ABSTRACTS

Introduction to Mead’s milkweed Notwithstanding these discoveries, the ( meadii Torr.) and its habitat species faces serious threats. Roughly 60% of populations for which counts are available Craig C. Freeman, R. L. McGregor never have been observed with more than 25 Herbarium & Biological Survey, ramets. Habitat destruction and alteration 2045 Constant Avenue, Lawrence, KS from residential and urban development, and 66047-3269, [email protected] from agricultural changes, continue to impact populations. Annual haying, a common land Mead’s milkweed (Asclepias meadii Torr.) is use on prairies in Kansas and , a long-lived, perennial herb endemic to the prevents full development of fruits and is central United States. are self- implicated in reduced genetic diversity incompatible, pollinated by small bees, and within populations on hay meadows. Sericea can spread by . Seed dispersal is by lespedeza [Lespedeza cuneata (Dum. Cours.) wind. Populations occur on dry-mesic to G. Don] may pose a new threat to some mesic, glaciated or unglaciated tallgrass populations. prairies or glades. Substrates are sedimentary (limestone or sandstone) or, Mead’s Milkweed Recovery Plan rarely, igneous. Described 150 years ago, few extant populations were known until the Kristopher Lah, Endangered Species 1980s. When listed as threatened in 1988, Coordinator, U.S. Fish and Wildlife Service, Mead’s milkweed was known from 81 extant Chicago Field Office, 1250 S. Grove, Suite populations. Today, 225 extant populations 103, Barrington, IL 60010, are known in 34 counties in , , [email protected] Kansas, and Missouri. Distribution of these populations is highly skewed toward the The Mead’s Milkweed (Aesclepias meadii) southwest edge of the historic range. Nearly Recovery Plan was completed in 2003. Like 91% of extant populations are in 23 counties most federal recovery plans it consists of in eastern Kansas and west-central Missouri, three chapters, introduction; recovery; and largely in the southern Central Irregular implementation. This presentation will Plains ecoregion. Another 4% of extant briefly cover chapter one, introduction, of the populations are in eight counties in southwest plan which provides a description of the Iowa and north-central Missouri, in the species, its status, habitat, and biology. This northern half of the Central Irregular Plains. presentation will focus mainly on the Remaining extant populations are in the recovery plan’s chapters that mesh with the Ozark Highlands of southeast Missouri and theme of the symposium, recovery and Interior River Lowlands of extreme southern implementation. Chapter two of the plan Illinois. Populations from the Central Corn identifies the recovery objective to delist the Belt Plains (northern Illinois, northwest species with populations representative of the ), Driftless Area (southwest range of the species’ habitats and geographic ), and Western Corn Belt Plains distribution. A brief description will be (east-central Iowa) are historic. Surveys for discussed of the plan’s framework to meet new populations continue to be fruitful; the recovery criteria with a minimum number systematic inventories in Kansas in 2004 and of viable populations across Mead’s 2005 yielded 39 new populations. milkweed’s range. Chapter two continues with a description of the actions that will be estimation of population size and patch accomplished in order to reach the recovery survival using mark-recapture methodologies criteria. Chapter three of the plan more typically used in animal studies. Our summarizes the actions that need to be study has revealed that population size at the implemented to recover the species in a site is likely to exceed 125 patches despite schedule that provides an approximation of the fact that many years have many fewer the cost and timeframe that actions may be patches. Yearly patch survival is high accomplished. Hardcopies of the plan will (geometric mean = 0.96), and can only be be available for attendees and can be accurately assessed with long term data sets. downloaded at: Recruitment, as measured by the appearance http://www.fws.gov/midwest/Endangered/pla of new patches, occurs frequently enough to nts/meads-fnl-rp.pdf. balance the 4% mortality, suggesting that population numbers are being maintained Research on Mead’s milkweed at the over time. Fruit production at the site is Rockefeller Prairie in eastern Kansas: A variable, but never exceeds 45 pods across 19-year perspective the site in a single year, and often is much smaller. The best predictor of fruit number is Helen Alexander, Department of Ecology the number of flowering stems, which in turn and Evolutionary Biology, University of is often higher in years with dormant season Kansas, Lawrence, KS, 66045, burning. The variability observed in both [email protected] fruit number and number of new patches Dean Kettle, Kansas Biological Survey, suggest that recruitment may be often 2101 Constant Avenue, Lawrence, KS, episodic in nature. 66047, [email protected] Norman Slade, Department of Ecology and Factors limiting Mead’s milkweed fruit Evolutionary Biology, University of Kansas, production in eastern Kansas Lawrence, KS, 66045, [email protected] Galen Pittman, Kansas Biological Survey, Emily Grman, W.K. Kellogg Biological 2101 Constant Avenue, Lawrence, KS, Station, 3700 E. Gull Lake Dr., Hickory 66047, [email protected] Corners, MI, 49060, and Department of Biology, Michigan State University, East Nineteen years of observation, using a Lansing, MI, 48824, [email protected] standard monitoring protocol, has provided Helen Alexander, Department of Ecology new insights into the population biology of and Evolutionary Biology, University of Mead’s milkweed in a 4 ½ hectare prairie Kansas, Lawrence, KS, 66045, remnant in northeastern Kansas. Our initial [email protected] question (is the population increasing, decreasing, or staying constant in numbers Most remaining populations of Mead's over time?) has proved to be challenging milkweed produce very few fruit, threatening since milkweed patches (i.e. spatially their long-term viability. In Rockefeller aggregated groups of stems, which Prairie in 2002, we conducted an approximate genetic individuals) are difficult observational study to test hypotheses of to detect in the dense prairie, and individual factors limiting fruit production. We found plants can survive, but have no above ground that lower rates of pollinator visitation were parts in some years. We have thus combined not associated with lower fruit production, our analyses of observed patches with suggesting that pollen limitation was not

2 important in this population. Larger plants From 2001 until 2006 no prescribed burns tended to produce more fruit, indicating that were conducted at either site. General trends resource limitation may have lowered fruit observed over the monitoring period at the production. However, impacts of both pollen Weimer Hill site were an increase in the and resource limitation were outweighed by number of plants with multiple stems, an vertebrate herbivory, which caused a 63% increase in the number of stems inventoried, reduction in the number of plants capable of a decrease in the number of flowering stems, producing fruit. Understanding the factors a decrease in the average height of the stems, limiting fruit production in a natural and a decrease in the average width of the population can help us increase fruit widest leaf. The Mina Sauk Falls population production and population growth in natural exhibited an increase in the number of stems and managed populations of Mead's inventoried, and an increase in the number of milkweed. flowering stems over the same time period.

Mead’s milkweed monitoring at Taum 1- "Genetic Variability in the Federal Threatened Mead's Milkweed, Asclepias meadii Torrey (Asclepiadaceae), as Sauk Mountain State Park, Missouri Determined by Allozyme Electrophoresis." Diane L. Tecic, Jenny L. McBride, Marlin L. Bowles, Daniel L. Michael P. Currier, Missouri Department of NickrentAnnals of the Missouri Botanical Garden, Vol. 85, No. 1 (1998), pp. 97-109. Natural Resources, P.O. Box 176, Jefferson City, MO, 65102, [email protected] Population status, propagation, and Dan Drees, Missouri Department of management for Asclepias meadii (Mead’s Conservation, P.O. Box 180, 2901 W. milkweed) in Missouri Truman Blvd., Jefferson City, MO 65109. Emily S. Horner, Missouri Department of In 1991, after a winter prescribed burn, Conservation, P.O. Box 368, Clinton, MO Mead’s Milkweed was found in the St. 64735, 660-885-6981 Francois Mountains of southeast Missouri on igneous substrates on a lobe of Proffitt There are 59 known sites in Missouri with Mountain know as Weimer Hill. In 1995, the extant Mead’s milkweed populations population was described as "providing the documented within the Missouri Natural largest viable seed source for restoration on 1 Heritage Database. Over the past few acidic, nutrient poor soils ." The Missouri decades periodic monitoring of these sites Department of Natural Resources manages has occurred, with longer term surveys at the igneous glades and associated woodlands Paintbrush Prairie and Taum Sauk State with prescribed fire. The area has had 4 Park. Overall, the majority of Missouri prescribed burns over the past 16 years. populations contain < 15 plants, from initial Stewardship includes monitoring populations surveys in the 1970’s and 1980’s and in of threatened or endangered species to assess recent surveys. Individual prairie management effects. populations that once contained significant stem numbers have declined in total Mead’s milkweed monitoring was initiated in population size, including Paintbrush Prairie, 2001 on Weimer Hill (27 plants) and above with >700 stems in 1983 to < 90 stems in Mina Sauk Falls (6 plants). Characteristics each of the last 10 years. An effort began in recorded included stem height or length, leaf 2005 through 2006, to survey all known number, width of the widest leaf, and total Missouri populations, with 36 locations number of flowers produced. surveyed to date. Limited additional surveys

3 of undocumented sites occurred. In 2005, 10 infrequent natural reproduction, and many of 34 prairie and glade locations surveyed eastern populations fail to produce seeds contained a total of 256 stems, with 15% because they comprise single clones. In an flowering and 13% fruit production (2% of effort to restore viable populations in the all plants). In 2006, 9 of 21 prairie and glade eastern part of its range, a genetically diverse locations contained 561 stems, with 27% ex situ garden population was established flowering and 2% fruit production (<0.01%). from multiple seed sources, and served as a Proffitt Mountain, containing igneous glade propagule source for restoration. Since 1991, populations, resulted in 43% of the total nine restorations have been initiated in stems and 62% of the flowers found in 2006. Illinois and adjacent Indiana, in which Fall and winter burning resulted in the plantings of seeds and 1-year old juveniles greatest stem numbers. However, the lack of have been repeated over time to simulate rain in 2005 and 2006 may have limited recruitment. Plants may be grown to growth, flower and seed production and flowering within three years in cultivation, accounted for the large number of sites with but seedling growth is suppressed by no plants. No new populations were competition under natural conditions, and 12 discovered; while a loss of three populations or more years may be required for seedlings occurred due to fescue conversion and to reach reproductive size in the field. development. Augmentation of genotypic Therefore establishing cohorts by diversity and population size began in 2006 transplanting greenhouse propagated with translocations of 38 propagated plants juveniles is more efficient than planting of from Miami Co., KS to Wah’ Kon-Tah seeds. However, after initial transplant Prairie, St. Clair Co., MO. Further mortality, survivorship is similar in plants translocation efforts will continue with seed established from seed or planted juveniles. collected from two Missouri prairies (Dade Natural seed production has occurred and Cass Co.) to evaluate individual repeatedly at one restoration site, indicating population response to introduced genotypes. that genetic diversity may be sufficient to overcome self-incompatibility in restorations. Low fecundity and slow seedling growth in Because Mead's milkweed requires many Mead’s milkweed: limits to population years to reach maturity and rarely growth and ability to produce reproduces, seedling and juvenile transition demographic models stages are missing from matrix models required to estimate population growth. For Tim Bell, Department of Biological this reason it is impossible to project whether Sciences, Chicago State University, 9501 the restorations have reached short-term or South King Drive, Chicago, IL, 60628 & The long-term persistence. However, we used Morton Arboretum, 4100 Illinois Route 53, composite matrices of 6 years of transplant Lisle, IL 60532, [email protected] and seedling survivorship data to analyze Marlin Bowles, The Morton Arboretum, elasticity and variance to mean ratios (V/M). 4100 Illinois Route 53, Lisle, IL 60532, High V/M indicated that environmental [email protected] stochasticity, driven by annual variation in precipitation, may be strong in these Mead’s milkweed (Asclepias meadii) is a restorations. Matrices had G/L/F elasticity long-lived self-incompatible iteroparous herb ratios similar to those expected for late- of late-successional midwestern tallgrass successional plants. Interpretation of A. prairie and glades. This species has meadii elasticities supported a logical

4 management need to increase growth despite height, leaf width, and stem diameter. The limitations due to slow growth, low fecundity mean number of ramets per clone for the and lack of data from natural populations. monoculture and prairie settings was 2.4 and 1.3, respectively. No prairie ramets flowered Propagation and establishment of Mead’s until year 7, while monoculture plants first milkweed flowered in year 2. The peak flowering period was in May. During year 6, 73.7% of John M. Row and Richard L. Wynia, the more robust ramets in the monoculture USDA-Natural Resources Conservation produced 199 flowers yielding 14 pods, 14.2 Service, Manhattan Plant Materials Center, buds per , 1.4 pods per plant, and 80.8 Manhattan, KS 66502, seeds per pod. Mature monoculture plants [email protected], exhibited greater leaf area and stem diameter [email protected] to support seed production while prairie plants tended to exhibit juvenile The Kansas Biological Survey, Lawrence, morphological characteristics. Kansas, and USDA-Natural Resources Conservation Service’s Plant Materials Introduction to the Natural Heritage Center (PMC) Manhattan, Kansas, teamed up Program database on Mead’s milkweed to assist with development of a recovery plan Jennifer Delisle, Kansas Biological Survey, to reestablish Mead's milkweed (Asclepias 2101 Constant Avenue, Lawrence, KS meadii Torr. ex Gray), a Federally listed 66047, [email protected] threatened species, to eastern Kansas prairies. The PMC focused on areas where The Kansas Natural Heritage Inventory information about the species was lacking: maintains an integrated database germination requirements, propagation and management system containing establishment techniques, and maintenance comprehensive biological data on the plants, of plant populations. The best germination animals, and natural communities of Kansas. occurred at the 20/24 ˚C 16h/8h (night/day) These databases have been developed over a alternating temperature regime following period of 18 years and continue to be updated periods of cold-moist stratification. The as new information becomes available. The mean germination rate was 95.7%. The system currently contains 155 records of seedlings were transplanted to 10.2-cm3 extant populations of Mead’s milkweed cone-tainers with a success rate of 95%. (Asclepias meadii). Thirty-nine of these Established container stock was transplanted populations were discovered during a prairie into restored tall grass prairie and inventory conducted in five northeast Kansas monoculture settings at Manhattan to counties in 2004-2005. compare cultural techniques in establishment and maintenance of plants. Seedlings were Viability ranks are assigned to populations established on monoculture sites at a success where survey data are available. These ranks rate of 74% compared to 69% on prairie sites help determine conservation priorities and over a two-year period. Established plants in may be useful in determining when recovery the two settings were monitored to observe plan goals have been met. Five populations morphological differences in flowering and in Kansas have an estimated viability of non- populations. “excellent” and six have an estimated Monoculture plants were more robust than viability of “good”. Nearly 40% of all their prairie counterparts in terms of ramet populations have not been assigned viability

5 ranks due to lack of complete survey data. An adaptive framework for managing Surveys to determine the size of known Mead’s milkweed in the face of populations, as well as to locate new uncertainty populations, are needed to create a more complete picture of the status of Mead’s Clinton T. Moore, USGS Patuxent Wildlife milkweed in Kansas. Research Center, Warnell School of Forestry and Natural Resources, University of Mead’s milkweed on private land: Role of Georgia, Athens, GA 30602 conservation easements Kristopher Lah, U.S. Fish and Wildlife Service, Chicago Field Office, 1250 S. Kelly Kindscher and Bernadette Kuhn, Grove, Suite 103, Barrington, IL 60010 Kansas Biological Survey, 2101 Constant Lianne Ball, U.S. Geological Survey Avenue, Lawrence, KS, 66047, Chris Fonnesbeck, Florida Fish and [email protected], [email protected] Wildlife Research Institute In Kansas 93 % of all 155 Mead’s milkweed Christine Hunter, University of Alaska- sites are on private property. Only 5 sites are Fairbanks owned by the state or federal government, Paul McKenzie, U.S. Fish and Wildlife and 4 additional sites have conservation Service easements held by the Kansas Land Trust. Michael Runge, U.S. Geological Survey Tracts of land that harbor Mead’s milkweed Katriona Shea, Pennsylvania State can be protected by purchasing them or by University using conservation easements (which are Leslie TeWinkel, U.S. Fish and Wildlife legal agreements with landowners that Service protect conservation values of the land). We Collaborating scientists and managers from calculate that about $2.7 million would be federal, state, and university institutions are needed to protect half of the Mead’s developing an adaptive decision framework milkweed sites in Kansas with conservation for the recovery of Mead’s milkweed easements (purchased easements at $1000 (Asclepias meadii). Most (>75%) known per acre). Typically, conservation easements populations of the plant occur on private can be purchased at 1/3 or less of the value of lands managed for hay or otherwise receive the land. Creative means of protecting land no formal conservation protection or that contains Mead’s milkweed will need to management. Even on conservation lands, be used to get landowner involvement. In three sources of uncertainty make addition, restoring prairies to connect Mead’s management for recovery of Mead’s milkweed populations will be necessary to milkweed profoundly difficult: (1) structural create viable populations. An example of uncertainty about the key biological how this could be done, will be highlighted mechanisms most limiting to population with an example from Miami County, growth, (2) environmental stochasticity in the Kansas. Conservation of Mead’s milkweed plant’s response to management actions and through the use of conservation easements chance disturbances, and (3) a partially and prairie restoration could help de-list this observable system that could mislead federally-protected species. managers toward poor decisions. Our

framework focuses on the management of

lands where mowing is not practiced, where alternative forms of management (e.g.,

6 burning, augmentation, hand-, experienced staff, and a cadre of scientists etc.) are generally feasible, and where and educators focused on environmental population monitoring is likely to be research and outreach. Two native prairie continued through time. The general areas within KSR holdings, Rockefeller decision problem is how to allocate Native Prairie and the Anderson County management actions among a fixed number Prairie Preserve (ACPP), support Mead’s of sites through time – within the constraint milkweed populations and these areas are of a total budget cap – so that the expected available to researchers. The 10-acre (4-ha) probability of population persistence among Rockefeller Prairie acquired by KSR in 1956 sites is maximized. Persistence probability is and located near KSR headquarters a quantity averaged over all possible decision (Jefferson Co., KS), has a robust Mead’s outcomes induced by uncertainties milkweed population that has been represented in a stage-structured population monitored intensively for more about 15 model. We express structural uncertainty in years. Several scientific papers have resulted the system through competing models that from work with Mead’s milkweed at use parameter values corresponding to Rockefeller Prairie (dealing with population alternative hypotheses about biological estimation and biology of the species) and mechanisms. By assignment of a weight that seeds from the genetically diverse population reflects the relative credibility of each model, have been provided to further conservation optimal management decisions can be efforts elsewhere. Management at obtained for the current degree of uncertainty Rockefeller Prairie has since 1957 consisted among models. Data obtained following the of springtime burns every 1–3 years, with decision are used to adjust the model burns once every two years from 1986– weights, leading to adaptation in the decision present. Woody species have invaded under policy. Whereas this framework could not be this management and a new prescription is feasibly applied to all populations in the proposed for the next three years that will plant’s range, the development, testing, and include a summer disturbance (haying). The reassessment of models in this focused ACPP, about 60 miles (97 km) south of KSR application should yield knowledge usable in headquarters, is owned by The Nature a broader-scale effort. Conservancy who transferred management responsibility for the area to KSR in 2006. Opportunities for conservation and The established goals for the site are research on Mead’s milkweed at the preservation and enhancement of native University of Kansas Field Station and biodiversity, research, and education. Ecological Reserves: Rockefeller Prairie Although the bulk of the 1370-acre (554-ha) and Anderson County Prairie Preserve preserve is grazing land, there is an area of about 100 acres (40 ha) of former hay W. Dean Kettle, Vaughn Salisbury, and meadow where hundreds of Mead’s Sharon Ashworth, Kansas Biological milkweed ramets have been seen. KSR is Survey, 2101 Constant Avenue, Lawrence, now working with TNC and others to KS 66047, [email protected], [email protected], develop a management prescription for the [email protected] former hay meadows. The ACPP and the Rockefeller Prairie, as well as the entire The University of Kansas Field Station and KSR, are available to interested scientists Ecological Reserves (KSR) consists of more and educators for research and teaching, and than 3300 acres (1337 ha) of diverse habitats, to support conservation efforts. facilities for supporting research, an

7