11, 2008. Results from this workshop may guide future approaches to demographic monitoring of the species. THREATS: Although most herbaceous weeds have been effectively controlled in the areas surrounding A. hookeri ssp. ravenii, Oxalis pes-caprae continues to be abundant just east of the parent plant. Ceanothus thyrsiflorus (coast blue blossom) is encroaching upon many of the clones in the “Raven’s” and “Yerba Buena” subsites, and in many (but not all) cases the shading is causing dieback on clones. Leaf and branch dieback, previously attributed to fungal activity, continues to be observed. New growth appears healthy at branch ends, but dieback areas are not regenerating and remain as gaps in the canopy. Native plants, such as Chlorogallum pomeridianum var. divaricatum, overtop the manzanita canopy during each growing season and also appear to be contributing to leaf dieback. Herbivory, apparently by small mammals, has been observed on manzanita branches and may be another factor in dieback. A large stand of non-native trees, mainly Pinus radiata and Cupressus macrocarpa, remain to the north and west of Arctostaphylos hookeri ssp. ravenii habitat. The effects from these trees on microclimate patterns have not been measured but may be a threat maintaining the environmental conditions necessary for preserving this species. CURRENT MANAGEMENT: On-going manual removal of non-native plants such as Oxalis pes-caprae, Briza maxima, and Plantago lanceolata through the Presidio stewardship program. Occasional small-scale plantings of coastal prairie species in areas where the native plant component has been lost or greatly reduced due to the effects of nonnative trees and invasive plants; no plantings have been conducted within 30 feet of Arctostaphylos hookeri ssp. ravenii individuals. MANAGEMENT RECOMMENDATIONS: 44 Continue on-going stewardship of A. hookeri ssp. ravenii habitat, particularly hand and mechanical weed control and revegetation in areas previously disturbed or occupied by non-native trees. Consider the use of herbicide to control Oxalis pes-caprae and prevent its spread into habitat occupied by the parent plant. Prune back Ceanothus thyrsiflorus where it encroaches upon individuals of Arctostaphylos hookeri ssp. ravenii. Plan for the phased removal of non-native trees to the north and west of A. hookeri ssp. ravenii habitat. CURRENT RESEARCH: Propagation of A. hookeri ssp. ravenii at UC Berkeley Botanical Garden (Holly Forbes) and genetic testing of seedlings (Tom Parker, SFSU) to determine offspring that would be genetically appropriate for outplanting to augment the current single genetic individual in the Presidio. 45 APPENDIX 3 – Workshop on Presidio manzanita conservation and management Arctostaphylos hookeri ssp. ravenii update and planning workshop, 11 September 2008, Presidio of San Francisco. The objective for the September 2008 Presidio Manzanita workshop was to develop guidelines for a 5-year outline of steps towards recovery. The morning session for the workshop were presentations concerning history and status of the current population (Mark Frey, Michael Chasse), propagation and germination trials (John D, Holly Forbes, Kirra S), status of the recovery plan (Valary Bloom), status of A. franciscana and potential for recovery (Michael Chasse) and ecology of the Presidio manzanita and genetic status of seedlings from UC Botanic Garden (Tom Parker). In the afternoon were a series of break out sessions in which particular questions were considered by small groups of individuals. 8:00 8:30 9:10 9:30 9:55 10:10 10:30 11:00 11:30 Terri, Betty, Sue Welcome / introductions / objectives Michael C and Mark Review and amend management history. What is a meaningful monitoring regime? John D. / Holly F. Propagation and seed germination at UC Bot. Garden Kirra S Update on germination trials at the Presidio Tom P. Arctostaphylos ecology BREAK Valary Bloom Recovery plan overview and history Michael C A. franciscana update Tom P. Arctostaphylos taxonomy update Tom P. Arctostaphylos hookeri ssp. ravenii genetics Mark Frey Identify groups for breakout sessions. 11:45 LUNCH 12:45 Break out session 1 1. (Lew) What questions remain to guide our choices? 2. (Mark) What is the role of fire for this species? 3. (Kirra) What are the issues and solutions for propagation in nursery and field 4. (Michael) Is there a seed bank? Should we go looking? How? 1:15 Mark Frey Group reports discussion 2:15 BREAK 2:30 Break out session 2 5. (Kirra) Where do we plant the next set of plants? 6. (Michael) Is A. franciscana appropriate for reintroduction? 7. (Mark) How should we monitor the mother plant/existing clones/new plants? 8. (Lew) What are the parameters/problems/solutions we should consider when discussing the genetics of outcrossing? 3:00 Mark Frey Group reports and full group discussion 46 4:00 Terri T. Review Outcomes 4:30 Sue, Terri, Betty Thank you List of those Invited and Attendees attend Sept 11 mtg No Last Name Albert First Name Marc Organization Title National Park Service Natural Resource Management Specialist Coastal Plant Ecologist Fish and Wildlife Biologist No Yes No Yes Yes Baye Bloom Brastow Chasse Cooley Peter Valary Peter Michael Gene No No Delgado Domzalski Bruce John No Yes No Edwards Ehrlich Elam Steve Peter Diane Yes Evans Richard No Yes Farrell Forbes Sharon Holly Yes Yes Yes Frey Fritzke Hackett Mark Sue Wes No No No Hayes Hildebidle Keeley Grey Brian Jon No Yes No Yes Lambert Markos McKechnie Parker Amy Staci Michael Tom No No No No No No Yes Poinsot Raiche Raabe Raven Rogers Straub Stringer Wendy Roger Robert Peter Debra Pete Lew San Francisco State University GGNRA Planet Horticulture UC Berkeley Missouri Botanical Garden UC Davis U.S. Army National Park Service Yes No Swenerton Thomas Kirra Terri Parks Conservancy The Presidio Trust US Fish and Wildlife Service Nature in The City National Park Service California Department of Fish and Game University of California Botanical Garden Tilden Botanic Garden The Presidio Trust US Fish and Wildlife Service Stewardship Coordinator Botanist, Bay Delta Region North Propagator Forester Deputy Chief, Division of Listing, Recovery and Section 10 UC Davis Professor, Department of Plant Science Golden Gate National Parks Conservancy University of California Curator Botanical Garden The Presidio Trust Supervisory Ecologist National Park Service Supervisory Vegetation Ecologist UC Davis Adjunct Professor, Department of Plant Science Elkhorn Slough Coastal Training Program The Presidio Trust Stewardship Coordinator USGS Western Ecological Research Scientist Research Center University of California Jepson Herbarium 47 Environmental Planner, Fire Program President Natural Resources Mangament Specialist Propagule Collector Director of Cultural and Natural Resources No No Yes Yes Vasey Ward Warne Young Mike Kristen Betty Betty No-unable to contact No-unable to contact Yes McMillanBrowse White Philip Hull Josh Wayne National Park Service US Fish and Wildlife Service Golden Gate National Parks Conservancy Wisley Bot Garden? Director of Nurseries U.S. Fish and Wildlife Service U.S. Fish and Wildlife Service 11 September 2008 Presidio Manzanita Workshop; Break-out Session Notes FIRE Break-Out Session Notes 1. Presidio Fire History see FMP little available old oaks in GGP could tell a fire history if cored San Francisco—1840s, 1906 “No” lightning strikes Native American burning—assumed here 2. Other disturbances that might play a role Landslides, ungulate, bears, flooding If fire interval is very long, then there would be a 200year generation time, therefore, there are few generations in 10,000 years 3. Ways to use fire FMP for NPS permits PT work with NPS 4. Things to try Burn box on entire clone Has it been long enough for the seedboat to develop and be buried? (probably only 4 years) Kill adult Make sure it has been seeding One clone every ten years? Liquid smoke/ash/smoke typically soak seeds for 24 hours In field In greenhouse? The liquid in the field may be a problem Treatments on related Mt. Tam? (1920—last fire); Treatments at Mt. Davidson? 48 Burn box downhill of existing clone burn first then plant—kill fungi Eventually try at the mother plant 5. Maintaining adults? Unlikely because is doesn’t re-sprout MONITORING Break-Out Session Notes Lots of things listed in Recovery Plan but they are vague “Site-wide” Pollinators Do a pollinator study for the species Seeds Growth Seed production What we do Survivorship Possibilities Transects (a) Bury tubes that are paired (b) Note length of plant at each transect Photos (a) Kites—beware of traffic (b) Poles—or use painting extenders (c) Ladders—not practical (d) Frame (i) Use fisheye? (ii) Have fixed corners to reuse (iii)Use bright stuff to help ID exact locations in photos Do we need to monitor size? Maybe not Can we just monitor threats with a qualitative assessment and photomonitoring? Do a simple/repeatable photo technique Clones: can’t tell apart; focus on cover SEED BANK 49 Break-Out Session Notes Is there a Seed Bank? Yes Needs to be re-proposed in situ release rather than dig Question: What is the plan if/once found? Actions: Looking at myco tips? See below 5 cm Where should we go looking? Check historic locations where serpentine (or greenstone) is still uncovered Manzanita guy Knows Laurel Hill outcrop location? In Situ—needs a plan/needs attention Pump, sprayer, option Supplement watering Rodent proofing Have cages ready Damage to root system Not a big issue What distance? Not worth going below 5 cm. Flaming? Smoke? It is in the smoke Sterling Keeley Do A. montana stand first Arctostaphylos franciscana + Raven’s Manzanita Break-Out Session Notes Is co-reintroduction an important objective? Sympatric and important Could hybridize… into tetraploid Do it away from original “population” There are precedents, ie., Condor Easy because not listed How many genetic individual are there in cultivation? Steve Edwards ? at Yerba Buena 50 Don Mahoney ? at Las Pilatas Other items The flowering times may not overlap They may support more pollinators when together SFNAP call for A. franciscana re-introduction Bernal Heights PROPAGATION Break-Out Session Notes Question: What are the issues and solutions for propagation in the nursery and field? Goal: Establish several breeding populations. Objective: Perfect propagation techniques including: germinating seed, rooting clones, growing on, field establishment Actions: Salvage maximum amount of seed as possible from clones every year to increase material available for experimentation. Review and consolidate existing seed/clonal propagation data, document best practices. Send in 400+ seed to Ransome Seed lab for viability testing Try floating/sinking seed as a first pass at judging viability X-ray current seed inventory to assess seed viability (non-destructive method) Davis nursery or CDFA (state ag) or seed certification program may have one. Root cuttings from clones, grow to maturity and do pollinator exclusion/ hand pollination to produce known self-pollinated seed Take cuttings (Nove-Jan) and increase number of clones of seed plants (from UC Berekely) for outplanting experiments Future Research: What liquid smoke product to use? Quantify active compounds in smoke. Determine appropriate concentration of smoke product. Determine seed viability of self pollinated seed. Pollination biology questions, what pollinates this plant? What is the range of these pollinators? Are there other Arctostaphylos that could potentially hybridize with the Raven’s within the range of its pollinators? Survey nearby neighborhoods. 51 Try additional germination treatments including: GA 47 and BA combo, varying smoke concentrations, burial of seed and burning of excelsior, varying strat period, sulfuric acid, hot water or mechanical scarification and combination of treatments, Propagation treatments: mycorrhizal fungi addition aid in germination/rooting How to retain clones in containers and manage for maximum seed production? Revisit micropropagation possibilities – Valerie Pence at CREW (Cincinnati Zoo) Know info: Parent plant and some clones produce seed. Plants are very sensitive to overwatering in nursery Plants don’t do well in containers for very long Seed from UC Bot Garden (some selfed/some outcrossed seed) showed 19% viability with tetrazolium testing (higher for multi-nutlet stones, lower for single nutlets) Previous micropropagation attempts had pathogen problems (Fusarium sp.) WHERE SHOULD WE PLANT? Break-Out Session Notes Question: Where do we plant the next set of plants? Goal: Establish 2+ new populations within the Presidio and 5+ outside the Presidio Objectives: Find most suitable sites Determine proper site preparation, planting and aftercare techniques Types of plants: Clones of parent, A. franciscana, seed-grown plants (or clones of these) resulting from self pollination of original clones Sites: Refer to Recovery Plan and Michael Chasse’s site evaluation for A. franciscana: Franciscan manzanita M. Chasse.ppt Within the Presidio: Coastal Bluffs, Inspiration Point, Quarry Area (Hesperolinon congestum site), Log Cabin, West Crissy Bluffs, Golf Course Site conditions: serpentine soils or very poor soils, outcrops or more developed soils, sunny, mix up slope and aspect to assess optimum conditions Consider greenstone locations. Should chert, bare colma or other poor soils be included? Investigate outside Presidio locations Prioritize first experimental plantings in areas outlined in Recovery Plan 52 Future Research: Why did some past plantings fail? How were those failed plantings sites managed? Planting timing of failed attempts may have been too late in the year (March) and then may have been over watered through the dry season What are the minimum numbers to plant to start new populations? Planting density? Assess site prep techniques including: pre-burning to kill fungal pathogens, scrape and burn, scrape and apply smoke water Will pre-burning planting site actually be hot enough to kill pathogenic fungi? Try putting thick layer of straw or burn pile on top of site to increase temperature of burn Try inoculating rooted cuttings in containers with mycorrhizal fungi to assess, try amending planting holes Which fungi to use? When does inoculation need to occur? Where to obtain inoculum? Possible sources: around parent plant (doesn’t exclude pathogenic fungi), from other around other woody plants/pines in area, from mycorrhizal mushrooms collected around conifers in area (create slurry and pour around planting site), from other manzanita sites with closely related species (may be cleaner material, outside park reintroduction issues?) Should plants be watered for first year after installation? What is the optimal size container for plants? In 1987 were probably 4” pots. Best to keep containers small because of rocky soils and fact that plants don’t do well in containers in nursery Could there be Sudden Oak Death issues with container soil? Conduct seedbank analyses before outplanting any plants (A. montana ssp. ravenii or A. franciscana or other potentially hybridizing plants) so as not to confound seedbank study results Actions Experimental planting of clones from selfed seedlings grown at UC Berkeley should be planted away from original parent plant. How far away? Experimental planting should seed to restore evolutionary processes and include clones of original parent plant, clones of selfed seedlings and clones Check with SF Mycological Society for inoculum, or JR Blair from SF State who specializes in mushroom associations with manzanitas (Tom Parker has his contact info) New populations should be of varying age classes – stager planting timing to plan for this Associated planting should include pollinator attractors ex: Ceanothus and Eriogonum Future plantings should be planted in grids with centers marked/GPS’d to aid in future monitoring efforts. Should they be planted further apart? OUTCROSSING Break-Out Session Notes Question: 53 What are the parameters/problems/solutions we should consider when discussing the genetics of outcrossing? Goal: Re-establish evolutionary processes Objectives: Establish a reproducing population with the highest potential for genetic variability. Future Research: Does existence of selfed seedlings change our strategy change the need for introgressive breeding? What is the genetic diversity of selfed seedlings? Does selfing affect seed viability? Are we selecting for certain phenotypes? Does seed collected from the parent plant and existing clones in the Presidio need genetics work? How far does pollen move? Where is the closest congener in the neighborhood? If introgressive breeding program is to be pursued, which species should it be crossed with? A. franciscana or A. montana ssp. montana? Should A. montana ssp. montana be planted with A. montana ssp. ravenii? Both are tetraploids but there may be phenological reproductive barriers (differences in bloom time). Risk of uncontrolled introgression if they cross pollinate in the field. Actions: This winter, take cuttings from selfed seedlings grown at UC Berkeley and increase numbers of clones of each of these, resulting plants can be ready in about one year Equalize the genetic input into each new site/plant equal numbers of each type of plants (clones from mother, clones of each selfed seedling) Survey neighborhoods adjacent to Presidio (Sea Cliff, Richmond District) for other manzanita species USFWS will tackle question of continuing introgressive breeding alternative, accounting for new information on selfing potential A. franciscana should be planted with A.montana ssp. ravenii because they historically occurred together Known info: All these coastal Arctostaphylos species seem to begun with small endemic populations in the first place Several seedlings resulting from seed collected from clones at the UCB Botanical Garden appear to be products of selfing based on three nuclear genes (one is now dead): 2000.191, 2000.195, 2000.196 and “unlabeled”. 54 A.franciscana, A. montana and A. m. ravenii are all within the same clade but Mt. Tam and Presidio manzanita are both tetraploids, while the Franciscan manzanita is diploid. Reference Tom Parker’s presentation: ArctoEvolSept08 T. Parker.ppt Reference symposia documents from Center For Plant Conservation on this subject of small populations genetics RESEARCH QUESTIONS This is a compilation of questions identified during the day, most are also listed within the notes for the breakout session. Pollinators Which species do we have? Which species do we need? What plants can support those species? Seed Bank Fire History in Presidio Seed predations X-ray seed viability Should we collect 100% of seed? Burn Boxes Burn box on entire clone Liquid smoke/ash/smoke Treatments on related Mt. Tam? (1920—last fire); Treatments at Mt. Davidson? Burn box downhill of existing clone Eventually try at the mother plant Propagation: What liquid smoke product to use? Quantify active compounds in smoke. Determine appropriate concentration of smoke product. Determine seed viability of self pollinated seed. Pollination biology questions, what pollinates this plant? What is the range of these pollinators? Are there other Arctostaphylos that could potentially hybridize with the Raven’s within the range of its pollinators? Survey nearby neighborhoods. Try additional germination treatments including: GA 47 and BA combo, varying smoke concentrations, burial of seed and burning of excelsior, varying strat period, sulfuric acid, hot water or mechanical scarification and combination of treatments, 55 Propagation treatments: mycorrhizal fungi addition aid in germination/rooting How to retain clones in containers and manage for maximum seed production? Revisit micropropagation possibilities – Valerie Pence at CREW (Cincinnati Zoo) Planting: Why did some past plantings fail? How were those failed plantings sites managed? Planting timing of failed attempts may have been too late in the year (March) and then may have been over watered through the dry season What are the minimum numbers to plant to start new populations? Planting density? Asses site prep techniques including: pre-burning to kill fungal pathogens, scrape and burn, scrape and apply smoke water Will pre-burning planting site actually be hot enough to kill pathogenic fungi? Try putting thick layer of straw or burn pile on top of site to increase temperature of burn Try inoculating rooted cuttings in containers with mycorrhizal fungi to assess, try amending planting holes Which fungi to use? When does inoculation need to occur? Where to obtain inoculum? Outcrossing: Does existence of selfed seedlings change our strategy change the need for introgressive breeding? What is the genetic diversity of selfed seedlings? Does selfing affect seed viability? Are we selecting for certain phenotypes? Does seed collected from the parent plant and existing clones in the Presidio need genetics work? How far does pollen move? Where is the closest congener in the neighborhood? If introgressive breeding program is to be pursued, which species should it be crossed with? A. franciscana or A. montana ssp. montana? Should A. montana ssp. montana be planted with A. montana ssp. ravenii? Both are tetraploids but there may be phenological reproductive barriers (differences in bloom time). Risk of uncontrolled introgression if they cross pollinate in the field. 56 Appendix 4. Indication that Arctostaphylos montana subsp. ravenii is of allopolyploid origin. DNA extractions were made from dried material of the Presidio Manzanita provided by the UCBG. This material was used to amplify and sequence alleles from several genes (LEAFY, WAXY, RPB2). These sequences were aligned and used to develop phylogenetic trees, incorporating sequences from a number of additional species. Results from two of the trees appear below in Figure App. 5-1, and App. 5-2. Figure App.5-1. Phylogenetic tree of sequenes from the nuclear gene WAXY indicating multiple alleles from Arctostaphylos montana, but with A. montana subsp. ravenii, all individuals cluster with A. hookeri. The Presidio manzanita clusters with only a single maritime species. 57 Figure App.5-2. Phylogenetic tree of sequenes from the nuclear gene RPB2 indicating multiple alleles from both Arctostaphylos montana and A. montana subsp. ravenii. The Presidio manzanita clusters with a group of maritime species. In these trees, when individual alleles cluster with those of another species, two interpretations can be made. One is that they share an ancient allele that has not changed during the evolution of the group, a second is that the species are close relatives. When a tetraploid species is involved and allopolyploidy is suspected, then the clustering of alleles provides suggestions as to potential parents. Summarizing from three different nuclear genes (LEAFY, WAXY, RPB2), it appears that the Presidio manzanita shares alleles from multiple parents, suggesting an allopolyploid origin. Those parents include A. franciscana, A. hookeri, and multiple potential parents arising from a rapidly evolving group of maritime species to the south of San Francisco. In addition, the Presidio manzanita appears to overlap considerably with that of the Mt. Tamalpais manzanita (a manzanita it resembles) with respect to potential parentage (Figure App.5-3). The overlap suggests the reason why they are similar in appearance. The fact that the Presidio manzanita also contains alleles from A. hookeri that the Mt. Tamalpais manzanita lacks, suggests why they differ in fruit size, the most significant difference between them. 58 Figure App.5-3. This figure shows the potential parentages of both the Presidio manzanita (A. montana subsp. ravenii) and the Mt. Tamalpais manzanita (A. montana subsp. montana). 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