| BEN |
| BOTANICAL ELECTRONIC NEWS |
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| ISSN 1188-603X |
| No. 511 November 15, 2016 | aceska@telus.net | Victoria, B.C. |
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Registration is now open for the First Washington Botanical Symposium. Please visit the following URL for a complete list of speakers, topics, and registration information:
https://botanicgardens.uw.edu/education/adults/conferences-symposia/wa-botanical-symposium/
The symposium is co-sponsored by the UW Herbarium at the Burke Museum, University of Washington Botanic Gardens and the Rare Plant Care and Conservation Program (Rare Care), Washington Natural Heritage Program, and Washington Noxious Weed Control Board.
To plant enthusiasts and nature lovers who have frequented the prairies of western Washington and Oregon over the last two decades, golden paintbrush (Castilleja levisecta Greenm.) is a species whose status has undergone a dramatic transformation. In the mid-1990s when it first became the focus for intensive study and conservation efforts, it was extremely rare across the region. It had been extirpated entirely from Oregon and persisted in less than a dozen sites in Washington and British Columbia, with a total global population probably numbering around 15,000-20,000 plants.
Despite intensive searching throughout the species' historical range in Oregon and Washington, only a couple of small new populations were found, and detailed monitoring of the known populations revealed a precarious picture. Most consisted of only a few hundred individuals or less, several appeared to be in precipitous decline, and a couple winked out entirely before they could be conserved.
Yet today, the species is widespread and abundant, existing in over 40 sites across its entire historical range and now numbering around a quarter of a million individuals. The remarkable turnaround in the status of this species not only makes C. levisecta a poster child for successful conservation efforts in the Pacific Northwest but also provides important lessons for how efforts to conserve a single species can be carried out in ways that galvanize conservation of an entire ecosystem.
Castilleja levisecta was federally listed as a threatened species in 1997 after various surveys and studies highlighted its extremely rare status and a need for aggressive, proactive conservation to ensure its long-term survival and reverse the long-term decline of the species. This listing under the US Endangered Species Act was critical for several reasons.
First it stimulated the US Fish and Wildlife Service (USFWS) to provide consistent, substantial funding over many years to acquire and protect key sites and initiate a diversity of research efforts necessary to begin to understand the biology, genetics, reproduction, and ecology of the species. Often supported by USFWS funds, many graduate students directed their studies toward numerous aspects of C. levisecta natural history, providing a wealth of knowledge and growing expertise that has stimulated and sustained its conservation. This increased funding was essential for developing and maintaining ongoing management of many sites to enhance their suitability for sustaining viable paintbrush populations.
The USFWS funding supported much of the production of seedlings for outplanting and the development of nurseries to specifically produce large quantities of pure Castilleja levisecta seed for restoration efforts, as well as the studies to evaluate the suitability of potential recovery sites.
Finally, the USFWS played a key role in facilitating collaboration and cooperation among many partners in Washington and Oregon, elements that were essential for paintbrush recovery across its entire historical range. The USFWS supported numerous meetings and field trips that were a key aspect in exchanging information, experience, and lessons learned, as well as helping to develop the relationships among individuals and organizations that allowed for the sharing of seed, materials, equipment, and other resources.
>From the outset, Castilleja levisecta recovery has focused on three main elements.
Because there were so few extant sites left to serve as a guide, the last element has proven challenging. Early efforts focused on identifying new sites that matched the physical environment and vegetative composition of the sites where wild populations remained. However, our subsequent experience revealed that these new sites may not be representative of the sites where C. levisecta historically thrived best. We have hypothesized that optimal sites may have been relatively productive, deep-soil prairies, most of which were converted to agriculture long ago. The species has persisted today in a few relatively marginal, remnant sites that were unsuitable for agriculture.
One key thread consistent with all these recovery efforts has been an emphasis on restoring the overall health and integrity of potential recovery sites. This has included enhancing their biodiversity by planting diverse native prairie species, controlling invasive noxious weeds, and restoring or maintaining key ecological processes like fire and pollinators. These actions sometimes were supplemental to fostering key elements that enhanced their suitability for Castilleja levisecta, such as establishing host plants for the hemi-parasitic paintbrush and ensuring that fire or other disturbance that helped enhance paintbrush reproduction occurred as appropriate. But this approach resulted in overall improvements in the viability and resilience of the native prairies, regardless of the ultimate success (or not) of the C. levisecta recovery efforts at a particular site.
Although the main elements of Castilleja levisecta recovery have remained largely constant, there have been significant changes over time to the strategies and actions we have employed as experience demonstrated which approaches were most successful. For example, initial efforts to establish or augment populations focused particularly on outplanting nursery grown plugs. Although this practice continues in some areas, it is a costly, time-consuming, and labor-intensive process. Therefore at many sites we are increasingly focusing on sowing Castilleja levisecta seed (along with seed from other native prairie plants) in sites that have been carefully prepared to enhance seed germination and survival. This strategy has become possible only since about 2011, when nursery-grown seed became available in sufficiently large quantities. As a result, populations of 10,000 to more than 100,000 plants have been established relatively quickly in several particularly suitable sites. These large populations create an added benefit because they produce enough seed to sustain themselves and also have provided seed for restoration at other sites.
Identifying the elements that are most critical to render a site suitable for supporting a viable Castilleja levisecta population sometimes is relatively straightforward. It may be obvious that encroaching shrubs or trees need to be controlled. Grazing by deer, rabbits, or voles on flowering stems may be quite evident, and limiting their impacts may be imperative. Native species that can serve as host plants may be conspicuously lacking and may need to be planted to increase their abundance. Invasive weeds may be extensive and must be controlled to reduce competition with C. levisecta. At other sites, however, key threats may be more difficult to discern. Similarly, devising ways to abate these threats or otherwise enhance site suitability may present challenges of variable difficulty. Trees can be cut, shrubs can be mowed, but excluding deer or voles, conducting burns on a regular basis, or establishing diverse native host plants often can be difficult. Ongoing research is essential to devise and refine management strategies that efficiently and effectively address these myriad restoration challenges.
The road to Castilleja levisecta recovery has not been linearly upward. The droughts of 2014 and 2015 may have cumulatively resulted in significant drops in many C. levisecta populations and has forced us to consider more carefully which sites may be most suitable for this species in light of future climate changes. It is noteworthy that despite intensive efforts at most of the extant natural populations, many have not increased greatly in size. Instead most of the increase in overall C. levisecta abundance is largely accounted for by the establishment of new populations.
Recent work has demonstrated that Castilleja levisecta can serve as a primary food plant for larvae of the endangered Taylor's checkerspot (Euphydryas editha taylori), a butterfly that once thrived and shared many lowland Puget Sound prairies with C. levisecta. This connection affords an unusual opportunity for building on the gains made recovering one rare species to simultaneously enhance the recovery of another. But the potential synergies this situation offers are not as simple as "plant more golden paintbrush, support bigger populations of Taylor's checkerspots." In most sites where checkerspot recovery is underway, Castilleja levisecta has been absent, and the butterflies are feeding on harsh paintbrush (Castilleja hispida) or lance-leaf plantain (Plantago lanceolata). Both species present challenges to C. levisecta recovery. The two paintbrush species have been shown to hybridize readily with each other, thereby jeopardizing the genetic integrity and long-term recovery of C. levisecta populations growing in the same site. The plantain is a non-native species that can be quite aggressive in some sites and may compete with paintbrush and other native prairie species.
Despite such concerns the future is bright for the continued spread of C. levisecta across the prairies, coastal bluffs, and rocky balds of the Puget Lowlands. Furthermore, as paintbrush populations once again become re-established, ongoing conservation management of these sites will also bring with it the restoration and enhancement of their overall biodiversity, resulting in a cascade of benefits to the prairie ecosystems in the Pacific Northwest.
The set up of the book is traditional, with a significant introductory part, reviewing what is a Hebeloma and the history of the genus. Characteristic microscopic features are discussed and illustrated in detail, since in this genus they form such an integral part of correct identification. Results of molecular studies, as they bear on the genus and its classification, are outlined with several beautiful trees. The sections and subsections of the genus are explained and keys are provided for each. Then follows the floristic part, with thorough macro- and microscopic descriptions of all known European species, arranged by section and subsection. Each species has a reproduction of the original diagnosis or protologue (English translation, where required) , a description of any neo- or lectotype. This alone is an incredible resource for anybody who has ever spent time chasing up old protologues and type specimens. Descriptions, based on several specimens and collections, include habitat and distribution, with figures showing distribution and phenology. Next comes a very helpful section discussing ecological and habitat keys: which species you might find in any specific environment. This is followed by an annotated list of Eurafrican names, before closing with the bibliography. The remaining book, just less than half, is made up by iconography: the colour pictures. While it is unfortunate that these did not come together with their respective text, putting all colour printing together significantly lowers printing costs, making the ridiculously low price possible.
So far, a rather conventional set-up, you may think. What makes this book so special? Two factors, above all: 1) the exactitude, thoroughness and completeness of the work, and 2) it is solely based on a huge database accumulated by personal observation. Taking advantage of computing capabilities, a routine way of documenting information has made it searchable, so that any character may be investigated or quantified. This book brings together virtually all that is known about the genus in Europe, but not as the result of an attempt to collect and reproduce such knowledge from old tomes. Rather, it is the product of the authors' personal knowledge and experience with the genus after many years of dedicated study, beginning in the field and taken into the laboratory: in the course of this study, past knowledge has been accumulated and tested against repeated direct observation. This is a travelogue by guides who have been there, lived and breathed Hebeloma in all its settings.
The database on which descriptions and ranking are based numbers some 4,500 Hebeloma collections, all personally studied by the authors. Descriptions bring out both the typical morphology, as well as all variations. Only in a very few uncommon species with few collections, would the full morphological spectrum not be covered. Iconography follows a similar approach. Macroscopic illustrations are generous: one-half page in size; the majority are illustrated by at least four photos, some several times that number. Photomicrographs are arranged eight to a page, with four or more pages not being unusual.
The third author of the book is Jan Vesterholt, a noted student of the genus. His initial work laid the foundation, and the book is dedicated to him posthumously, with the cover illustration showing Hebeloma vesterholtii, so named to honour this colleague.
For the last two decades Ursula Eberhardt, Jan Vesterholt and I have been studying the genus Hebeloma. Our European monograph was published earlier this year. See Andrus Voikt's minireview above.
We have already begun to extend this work to the rest of the world. The next major area we wish to address is North America. As well as understanding the North American taxonomy we also hope to address the species overlap between North America and Europe. In order to make this study meaningful we need collections from throughout North America, where we anticipate discovering some new species. Ideally we need good collections, carefully dried and with good pictures; also good macroscopic descriptions particularly of any characters that may disappear with drying such as odor. We can attend to the microscopic descriptions. We have developed a recording sheet for the macroscopic description (See p. 3). We are thankful to all who have already submitted collections but need help to assemble a more representative sample, across the whole continent. This will be Citizen Science at its best. Our goal is a future monograph on the Hebeloma of North America, although this is probably several years away. However, we will of course send information regarding our determinations to contributors of material, and all such contributions will be fully acknowledged. In due course we will establish a website so that all contributors will be able to see their collections on a map of North America.
This genus has long been regarded as difficult and consequently Hebeloma are rarely recorded. Within Europe there are some 300 published names and in North America there are over 200 additional published names. In Europe the list of published names boiled down to 54 species, and, during the course of our studies, 30 species new to science were discovered. In order to unravel the taxonomy and phylogeny of this difficult group, we developed a methodology combining molecular analysis with the functionality provided by a powerful database, allowing the comparison of hundreds of morphological characters (macroscopic and microscopic) and molecular characters from several loci.
Our database has details of more than 5000 collections, of which over 4000 are European and already almost 700 are from North America. The database also contains details of all the European holotypes, isotypes, lectotypes, epitypes and neotypes that we have been able to locate. We have also now started work on the North American types. Our monograph, which was published earlier this year, describes in detail the 84 species of Hebeloma that we currently recognise within Europe, provides keys based on morphological characters and also extensive molecular data as well as more than 500 pages of colour photographs. It also includes a commentary on all the existing European names, on their synonymies and their various interpretations. We are sure that there are still more new species to be described from Europe (as well as new species from North America) and we hope that our monograph will act as a catalyst to enable this discovery. Joel Horman of the Long Island Mycological Club has kindly agreed to act as receiver for North American collections which he will then package together to send on to us.
We have set up a FedEx system so that the sender should incur no cost and as little inconvenience as we can manage. Just contact Joel at jlhorman@optonline.net and he will provide delivery instructions. Please include a copy of the filled out form with your specimens. We appreciate any help we can get with this project. Henry Beker henry@hjbeker.com & Ursula Eberhardt ursula.eberhardt@smns-bw.de
[BEN Editorial Note: For the collecting form see page 3 of http://www.namyco.org/docs/MycophileSeptOct2016.pdf Form archived at http://bomi.ou.edu/ben/511/mycophile-collecting-form.pdf
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