Ecological Review of Maxton Plains Alvar

Prepared by: Jesse M. Lincoln Michigan Natural Features Inventory P.O. Box 13036 Lansing, MI 48901-3036

For: Michigan Department of Natural Resources Wildlife Division; C/O Sherry MacKinnon February 19, 2019

Report No. 2018-24 ACKNOWLEDGEMENTS

Funding for this project was provided by the Wildlife Division of the Michigan DNR. We express our sincere gratitude to the numerous DNR staff that helped administer and guide this project, including: Michael Donovan, Mark Sargent, Sherry MacKinnon, Patrick Lederle, Ann LeClaire-Mitchell, and Steve Chadwick. This report relies on data collected by many present and former MNFI fi eld scientists, especially: Dennis Albert, Mike Penskar, Joshua Cohen, and Bradford Slaughter. For their support and assistance throughout this project, we thank our MNFI colleagues, especially Ashley Adkins, Rebecca Rogers, Helen Enander, Phyllis Higman, Kraig Korroch, Mike Monfi ls, Nancy Toben, Clay Wilton, Aaron Kortenhoven, and Brian Klatt. Joshua Cohen, Tyler Bassett, and Gregory Norwood provided valuable comments and suggestions during the editing process and their input is greatly appreciated. Gail Ledy at the Drummond Island Historical Museum off ered important information and connected me with Gary Cloudman. Mr. Cloudman provided invaluable insight into the history of Native Americans on the island and was very generous with his time. Tom Lincoln was an outstanding fi eld assistant.

Suggested Citation: Lincoln, J.M. 2018. Ecological Review of Maxton Plains Alvar. Michigan Natural Features Inventory Report Number 2018-24, Lansing, MI. 28 pp.

Cover Photo: Maxton Plains Alvar, Drummond Island. Photo by Jesse M. Lincoln, 2018

Copyright 2018 Michigan State University Board of Trustees. Michigan State University Extension programs and materials are open to all without regard to race, color, natural origin, gender, religion, age, disability, political beliefs, sexual orientation, marital status, or family status. TABLE OF CONTENTS

INTRODUCTION...... 1 Ecoregional Context ...... 1 Natural Community Description ...... 3 History ...... 5

METHODS ...... 7

RESULTS ...... 9 Description of Vegetation ...... 9

DISCUSSION ...... 12 Element Occurrence Rank ...... 12 Management Considerations ...... 13 Conclusions ...... 17

LITERATURE CITED ...... 18

APPENDIX ...... 19 INTRODUCTION There are many important ecological features within Management Unit, Forest Resource Division (FRD) and is the Great Lakes basin. Among the more unique natural jointly managed with the Wildlife Division (WLD) and The communities is the globally-rare alvar. Known from three Nature Conservancy, which owns adjacent areas of high- areas of the world and found locally within the Great quality alvar. Lakes region, alvar is characterized by fl at limestone bedrock with absent or thin soils. Alvar in Michigan is a The purpose of this report is to update the Element critically imperiled community type with fi ve documented Occurrence (EO) data for Maxton Plains after an ecological examples. Alvar and related limestone bedrock ecosystems evaluation and provide ongoing guidance to the DNR are restricted in Michigan to the Niagaran escarpment in on managing the ecological integrity of this unique the southeastern UP and along the Escanaba River. The resource. This report provides descriptions of the alvar’s most extensive areas of alvar in the state occur in the current conditions, historic disturbances, and threats, northern portion of Drummond Island at the site known as and management considerations. The report is intended Maxton Plains, the focus of this report. Of all the potential to complement existing management plans as well as ecological reference areas on state forest lands, Maxton supplement past reports. Plains alvar on Drummond Island was ranked as the highest stewardship priority (Cohen et al. 2009). Ecoregional Context The various ecoregions of Michigan have been classifi ed The Michigan Department of Natural Resources (DNR), based on glacial features, climate, and characteristic owns and manages large portions of Drummond Island, ecosystems. Maxton Plains occurs within the Niagaran including some of the most signifi cant areas of Maxton Escarpment and Lake Plain Subsection and the St. Ignace Plains. The Maxton Plains Ecological Reference Area Sub-Subsection (VIII.1.1). occurs within the Sault Sainte Marie State Forest

Figure 1. Maxton Plains alvar (in green) occurs in the northern portion of Drummond Island, which occurs in northern Lake Huron.

Page-1 - Ecological Review of Maxton Plains Alvar. MNFI 2018 Figure 2. Statewide distribution of alvar (Albert et al. 2008).

Page-2 Ecological Review of Maxton Plains Alvar. MNFI 2018 - Page-2 This Sub-Subsection is typifi ed by sandy lake plain and occurring on broad, fl at expenses of limestone (Kost et al. limestone bedrock at or near the surface. Variation of 2007, Cohen et al. 2015). historic lake levels has led to features originating from wind-blown sand along historic and current shoreline, such Alvar is characterized by shallow, mildly- to moderately- as sand dunes, dune and swale complexes, and transverse alkaline soil over bedrock. These systems are typically dunes within historic lake plain. The entire Sub-subsection subjected to seasonal environmental extremes of soil is underlain by sedimentary bedrocks, principally limestone saturation or inundation in the spring followed by drought and dolomite (405 to 500 million years old). Areas of in the summer. The combination of shallow soil and limestone bedrock form the Niagaran Escarpment, which extreme fl uctuations in soil-water availability plays an is locally exposed as cliff s and natural pavement along the important role in controlling the establishment of trees and Lake Michigan and Lake Huron shorelines. Alvar exists patterning of vegetation. Historically, fi re probably also exclusively where limestone bedrock is exposed or occurs played an important role in limiting tree establishment and under very shallow soils. Natural communities associated maintaining open grasslands (Albert 2006). with shallow soils over limestone or exposed limestone bedrock, including alvar, are concentrated on Drummond Alvar is dominated primarily by grasses and sedges. Island (Albert 1995, 2006). Mosses and lichens dominate in the driest areas and on exposed bedrock. Scattered shrubs and trees persist in Natural Community Description areas where soils develop, especially in cracks that provide Alvar is a term applied broadly to describe a suite of natural additional moisture. The system grades into limestone communities occurring on limestone bedrock (Reschke bedrock glade, limestone bedrock lakeshore, boreal forest, et al. 1999). This report uses MNFI’s specifi c natural wet meadow, northern shrub thicket, and Great Lakes community description of alvar as a graminoid-dominated marsh. community with scattered shrubs and sometimes trees

Photo 1. The open, graminoid-dominated alvar occurs where the limestone bedrock is exposed or overlain by shallow soils. Cracks in the bedrock are visible as long, linear features. The system transitions to limestone bedrock glade and boreal forest where soils are deeper.

Page-3 - Ecological Review of Maxton Plains Alvar. MNFI 2018 Photo 2. The limestone bedrock that is responsible for the existence of alvar is visible across the island. Sometimes the outcrops are quite visually dramatic, as with the northeastern shoreline (pictured above). The collection of limestone bedrock communities on Drummond Island are unique within Michigan and very rare across the world.

Photo 3. Fire scars are visible on some trees within the alvar and in adjacent forests. The trees were never older than 100 and the fi res likely correspond to European settlers burning the alvar for cattle. Compartment 45001, Stand 1.

Page-4 Ecological Review of Maxton Plains Alvar. MNFI 2018 - Page-4 History The alvar areas surveyed for this review have a long and of fi re within the alvar can be supposed given the proximity complex human history. Archeological investigations to a large settlement, the propensity for indigenous cultures have provided evidence of Native American presence to manage landscapes with fi re, and the presence of many on Drummond Island for at least 1500 years (Branstner plant species within the alvar that occur in other fi re- 1992) until settlers forced them off of the island around dependent natural communities. 1830. Michigan State University conducted extensive archaeological surveys and determined that there was There is a long history of logging on the island and state a large and permanent settlement on the north shore of forest lands continue to be harvested. The focus of these Maxton Bay at the current residence of Gary Cloudman logging eff orts has been in the areas of deeper soils that whose great-grandparents settled the property in 1894. support maple, oak, and pine. Many nearby islands were His family had uncovered evidence of the settlement cleared to make charcoal for steam ships in the Great Lakes for years, including hundreds of artifacts and a burial and the expanses of boreal forest on the Drummond Island mound. The discovery of the burial mound led them to may have been cleared for that purpose, thereby potentially contact university archaeologists and subsequent surveys altering the extent of the alvar within that matrix. established the current timeline of occupancy (Gary Cloudman, personal communication 2018, Branster 1992). The earliest available aerial imagery for the island is from an eff ort to survey the entire state during the 1930s. Grazing occurred on Maxton Plains for several decades into Comparing this imagery to current satellite imagery, the the 20th century. These places were also burned annually extent of the alvar has not been signifi cantly reduced or semi-annually to make vegetation more palatable for during the past 80 years (Figures 3 and 4). This is likely a cattle or sheep (Gail Ledy, personal communication 2018). result of the seasonal inundation and drought conditions Although there is no defi nitive evidence that resident acting together to slow successional transition beyond open Native Americans burned the alvar on Drummond Island, grassland. occasional fi res within the alvar were likely. Past incidence

Photo 4. Glacial erratics are common throughout Maxton Plains and provide critical habitat for nesting ants which are a valuable food source for the island’s bear population.

Page-5 - Ecological Review of Maxton Plains Alvar. MNFI 2018 Figures 3 and 4. Comparing imagery from 1938 (above) and 2016 (below), the loss of alvar to boreal forest is less pronounced than other grassland systems around the state during the same period of time. This is a result of the hydro- xeric nature of the natural community type: seasonal inundation and growing season drought limit encroachment of woody species. The observable loss of alvar is likely due, in part, to changes in hydrology associated with roads and ditches. Decreased inundation appears to facilitate the encroachment of woody species. The openings may have also been historically more expansive as a result of timber harvest, grazing, or potentially historic burning. Generally, the boundaries of the alvar appear to be relatively stable as a result of the harsh growing conditions.

Page-6 Ecological Review of Maxton Plains Alvar. MNFI 2018 - Page-6 METHODS Throughout this report, the high-quality natural community Ecological fi eld surveys were conducted over three days and rare species are referred to as “elements” and their in August of 2018. Qualitative meander surveys were documented occurrence at a specifi c location is referred to employed to assess the natural community classifi cation, as an “element occurrence” (EO). The Maxton Plains alvar ecological boundaries, and ranking of this alvar. Vegetative EO was evaluated employing Natural Heritage and MNFI structure and composition, soils, landscape and abiotic methodology, which considers three factors to assess a context, threats, management needs, and restoration natural community’s ecological integrity or quality: size, opportunities were all described. The primary goal of landscape context, and condition (Faber-Langendoen et this survey eff ort was to provide resource managers al. 2008, 2015). If a site meets defi ned requirements for and planners with updated information on this natural these three criteria (MNFI 1988), it is categorized as a community EO. This information is critical for facilitating high-quality example of that specifi c natural community site-level decisions about conserving biodiversity, type, entered into MNFI’s database as an EO, and given prioritizing protection, management, and restoration, a rank of A to D based on how well it meets the above monitoring the success of management and restoration, and criteria. To assess natural community size and landscape informing landscape-level biodiversity planning eff orts. context, a combination of fi eld surveys, aerial photographic interpretation, and Geographic Information System (GIS) analysis was employed.

This ecological fi eld survey involved:

a) compiling comprehensive plant species lists and noting dominant and representative species b) describing site-specifi c structural attributes and ecological processes c) measuring tree diameter at breast height (DBH) of representative canopy trees and aging canopy dominants d) analyzing soils and hydrology e) noting current and historical anthropogenic disturbances f) evaluating potential threats to ecological integrity g) ground-truthing aerial photographic interpretation using GPS h) taking digital photos both on the ground and remotely using a drone i) surveying adjacent lands to assess landscape context j) evaluating the natural community classifi cation and mapped ecological boundaries k) evaluating the element occurrence rank l) updating element occurrence data for rare plants m) noting management needs and restoration opportunities and evaluating past and current restoration activities and noting additional management needs and restoration opportunities

Following completion of the fi eld surveys, the collected compiled into the Universal Floristic Quality Assessment data were analyzed and transcribed to update the existing Calculator (Reznicek et al. 2014, Freyman et al. 2016) to EO record in MNFI’s statewide biodiversity conservation determine the Floristic Quality Index (FQI). Michigan sites database (MNFI 2018). Natural community boundaries with an FQI of 35 or greater possess suffi cient conservatism were mapped and information from this survey was and richness that they are considered fl oristically important used to update the site description, threat assessments, from a statewide perspective (Herman et al. 2001). and management recommendations. Floristic data were

Page-7 - Ecological Review of Maxton Plains Alvar. MNFI 2018 Photos 5 and 6. The alvar is highly variable with many factors infl uencing vegetative composition and structure. Photo 3 (above, Compartment 45002, Stand 16) shows a zone of Calamagrostis canadensis along the southern edge of the openings where the tilt of the bedrock facilitates extended periods of inundation and the accumulation of organic material. The tree line also creates a microclimate more suitable for soil accumulation and the establishment of taller vegetation. Areas of exposed limestone pavement (below, Compartment 45002, Stand 36) features sparser vegetation and a greater proportion of lichens and nonvascular plant life.

Page-8 Ecological Review of Maxton Plains Alvar. MNFI 2018 - Page-8 RESULTS

Maxton Plains was fi rst described and documented as a comprehensive species list). Native graminoids include hair natural community in 1980 and represents a single alvar grass (Deschampsia cespitosa), poverty grass (Danthonia EO. This report is an update to the EO, which was last spicata), prairie dropseed (Sporobolus heterolepis, updated in 2010 and last thoroughly surveyed in 2007 state special concern), Flattened spike rush (Eleocharis (Cohen et al. 2009, MNFI 2018). The alvar occurs as a compressa, state threatened), golden-seeded spike rush (E. series of dozens of graminoid-dominated openings ranging elliptica), several sedges (Carex richardsonii [state special dramatically in size from a couple acres to several hundred concern], Cx. scirpoidea [state threatened], Cx. capillaris, acres. These openings occur in a matrix of limestone Cx. adusta), Dudley’s rush (Juncus dudleyi), ticklegrass bedrock glade and boreal forest and correspond to areas of (Agrostis scabra), little bluestem (Schizachyrium thin soil over limestone bedrock. The species composition scoparium), broom-sedge (Andropogon virginicus), of these openings is also highly variable and is infl uenced panic grass (Dichanthelium implicatum), and prairie by soil depth, degree of inundation, and land-use history. brome (Bromus kalmii). Wetter zones have blue-joint The southern portions of the openings tend to be wetter as (Calamagrostis canadensis), bulrush (Scirpus atrovirens), a result of the subtle tilt of bedrock and the microclimate several sedges (Cx. pellita, Cx. bebbii, Cx. fl ava), rush along the forest edge where the canopy shades the margin (Juncus balticus), fringed brome (Bromus ciliatus), narrow- of the open zones. leaved cotton-grass (Eriophorum angustifolium), native reed (Phragmites australis var. americanus), and twig-rush Description of Vegetation (Cladium marscoides). The highest quality areas are characterized by high herbaceous diversity. Although each opening has its own Forbs include yarrow (Achillea millefolium), upland character, a few dominance patterns emerge at a landscape white goldenrod (Solidago ptarmicoides), fl at-topped scale, primarily associated with soil moisture and depth of white aster (Doellingeria umbellata), common water soils (See Appendix for descriptions of specifi c areas and a horehound (Lycopus americana), rock sandwort (Minuartia

Photo 7. The most intact areas of alvar are dominated by graminoids but also have a robust suite of fl owering plants. Compartment 45002, Stand 16.

Page-9 - Ecological Review of Maxton Plains Alvar. MNFI 2018 Photos 8 and 9. Characteristic structure and composition of vegetation in Maxton Plains.

Page-10 Ecological Review of Maxton Plains Alvar. MNFI 2018 - Page-10 dawsonensis), balsam ragwort (Packera pauperula), Eleocharis species. Non-native species are locally abundant Indian paintbrush (Castilleja coccinea), bastard toadfl ax especially along road margins and include timothy grass (Comandra umbellata), prairie smoke (Geum trifl orum, (Phleum pratensis), bluegrasses (Poa compressa and P. state threatened), small skullcap (Scutellaria parvula, pratensis), spotted knapweed (Centaurea stoebe), curly state threatened), and grass-leaved goldenrod (Euthamia dock (Rumex crispus), clovers (Trifolium repens, T. graminifolia). pratense, and Melilotus albus), and quack grass (Elymus repens). Within the open alvar habitat, trees are usually sparse and generally stunted. Typical species include quaking aspen Some areas appear to be openings that were once (Populus tremuloides), white spruce (Picea glauca), balsam forested, based on presence of old stumps. These areas of fi r (Abies balsamea), tamarack (Larix laricina), and white former forest tend to have lower diversity and a greater cedar (Thuja occidentalis). Tall shrubs include soapberry concentration of the same non-native species and were (Shepherdia canadensis), serviceberry (Amelanchier removed from the areas mapped as high-quality alvar. spicata), and common juniper (Juniperus communis). Low shrubs include shrubby cinquefoil (Dasiphora Maxton Plains alvar was surveyed over the course of three fruitcosa), wild rose (Rosa blanda), fragrant sumac (Rhus days in August of 2018. Floristic data were compiled into aromatica), sand cherry (Prunus pumila), creeping juniper the Universal Floristic Quality Assessment Calculator (Juniperus horizontalis), choke cherry (Prunus virginia), (Reznicek et al. 2014, Freyman et al. 2016). A total of dwarf raspberry (Rubus pubescens), and bearberry 141 plant species were documented with 121 native (Arctostaphylos uva-ursi). Small forested islands occur species and 20 non-native species. The mean coeffi cient of scattered throughout the alvar. conservativism (C) for the alvar is 4.5 and the total fl oristic quality index (FQI) is 53.4. Refer to Appendix 2 for the Some areas appear to have been grazed based on decreased complete fl oristic list and quality assessment. Several rare plant diversity and increased dominance of non-native species have been documented throughout the alvar system. species. These areas generally have a greater abundance of Table 1 provides name, status, and location of these species.

Table 1. Rare plant element occurrences in Maxton Plains alvar. EO Rank categories are as follows: A, excellent estimated viability; B, good estimated viability; C, fair estimated viability; D, poor estimated viability; E, Verifi ed extant (viability not assessed). Status abbreviations: SC, Special Concern and T, Threatened. Asterix associate stands with compartment when species occur in multiple compartments.

First Observation Last Observation Common Name Scientific Name EO ID EO Rank Status Date Date Compartment Stands 3, 6, 16, 45, 48, 126**, 400**, 401**, Richardson's sedge Carex richardsonii 7519 AB SC 1983 2018 45001, 45004** 404** Bulrush sedge Carex scirpoidea 746 A T 1961 2018 45001, 45002* 1, 11*, 16*, 36* Shortstalk chickweed Cerastium brachypodum 17626 H T 1950 1950 45001 36, 38 1, 6, 48, 45, Hill's thistle Cirsium hillii 1092 B SC 1987 2018 45001, 45002* 16*, 33*, 36*, 38* 1, 6, 16, 45, 48, 45001, 45002*, 11*, 16*, 34*, Flattened spike rush Eleocharis compressa 6176 A T 2001 2018 45004** 126**, 401** Prairie smoke Geum triflorum 1819 A T 1981 2018 45002, 45001* 16, 36, 1* 45001, 45002, Occurs in most Small skullcap Scutellaria parvula 1122 AB T 1961 2018 45004 alvar openings. 3, 6, 16, 45, 48, 126**, 400**, Prairie dropseed Sporobolus heterolepis 9343 A SC 1958 2018 45001, 45004* 401**, 404** False pennyroyal Trichostema brachiatum 7427 B? T 1956 1994 45001, 45002* 1, 36

Page-11 - Ecological Review of Maxton Plains Alvar. MNFI 2018 DISCUSSION Element Occurrence Rank This is an A-ranked alvar EO that consists of dozens of expedites the surface fl ow of water. In the absence of spring individual patches of graminoid-dominated openings within inundation, tree and shrub encroachment may occur more a matrix of limestone bedrock glade and boreal forest. This rapidly, shading out many characteristic alvar species. The designation as an “excellent occurrence” indicates that the greatest concentration of invasive species occurs along size and community composition are primarily driven by roads where soil has been disturbed by ditching. Off -road natural processes. Additionally, this community is extensive vehicle (ORV) use disturbs the thin soil and leaves ruts and well-buff ered from anthropogenic disturbance. in wetter areas, increasing the risk of invasive species’ The protection of the alvar is signifi cant for protecting establishment. Glacial erratics are often piled by people regional biodiversity. Individual patches vary in quality to build cairns and this removes habitat for ants, thereby – a few show signs of degradation such that, if they were reducing forage for bear. Insects are a signifi cant resource considered individually, would justify a lower rank. When for bears. Current threats and recommendations for their considered collectively, however, these patches represent an management are discussed below. extremely high-quality natural community characterized by largely unaltered hydrology, expanses of native vegetation Areas with evidence of historical grazing and timbering are that is both diverse within patches (alpha diversity) and often lower quality as indicated by reduced plant diversity varies in composition between patches (beta diversity), and and increased dominance by fewer species, such as (native) generally, few invasive species. At 1551 acres, this is by far Eleocharis species and non-native grasses (e.g., quack grass the largest alvar in the state. There were 121 native species and bluegrass species). Stand 16 in Compartment 45001 observed in Maxton Plains with a total FQI of 53.4, making is an example of an area that appears to have been grazed this a fl oristically signifi cant site within Michigan. and a signifi cant component of non-native species persists throughout this area. Many openings were burned for Despite the high quality of this occurrence of alvar, signs cattle or sheep, though it is unclear how fi re infl uenced the of both historical and ongoing degradation are apparent. system before European settlement. Based on the presence Ditching along roads has impacted hydrology throughout, of stumps, some openings were historically forested and reducing inundation in the spring. This is most apparent have lower diversity and more invasive species. in the western end where a driveway that runs to the lake

Photo 10. Many areas mapped as alvar featured old stumps and these areas were likely historically forested. These zones tend to have lower diversity of herbaceous plants and higher proportion of non-native invasives such as clover, knapweed, timothy, quack grass, bluegrasses, and Queen Anne’s lace. Compartment 45004, eastern portion of Stand 401.

Page-12 Ecological Review of Maxton Plains Alvar. MNFI 2018 - Page-12 Management Considerations The stands with the most intact alvar have the highest concentration of rare species and should be prioritized for management actions. These include Stands 1, 3, and 6 in Compartment 45001 and Stands 16, 33, 34, 36, and 38 in Compartment 45002 (Figures 5 and 6).

Management recommendations are intended to protect native biodiversity and ecosystem integrity. The main management needs in order of importance are to: 1) restrict off -road vehicle use; 2) monitor and control populations of non-native species, especially in the highest quality areas; 3) mitigate impacts of alterations to hydrology; 4) implement prescribed fi re; 5) discourage rock cairns; and 6) pursue additional land acquisition.

The use of ORVs is widespread on this island and a signifi cant threat to the ecological integrity of this EO. ORV action overturns the shallow soil and destroys Photo 11. Areas of alvar that were historically grazed have sensitive root mats of the plant community, leaving the an abundance of native species but are seriously impacted system at an increased vulnerability to the establishment by invasive species such as spotted knapweed, clover, timothy, quack grass, and bluegrasses. Compartment of invasive species. The spread of invasive species is 45001, Stand 16. additionally facilitated by ORVs use as they transport seed to Drummond Island from other areas on the mainland in soil lodged in tire treads.

Photo 12. Roads have signifi cant impacts on the alvar. Locally hydrology is altered by ditches or by roads blocking the fl ow of water. The road in the far western portion of the alvar (pictured above), cuts through the sod and seems to expedite the fl ow of water off of much of the western portion of the EO and the impact should be investigated. Road and ditch maintenance also facilitates the spread of invasive species by continually disturbing soil along the road edges.

Page-13 - Ecological Review of Maxton Plains Alvar. MNFI 2018 Figure 5. The areas of highest quality alvar are highlighted in blue. These openings have the highest concentrations of rare species and should be prioritized for management actions. Stands of interest: Compartment 45001, Stand 1; Compartment 45002, Stands 16, 33, 34, 36, 38.

Figure 6. Additional stands of interest for prioritizing management activities: Compartment 45001, Stands 3 and 6. Stand 6 may be an ideal area for introducing prescribed fi re because of the dominance of prairie dropseed and the presence of Hill’s thistle.

Page-14 Ecological Review of Maxton Plains Alvar. MNFI 2018 - Page-14 Several non-native plants occur through the alvar; though translocate through the porous limestone and aff ect non- their ecological impacts and rate of spread are not well target species. Application of herbicide is currently an understood. Notable non-native species documented accepted control measure of invasive species but long-term during surveys include Canada bluegrass (Poa compressa), success or impacts of treatment beyond target species is not Kentucky bluegrass (P. pratensis), spotted knapweed understood. These control eff orts should be monitored to (Centaurea stoebe), clovers (Melilotus spp. and Trifolium facilitate evaluation of the effi cacy of restoration activities, spp.), common St. John’s-wort (Hypericum perforatum), determine impacts to non-target species, and inform ox-eye daisy (Chrysanthemum leucanthemum), timothy adaptive management. (Phleum pratense), quack grass (Elymus repens), wild carrot (Daucus carota), and hawkweeds (Hieracium spp.). New technology, such as drone monitoring, may be an important tool for understanding threats posed by invasive Within the highest quality areas, these species appear species (Cohen and Lewis 2019, Cohen and Enander to be concentrated along the roads, especially where 2019). Monitoring eff orts should also focus on detection soil has been impacted by ditching. Elsewhere, historic of potential invaders, especially Canada thistle (Cirsium grazing seems to have caused a greater prevalence arvense), reed canary grass (Phalaris arundinacea), and of non-native grasses. Herbicide application should yellow parsnip (Pastinaca sativa) which are currently be prioritized along roads in the highest quality areas invading much of the island and seem compatible with the (Stand 1 in Compartment 45001 and Stands16 and 36 habitat type but have not yet been found within the alvar. in Compartment 45002), particularly where soil was Treatment of these species along S Maxton Road south of mounded for ditching. Knapweed and clovers appear to be the Maxton Plains may be as important as treating existing the invasive species with signifi cant potential impacts and invasives within the alvar to maintain the long-term should be targeted for removal in the highest quality areas ecological integrity of the EO. of alvar mentioned above. Spot-treating with herbicide is preferred over hand-pulling to avoid disturbing the soil. Ditching has altered hydrology throughout the EO, However, timing is critical for these target species and a particularly by reducing the periodicity of inundation wetland-approved herbicide is likely necessary considering in the spring and during rain events. The diversity and the dynamic nature of the system. Herbicide should be composition of alvar results from the dynamic hydrology. applied judiciously to ensure that the herbicide does not Reducing the duration of saturation alters one of the

Photo 13. Roads have signifi cant impacts on the alvar as hydrology is altered by ditches expediting fl ow or by roads blocking the fl ow of water. Invasive species also seem to be concentrated along road margins where soil is disturbed by ditching. Despite that reality, there are extensive areas of high-quality vegetation.

Page-15 - Ecological Review of Maxton Plains Alvar. MNFI 2018 Photos 14 and 15. Impacts from ORVs were apparent throughout the alvar, including some of the most high-quality areas. ORVs are a signifi cant threat to alvar due to the damage incurred to the thin soils that are slow to develop over bedrock. This causes an increased risk to invasive species and can locally alter hydrology due to long-lasting ruts. Aerial photo by Matthew J. Lewis 2018.

Page-16 Ecological Review of Maxton Plains Alvar. MNFI 2018 - Page-16 principal forces infl uencing plant composition. Additional The Nature Conservancy is protecting large areas of high- ditching to improve road conditions will likely further quality alvar on properties adjacent to state-owned lands. degrade the overall structure and composition of the alvar. Additional areas of alvar in the surrounding landscape Because of the complexity of alvar hydrogeomorphology, occur on private lands. We recommend that these areas we recommend a comprehensive analysis to determine be protected through any means necessary, whether which areas have been most impacted by roads and ditches through acquisition or by a partnership with conservation and if corrective measures are feasible. This would also organizations such as The Nature Conservancy. guide future road improvements and mitigate impacts on sensitive areas. Conclusions Alvar is a unique and imperiled community found in Implementation of prescribed fi re is a low priority, only three areas around the world and Maxton Plains especially compared to limiting ORV access and is Michigan’s largest and highest quality example of understanding hydrology. However, prescribed fi re may alvar. The concentration of alvar on Drummond Islands improve habitat for Hill’s thistle, prairie dropseed, prairie harbors considerable biodiversity, especially several rare smoke, and other alvar plants that occur elsewhere in fi re- species. As a grassland ecosystem with thin soils and dependent ecosystems. Burning was historically used by exposed bedrock, alvar is sensitive to hydrological and cattle and sheep ranchers. The proximity of a large native soil disturbance and therefore particularly vulnerable to American village as documented by archeologists from degradation. MSU leads some credibility to the idea that fi re was a prevalent disturbance factor on the alvar before European Protecting the ecological integrity of alvar on Maxton settlement. Plains is paramount. Maxton Plains is emblematic of Drummond Island and the best representation of alvar in Rock cairns occur throughout the site. This piling of rocks the region. The utmost care should be given when decisions for cairn building reduces habitat for insects (e.g., ants), are being made around roads, ditching, timber harvest, which bears depend on as a food source. Cairns should be invasive species management, and ORV access. dismantled to restore ant habitat. Providing educational signage about alvar and numerous species that depend on it may discourage anthropogenic activities that degrade its integrity.

Photo 16. Maxton Plains is one of the most signifi cant natural areas in the Great Lakes region and is emblematic of Drummond Island.

Page-17 - Ecological Review of Maxton Plains Alvar. MNFI 2018 LITERATURE CITED Albert, D.A. 1995. Regional landscape ecosystems of Heyman, W.A., L. Masters, and S. Packard. 2016. The Michigan, Minnesota, and Wisconsin: A working Universal Floristic Quality Assessment (FQA) map and classifi cation. USDA, Forest Service, North Calculator: an online tool for ecological assessment Central Forest Experiment Station, St. Paul, MN. and monitoring. Methods in Ecology and Evolution, Albert, D.A. 2006. Natural Community Abstract for Alvar. British Ecological Society, 7: 380-383. Michigan Natural Features Inventory, Lansing, MI. Herman, K.D., L.A. Masters, M.R. Penskar, A.A. Reznicek, 10 pp. G.S. Wilhelm, W.W. Brodovich, and K.P. Gardiner. Branstner, C.N. 1995. Archaeological Investigations at 2001 fl oristic Quality Assessment with wetland the Cloudman Site (20CH6): A Multicomponent categories and examples of computer applications Native American Occupation on Drummond Island, for the State of Michigan - Revised, 2nd Edition. Michigan 1992 and 1994 Excavations. Department Michigan Department of Natural Resources, Wildlife, of Anthropology, Michigan State University, East Natural Heritage Program, Lansing, MI. 19 pp. + Lansing, MI. appendices. Cloudman, G. 2018. Personal communication with Gary Kost, M.A., D.A. Albert, J.G. Cohen, B.S. Slaughter, R.K. Cloudman. His great-grandparents settled the land Schillo, C.R. Weber, and K.A. Chapman. 2007. where the Native American village once stood. Natural Communities of Michigan: Classifi cation and Cohen, J.G., B.S. Slaughter, and M.A. Kost. 2009. Natural Description. Michigan Natural Features Inventory Community Surveys and Stewardship Prioritization Report Number 2007-21, Lansing, MI. 314 pp. of Potential Ecological Reference Areas on State Ledy, G. 2018. Personal communication with Gail Ledy, Forest Lands. Mighigan Natural Features Inventory, volunteer at the local history museum. Her father, Lansing, MI. 526 pp. living at the time of this communication, would graze Cohen, J.G., M.A. Kost, B.S. Slaughter, and D.A. Albert. cattle on the alvar in the 1930s. 2015. A Field Guide to the Natural Communities Michigan Natural Features Inventory (MNFI). 1988. of Michigan. Michigan State University Press, East Draft criteria for determining natural quality and Lansing, MI. 362 pp. condition grades, element occurrence size-classes Cohen J.G., and H.D. Enander. 2019. Rare coastal and signifi cance levels for palustrine and terrestrial ecosystem monitoring. Michigan Natural Features natural communities in Michigan. Michigan Natural Inventory Report Number 2019-08, Lansing, MI. 60 Features Inventory, Lansing, MI. 39 pp. pp. Michigan Natural Features Inventory (MNFI). 2018. Cohen, J.G., and M.J. Lewis. 2019. Development of an Michigan Natural Heritage Database. Lansing, MI. automated monitoring platform for invasives in Reschke, C., R. Reid, J. Jones, T. Feeney, and H. coastal ecosystems. Michigan Natural Features Potter. 1999. Conserving Great Lakes Alvars: Inventory Report Number 2019-05, Lansing, MI. 95 Final Technical Report of the International Alvar pp. Conservation Initiative. The Natura Conservancy, Faber-Langendoen, D., J. Rocchio, P. Comer, G. Kudray, Chicago, IL. 230 pp. L. Vance, E. Byers, M. Schafale, C. Nordman, E. Reznicek, A.A., M.R. Penskar, B.S. Walters, and B.S. Muldavin, G. Kittel, L. Sneddon, M. Pyne, and Slaughter. 2014. Michigan Floristic Quality S. Menard. 2008. Overview of Natural Heritage Assessment Database. Herbarium, University of Methodology for Ecological Element Occurrence Michigan, Ann Arbor, MI and Michigan Natural Ranking based on Ecological Integrity Assessment Features Inventory, Michigan State University, Methods [Draft for Network Review]. NatureServe, Lansing, MI. http://michiganfl ora.net Arlington, VA. Faber-Langendoen, D., W. Nichols, J. Rocchio, J. Cohen, J. Lemly, and K. Walz. 2015. Ecological Integrity Assessments and the Conservation Value of Ecosystem Occurrences: General Guidance on Core Heritage Methodology for Element Occurrence Ranking. NatureServe, Arlington, VA.

Page-18 Ecological Review of Maxton Plains Alvar. MNFI 2018 - Page-18 APPENDIX

Page-19 - Ecological Review of Maxton Plains Alvar. MNFI 2018