Proceedings of the Iowa Academy of Science Volume 93 Number Article 1986 Preserving Natural Diversity in Iowa's Loess Hills: Challenges and Opportunities Dean M Roosa Donald R Farrar Iowa State University Mark Ackelson Iowa Natural Heritage Foundation Let us know how access to this document benefits you Copyright ©1986 Iowa Academy of Science, Inc Follow this and additional works at: https://scholarworks.uni.edu/pias Recommended Citation Roosa, Dean M.; Farrar, Donald R.; and Ackelson, Mark (1986) "Preserving Natural Diversity in Iowa's Loess Hills: Challenges and Opportunities," Proceedings of the Iowa Academy of Science, 93(3), 163-165 Available at: https://scholarworks.uni.edu/pias/vol93/iss3/9 This Research is brought to you for free and open access by the Iowa Academy of Science at UNI ScholarWorks It has been accepted for inclusion in Proceedings of the Iowa Academy of Science by an authorized editor of UNI ScholarWorks For more information, please contact scholarworks@uni.edu Roosa et al.: Preserving Natural Diversity in Iowa's Loess Hills: Challenges an Proc Iowa Acad Sci 93(3): 163-165, 1986 Preserving Natural Diversity in Iowa's Loess Hills: Challenges and Opportunities DEAN M ROOSA1, DONALD R FARRAR2 , and MARK ACKELSON The Loess Hills of western Iowa, due to their extent and depth, are of national importance for geological reasons They also harbor a large portion of Iowa's remaining biological diversity, the significance of which has been underscored by studies sponsored by the State Preserves Advisory Board during the past several years A complex of rare species of plants and animals exist in the rugged terrain; many are Great Plains species which find their only Iowa stations in these Loess Hills Management problems, such as rapid invasion of prairies by woody species, are manifest in this landform and must be addressed in the near future Land protection measures are being addressed by the Department of National Resources, State Preserves Advisory Board, Iowa Natural Heritage Foundation, the Iowa Chapter of The Nature Conservancy and County Conservation Boards The National Park Service has recently designated over 10,000 acres as a National Natural Landmark INDEX DESCRIPTORS: Loess Hills, Iowa's natural diversity, loess prairie, rare Iowa species The geological significance of Iowa's Loess Hills has been realized since the turn of the century (e.g Bain, 1896, 1898; Owen, 1905; Shimek, 1896, 1907), and the biological significance has been known for nearly as long (e.g Pammel, 1901; Shimek, 1908, 1910, 1911) Because of a long hiatus in scientific studies in the Loess Hills, the State Preserves Advisory Board, in 1980, funded a series of studies designed to underscore the Hills' significance and to provide a basis for preservation Results of these studies culminated in a symposium on the Loess Hills presented at the 96th annual meeting of the Iowa Academy of Science on April 17, 1984 Ten of the resulting papers, surveying the biological diversity of the Loess Hills, were published in the December, 1985 issue of the PROCEEDINGS The current issue is devoted to the Geology, Paleontolgy, and cultural history of the Hills Given the world-wide significance of the loess deposits of western Iowa, it is surprising that there has never been a concerted effort of land protection in this landform region Only in recent years has progress been made in recognizing the Hills' importance through protection efforts Savannas A few savannas remain intact in portions of the Loess Hills, particularly in the southern portion, representing the original transition between the forested southern part and the open grasslands of the northern portion These are becoming invaded by woody shrubs and their integrity is rapidly being compromised Rare species A large number of species uncommon to Iowa have been documented as occurring in the Loess Hills (see this issue and the December, 1985 issue of the PROCEEDINGS) Many of these are Great Plains species with an extension of their distribution reaching Iowa only in the Loess Hills (see for example, Novacek, 1985) A partial list of rare Loess Hills species follows: Mammals Grasshopper mouse Plains pocket mouse Southern bog lemming Cotton rat (Onychomys leucogaster) ( Perognathus flavescens) (Synaptomys cooperi) (Sigmadon hispidus) Reptiles and amphibians DISCUSSION Diversiry in the Loess Hills Prairie In the Loess Hills exists the majority of Iowa's remaining prairie, with elements of the tall-grass and mixed-grass phases dominating much of the rugged landscape The amount of prairie remaining has not been precisely determined Woodlands As shown by original surveyor's notes, woodlands existed at the time of settlement in the southern extreme of Iowa's Loess Hills and along stream courses and sheltered slopes Since then, forest cover has been increasing, providing an unusual opportunity to observe rates of migration of woody species as well as of herbaceous understory plants (Novacek et al 1985) Bur Oaks (Quercus macrocarpa) dominate the forest community, with succession trending toward Basswood (Tilia americana) on mesic slopes Black Maple (Acer nigrum) occurs in Holt County, Missouri (Goodnight, 1964), providing an opportunity to observe whether and at what rate this species will migrate northward into Iowa 1State Ecologist, Wallace State Office Building, Des Moines, IA 50319 Professor, Botany Department, Iowa State University, Ames, IA 50011 Trustee, Iowa Chapter, The Nature Conservancy, 424 10th St., Des Moines, IA 50309 3Associate Director, Iowa Natural Heritage Foundation, 505 Fifth Avenue, Suite 830, Des Moines, IA 50309 Published by UNI ScholarWorks, 1986 Great Plains skink Western spadefoot Great Plains toad Ornate box turtle Prairie rattlesnake ( Eumeces obsoletus) (Scaphiopus bombifrons) ( Bufo cognatus) (Terrepena ornata) ( Crota/is viridis) Butterflies Ottoe skipper (Hesperia ottoe) Birds Chuck-will's-widow ( Caprimulgus carolinensis) Plants Prairie moonwort Tumble grass Sand lily Scarlet globe mallow Sensitive briar Missouri vetch Biscuit root Cobaea penstemon Montaine sedge (Botrychium campestre) (Schedonnardus paniculatus) (Mentzelia decapetela) (Sphaeralcea coccinea) (Schrankia nuitallii) (Astragalus missouriensis) (Lomatium foeniculaceum) (Penstemrm cobaea) ( Carex saximontana) There is a need to locate and protect the best populations of rare Loess Hills species Such protection could come from a variety of strategies including registry through The Nature Conservancy and acquisition by or easement with governmental agencies or private, non-profit organizations such as The Iowa Natural Heritage Foundation and The Nature Conservancy The highest degree of protection is preserve dedication through the State Preserves Advisory Board Proceedings of the Iowa Academy of Science, Vol 93 [1986], No 3, Art 164 PROC IOWA ACAD SCI 93(1986) Documentation of known sites of native Loess Hills biota and discovery of new sites is occurring through natural history surveys, and activities of the Iowa Natural Areas Inventory and the various County Conservation Boards Management considerations A multi-faceted approach is needed for protection of sensitive Loess Hills species Certain species require large, unbroken tracts for longterm existence (Howe et al., 1985; Sampson, 1983) Through efforts of the Department of Natural Resources and the Iowa Chapter of The Nature Conservancy, some large tracts have been acquired The State oflowa owns a 2724 acre ( 1102 ha) tract (Loess Hills Wildlife Area) in Monona County, a tract of 1209 acres (489 ha) in the southern portion (Waubonsie State Park) and 865 acres (350 ha) (Stone State Park) in the northern part The Nature Conservancy, in cooperation with the State of Iowa and the Plymouth County Conservation Board, recently purchased a 792 acre (321 ha) tract (repurchased by the Plymouth CCB in June, 1986) in the extreme northern portion (Five Ridge Prairie, Plymouth County) Advantages of large-tract ownership are (a) relative ease with which certain management methods can be applied (e.g controlled prairie burns for community management) (b) efficacy of re-introduction attempts for extirpated species (e.g Prairie Chickens) (c) ease of law enforcement, and (d) ease of population or community monitoring A strong argument can also be forwarded for protection of small areas which may contain a single species or community-type It is probably more feasible, and certainly more cost-effective, to protect some species, particularly microtines and plants, by acquisition of small areas of suitable habitat This approach also appeals to many landowners who retain only small tracts of native habitat due to agricultural land-use However, relatively little is known about size versus community stability (i.e how large a community must be to survive over hundreds of years) or populaton size versus stability (e.g how long a small population of a microtine may survive without infusion of new genetic material from outside populations) Both of these two approaches must be used for some species For example, with migrating birds, the large areas are needed to provide safe stopover sites, but it is the smaller areas which provide a "corridor" for the species' movements The Loess Hills provide an important opportunity for phytogeographical analysis (Novacek, 1985), and if further migration of vascular plants is to occur, there must also be a sufficient corridor of protected native habitats There is a basic framework for such a matrix of large areas connected by smaller areas in the Loess Hills (Fig 1), but it is probably not yet sufficient for long-term biological stability Equally as important as acquisition of adequate land for preservation of biotic diversity is proper management of these acquisitions In addition, private landowners need assistance in good management practices The Loess Hills Landform was historically nearly treeless, except for the extreme southern part This was probably due to a combination of fires and exposure of slopes to sun and drying winds Since settlement, woody vegetation has increased dramatically, with shrubs such as rough-leaved dogwood (Cornus drummondii), smooth sumac (Rhus glabra) and various tree species invading the prairies It has been estimated (Heineman, 1982) that this invasion by woody species, if allowed to proceed at the present rate, will result in the bluff prairies being converted to successional woodlands in 80 years, at least in the central portion (Monona county) of the Loess Hills To maintain the prairie areas, a more aggressive use of controlled burns or other control measures is indicated Land protection in the Loess Hills: present status, ongoing projects and potential for the future In the 1050 square miles (2720 km ) (672,000 acres) of what is called the Loess Hills Landform Region (see Figs 1, 2, Farrar et al., https://scholarworks.uni.edu/pias/vol93/iss3/9 1985) about 5500 acres (2226 ha) are owned by the State of Iowa and under the jur"sdiction of the Department of Natural Resources, about 2100 acres (850 ha) are owned by the County Conservation Boards of the seven western counties, about 150 acres (61 ha) are owned by The Nature Conservancy, and about 700 acres (284 ha) are owned by the municipalities of Council Bluffs and Sioux City (Fig 1) National Natural Landmark Periodically the National Park Service has shown interest in designating part of the Loess Hills as a National Natural Landmark in recognition of their national significance Following recommendations of an evaluation report (Szymkowicz and Ruhe, 1981), the National Park Service recently designated 10,420 acres (4217 ha) as a National Landmark (see Federal Register for May 3, 1984 for notice) The area exists in two tracts, one north of Turin in Monona County; the other near Little Sioux in Harrison County While this confers no legal protection, it will make clear the fact that the Loess Hills are a nationally prominent feature Formal dedication as a National Natural Landmark occurred on August 11, 1986 Loess Hills Pioneer State Forest The Department of Natural Resources has recently approved a plan to establish an approximate 17 ,000 acre (6800 ha) "Pioneer State Forest" in southern Monona and Harrison Counties This complex will exist in four tracts The first acquisition occurred in August, 1986 If completed and properly managed, these tracts may provide protection for certain sensitive species which require fairly large, unbroken segments of habitat for prolonged survival State Preserve Designation Formal dedication of an area as a State Preserve, which requires approval of the landowner and the State Preserves Advisory Board, and the signature of the Governor of Iowa, confers to the area a special form of protection As described in Chapter 11 lB, Code of Iowa, areas so designated are protected against intrusion, inappropriate land-use, or condemnation, and have the highest form of protection available under Iowa law To date, two areas in the Loess Hills have been so dedicated: the Five Ridge Prairie, purchased by the Nature Conservancy and now owned by the Plymouth County Conservation Board; and the Turin Loess Hills Preserve, owned by the State of Iowa and located in Monona County Agencies, organizations, municipalities, and private landowners should be encouraged to apply for this special form of protection if the holding is of sufficient quality to warrant preserve designation Archaeological, geological, and historical, as well as natural areas are considered for dedication by the State Preserves Advisory Board Educational programs Each year, a "Loess Hills Seminar" is conducted at the Loess Hills Wildlife Area near Onawa in Monona County Sponsored by the Western Hills Education Agency and area conservation organizations, this event is designed to increase the understanding and awareness of the geology, communities, and species of the Loess Hills School groups and other organized groups also gather periodically at Camp Angel, a 500 acre (202 ha) area managed by the Pottawattamie Counry Conservation Board, and located near Crescent, to learn more about the environment, particularly the Loess Hills The Iowa Natural Heritage Foundation has recently commissioned a traveling photographic exhibit entitled "Iowa's Loess Hills" The exhibit, with photographs by Don Pogensee of Ida Grove, brings to life the environment and spirit of this unique area and will be on display throughout Iowa in libraries, galleries, bar\ks, and other public buildings Roosa et al.: Preserving Natural Diversity in Iowa's Loess Hills: Challenges an PRESERVING NATURAL DIVERSI1Y CONCLUSIONS We have a large responsibility in the Loess Hills; the programs initiated will have an influence on all present and future Iowans All Iowans should join in the effort to preserve the natural diversiry of the Loess Hills, thus preserving a window through which we and future generations can view the influence this great landform has had and continues to have on the species inhabiting its wind-blown slopes For more information about the Loess Hills, land protection techniques, or educational programs, individuals may contact their local County Conservation Board, the Department of Natural Resources (Wallace State Office Building, Des Moines), State Preserves Advisory Board (Wallace State Office Building), Iowa Natural Heritage Foundation (505 Fifth Ave Suite 830, Des Moines), or The Nature Conservancy (424 10th St., Des Moines) LITERATURE CITED BAIN, H.F 1896 Geology ofWoodbury County Survey Ann Rept 5:241299 BAIN, H.F 1898 Geology of Plymouth County Iowa Survey Ann Rept 8:315-366 FARRAR, D.R., D.M ROOSA and] C PRIOR 1985 Iowa'sLoessHills - A national treasure Proc Iowa Acad Sci 92:157-158 GOODNIGHT, L.M 1964 Flora of Holt County, Missouri M.S Thesis, University of Missouri, Kansas City HEINEMAN, P.L 1982 Woody plant invasion of Iowa Loess Bluff prairies Master's thesis, Univ of Nebraska, Omaha HOWE, R.W., D.M ROOSA, J.P SCHAUFENBUEL, and W.R SILCOCK 1985 The distribution and abundance of birds in the Loess Hills of western Iowa Proc Iowa Acad Sci 92: 164-175 NOVACEK, ] 1985 The Loess Hills of western Iowa: a problem in phytogeography Proc Iowa Acad Sci 92:213-219 NOVACEK, J.M., D.M ROOSA, and W.P PUSATERI 1985 The vegetation of the Loess Hills landform along the Missouri River Proc Iowa Acad Sci 92: 199-212 OWEN, L.A 1905 Evidence on the deposition ofLoess Am Geo! 35:291300 PAMMEL, L.H 1901 Preliminary notes on the flora of western Iowa Proc Iowa Acad Sci 3:106-135 SAMPSON, F.B 1983 Minimum viable populations - a review Nat Areas ] 3: 15-23 SHIMEK, B 1896 A theory of the loess Proc Iowa Acad Sci 3:82-89 SHIMEK, B 1907 The loess of the Missouri River Proc Iowa Acad Sci 14:237-256 Fig Parks, preserves and natural areas in the Loess Hills Landform Region currently held by the state, counties, and municipalities, and by The Nature Conservancy (DNR =Department of Natural Resources; CCB=county conservation board; TNC=The Nature Conservancy) Five Ridge Prairie 792 acres CCB Stone State Park 865 DNR Sioux City Prairie 154 TNC Sioux City Parks - 500 City Fowler Preserve 50 CCB Hansen Tiber 600 CCB Schoenjahn Wildlife Preserve 126 CCB Whiting Woods 80 CCB Loess Hill Wildlife Area 2724 DNR 10 Turin Loess Hills Preserve 220 DNR 11 Preparation Canyon 344 DNR 12 Murray Hill Lookout CCB 13 Loess Hills Pioneer Forest 17190 (proposed) DNR 14 Gleason-Hubel Wildlife Area 165 CCB, 15 Sawmill Hollow Wildlife Area 155 CCB 16 Smith Wildlife Area 201 DNR 17 Council Bluffs City Parks - 200 City 18 Pony Creek Park 53 CCB 19 Pinky's Glen 48 CCB 20 Waubonsie State Park 1209 DNR Published by UNI ScholarWorks, 1986 165 SHIMEK, B 1908 The genesis of loess a problem in plant ecology Proc Iowa Acad Sci 15:57-75 SHIMEK, B 1910 Botany report, In: Geology of Harrison and Monona Counties Iowa Geo! Survey Ann Rept 20:271-485 SHIMEK, B 191 L The Prairies Bull Lab Nat Hist Univ Iowa 6(2): 169-240 S2YMKOWICZ, M.T and R.V RUHE 1981 A survey of potential natural landmarks, geological themes, western central lowlands Natior'ia! Park System, Washington, D.C I ' ) ,) \ ( ) ( Plymouth ,; J Woodbury Pottawattamie Mi I ls (' Fremont I ,) \ , \ fl ,, _.,,_J ~ 'l Proceedings of the Iowa Academy of Science, Vol 93 [1986], No 3, Art Yucca, typically a western species, graces Iowa's Loess Hills Photo by Carl Kurtz https://scholarworks.uni.edu/pias/vol93/iss3/9 ... al.: Preserving Natural Diversity in Iowa's Loess Hills: Challenges an Proc Iowa Acad Sci 93(3): 163-165, 1986 Preserving Natural Diversity in Iowa's Loess Hills: Challenges and Opportunities DEAN... display throughout Iowa in libraries, galleries, barks, and other public buildings Roosa et al.: Preserving Natural Diversity in Iowa's Loess Hills: Challenges an PRESERVING NATURAL DIVERSI1Y CONCLUSIONS... preserving a window through which we and future generations can view the influence this great landform has had and continues to have on the species inhabiting its wind-blown slopes For more information