Proceedings of the Academy of Science

Volume 93 Number Article 9

1986

Preserving Natural Diversity in Iowa's Hills: Challenges and Opportunities

Dean M. Roosa

Donald R. Farrar Iowa State University

Mark Ackelson Iowa Natural Heritage Foundation

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Recommended Citation Roosa, Dean M.; Farrar, Donald R.; and Ackelson, Mark (1986) "Preserving Natural Diversity in Iowa's : Challenges and Opportunities," Proceedings of the Iowa Academy of Science, 93(3), 163-165. Available at: https://scholarworks.uni.edu/pias/vol93/iss3/9

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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 ACKELSON3

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 Savannas since the turn of the century (e.g. Bain, 1896, 1898; Owen, 1905; A few savannas remain intact in portions of the Loess Hills, Shimek, 1896, 1907), and the biological significance has been known particularly in the southern portion, representing the original transi­ for nearly as long (e.g. Pammel, 1901; Shimek, 1908, 1910, 1911). tion between the forested southern part and the open grasslands of the Because of a long hiatus in scientific studies in the Loess Hills, the northern portion. These are becoming invaded by woody shrubs and State Preserves Advisory Board, in 1980, funded a series of studies their integrity is rapidly being compromised. designed to underscore the Hills' significance and to provide a basis Rare species for preservation. Results of these studies culminated in a symposium A large number of species uncommon to Iowa have been docu­ on the Loess Hills presented at the 96th annual meeting of the. Iowa mented as occurring in the Loess Hills (see this issue and the Academy of Science on April 17, 1984. Ten of the resulting papers, December, 1985 issue of the PROCEEDINGS). Many of these are surveying the biological diversity of the Loess Hills, were published in Great Plains species with an extension of their distribution reaching the December, 1985 issue of the PROCEEDINGS. The current issue Iowa only in the Loess Hills (see for example, Novacek, 1985). A is devoted to the Geology, Paleontolgy, and cultural history of the partial list of rare Loess Hills species follows: Hills. Given the world-wide significance of the loess deposits of western Mammals Iowa, it is surprising that there has never been a concerted effort of Grasshopper mouse ( Onychomys leucogaster) land protection in this landform region. Only in recent years has Plains pocket mouse ( Perognathus flavescens) progress been made in recognizing the Hills' importance through Southern bog lemming (Synaptomys cooperi) protection efforts. Cotton rat (Sigmadon hispidus) Reptiles and amphibians DISCUSSION Great Plains skink ( Eumeces obsoletus) Western spadefoot (Scaphiopus bombifrons) Diversiry in the Loess Hills Great Plains toad ( Bufo cognatus) Prairie Ornate box turtle (Terrepena ornata) In the Loess Hills exists the majority of Iowa's remaining prairie, Prairie rattlesnake ( C rota/is viridis) with elements of the tall-grass and mixed-grass phases dominating much of the rugged landscape. The amount of prairie remaining has Butterflies (Hesperia ottoe) not been precisely determined. Ottoe skipper Woodlands Birds As shown by original surveyor's notes, woodlands existed at the Chuck-will's-widow ( Caprimulgus carolinensis) time of settlement in the southern extreme of Iowa's Loess Hills and Plants along stream courses and sheltered slopes. Since then, forest cover has Prairie moonwort (Botrychium campestre) been increasing, providing an unusual opportunity to observe rates of Tumble grass (Schedonnardus paniculatus) migration of woody species as well as of herbaceous understory plants Sand lily ( Mentzelia decapetela) (Novacek et al. 1985). Bur Oaks (Quercus macrocarpa) dominate the Scarlet globe mallow (Sphaeralcea coccinea) forest community, with succession trending toward Basswood (Tilia Sensitive briar (Schrankia nuitallii) americana) on mesic slopes. Black Maple (Acer nigrum) occurs in Holt vetch ( Astragalus missouriensis) County, Missouri (Goodnight, 1964), providing an opportunity to Biscuit root ( Lomatium foeniculaceum) observe whether and at what rate this species will migrate northward Cobaea penstemon (Penstemrm cobaea) into Iowa. Montaine sedge ( 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 1State Ecologist, Wallace State Office Building, Des Moines, IA 50319 strategies including registry through The Nature Conservancy and 2Professor, Botany Department, Iowa State University, Ames, IA 50011. Trustee, Iowa acquisition by or easement with governmental agencies or private, Chapter, The Nature Conservancy, 424 10th St., Des Moines, IA 50309 non-profit organizations such as The Iowa Natural Heritage Founda­ 3Associate Director, Iowa Natural Heritage Foundation, 505 Fifth Avenue, Suite 830, tion and The Nature Conservancy. The highest degree of protection is Des Moines, IA 50309 preserve dedication through the State Preserves Advisory Board.

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164 PROC. IOWA ACAD. SCI. 93(1986)

Documentation of known sites of native Loess Hills biota and 1985) about 5500 acres (2226 ha) are owned by the State of Iowa and discovery of new sites is occurring through natural history surveys, under the jur"sdiction of the Department of Natural Resources, about and activities of the Iowa Natural Areas Inventory and the various 2100 acres (850 ha) are owned by the County Conservation Boards of County Conservation Boards. 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 Management considerations municipalities of Council Bluffs and Sioux City (Fig. 1). A multi-faceted approach is needed for protection of sensitive Loess Hills species. Certain species require large, unbroken tracts for long­ National Natural Landmark term existence (Howe et al., 1985; Sampson, 1983). Through efforts Periodically the National Park Service has shown interest in of the Department of Natural Resources and the Iowa Chapter of The designating part of the Loess Hills as a National Natural Landmark in Nature Conservancy, some large tracts have been acquired. The State recognition of their national significance. Following recommenda­ oflowa owns a 2724 acre ( 1102 ha) tract (Loess Hills Wildlife Area) in tions of an evaluation report (Szymkowicz and Ruhe, 1981), the Monona County, a tract of 1209 acres (489 ha) in the southern portion National Park Service recently designated 10,420 acres (4217 ha) as a () and 865 acres (350 ha) () in National Landmark (see Federal Register for May 3, 1984 for notice). the northern part. The Nature Conservancy, in cooperation with the The area exists in two tracts, one north of Turin in Monona County; State of Iowa and the Plymouth County Conservation Board, recently the other near Little Sioux in Harrison County. While this confers no purchased a 792 acre (321 ha) tract (repurchased by the Plymouth legal protection, it will make clear the fact that the Loess Hills are a CCB in June, 1986) in the extreme northern portion (Five Ridge nationally prominent feature. Formal dedication as a National Natu­ Prairie, Plymouth County). Advantages of large-tract ownership are ral Landmark occurred on August 11, 1986. (a) relative ease with which certain management methods can be applied (e.g. controlled prairie burns for community management) Loess Hills Pioneer State Forest (b) efficacy of re-introduction attempts for extirpated species (e.g. The Department of Natural Resources has recently approved a plan Prairie Chickens) (c) ease of law enforcement, and (d) ease of popula­ to establish an approximate 17 ,000 acre (6800 ha) "Pioneer State tion or community monitoring. Forest" in southern Monona and Harrison Counties. This complex A strong argument can also be forwarded for protection of small will exist in four tracts. The first acquisition occurred in August, areas which may contain a single species or community-type. It is 1986. If completed and properly managed, these tracts may provide probably more feasible, and certainly more cost-effective, to protect protection for certain sensitive species which require fairly large, some species, particularly microtines and plants, by acquisition of unbroken segments of habitat for prolonged survival. small areas of suitable habitat. This approach also appeals to many landowners who retain only small tracts of native habitat due to State Preserve Designation agricultural land-use. However, relatively little is known about size Formal dedication of an area as a State Preserve, which requires versus community stability (i.e. how large a community must be to approval of the landowner and the State Preserves Advisory Board, survive over hundreds of years) or populaton size versus stability (e.g. and the signature of the Governor of Iowa, confers to the area a special how long a small population of a microtine may survive without form of protection. As described in Chapter 11 lB, , areas infusion of new genetic material from outside populations). so designated are protected against intrusion, inappropriate land-use, Both of these two approaches must be used for some species. For or condemnation, and have the highest form of protection available example, with migrating birds, the large areas are needed to provide under Iowa law. To date, two areas in the Loess Hills have been so safe stopover sites, but it is the smaller areas which provide a dedicated: the Five Ridge Prairie, purchased by the Nature Conser­ "corridor" for the species' movements. The Loess Hills provide an vancy and now owned by the Plymouth County Conservation Board; important opportunity for phytogeographical analysis (Novacek, and the Turin Loess Hills Preserve, owned by the State of Iowa and 1985), and if further migration of vascular plants is to occur, there located in Monona County. Agencies, organizations, municipalities, must also be a sufficient corridor of protected native habitats. There is and private landowners should be encouraged to apply for this special a basic framework for such a matrix of large areas connected by smaller form of protection if the holding is of sufficient quality to warrant areas in the Loess Hills (Fig. 1), but it is probably not yet sufficient for preserve designation. Archaeological, geological, and historical, as long-term biological stability. well as natural areas are considered for dedication by the State Equally as important as acquisition of adequate land for preserva­ Preserves Advisory Board. tion of biotic diversity is proper management of these acquisitions. In addition, private landowners need assistance in good management Educational programs practices. The Loess Hills Landform was historically nearly treeless, Each year, a "Loess Hills Seminar" is conducted at the Loess Hills except for the extreme southern part. This was probably due to a Wildlife Area near Onawa in Monona County. Sponsored by the combination of fires and exposure of slopes to sun and drying winds. Western Hills Education Agency and area conservation organizations, Since settlement, woody vegetation has increased dramatically, with this event is designed to increase the understanding and awareness of shrubs such as rough-leaved dogwood (Cornus drummondii), smooth the geology, communities, and species of the Loess Hills. School sumac (Rhus glabra) and various tree species invading the prairies. It groups and other organized groups also gather periodically at Camp has been estimated (Heineman, 1982) that this invasion by woody Angel, a 500 acre (202 ha) area managed by the Pottawattamie species, if allowed to proceed at the present rate, will result in the bluff Counry Conservation Board, and located near Crescent, to learn more prairies being converted to successional woodlands in 80 years, at least about the environment, particularly the Loess Hills. in the central portion (Monona county) of the Loess Hills. To maintain The Iowa Natural Heritage Foundation has recently commissioned the prairie areas, a more aggressive use of controlled burns or other a traveling photographic exhibit entitled "Iowa's Loess Hills". The control measures is indicated. exhibit, with photographs by Don Pogensee of Ida Grove, brings to life the environment and spirit of this unique area and will be on Land protection in the Loess Hills: present status, ongoing display throughout Iowa in libraries, galleries, bar\ks, and other projects and potential for the future public buildings. In the 1050 square miles (2720 km2) (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 2 Roosa et al.: Preserving Natural Diversity in Iowa's Loess Hills: Challenges an

PRESERVING NATURAL DIVERSI1Y 165

CONCLUSIONS SHIMEK, B. 1908. The genesis of loess a problem in plant ecology. Proc. Iowa Acad. Sci. 15:57-75. We have a large responsibility in the Loess Hills; the programs SHIMEK, B. 1910. Botany report, In: Geology of Harrison and Monona initiated will have an influence on all present and future Iowans. All Counties. Iowa Geo!. Survey Ann. Rept. 20:271-485. Iowans should join in the effort to preserve the natural diversiry of the SHIMEK, B. 191 L The Prairies. Bull. Lab. Nat. Hist. Univ. Iowa. Loess Hills, thus preserving a window through which we and future 6(2): 169-240. generations can view the influence this great landform has had and S2YMKOWICZ, M.T. and R.V. RUHE. 1981. A survey of potential continues to have on the species inhabiting its wind-blown slopes. natural landmarks, geological themes, western central lowlands. Natior'ia! For more information about the Loess Hills, land protection Park System, Washington, D.C. techniques, or educational programs, individuals may contact their local County Conservation Board, the Department of Natural Re­ I sources (Wallace State Office Building, Des Moines), State Preserves ) Advisory Board (Wallace State Office Building), Iowa Natural Heri­ ,)' tage Foundation (505 Fifth Ave. Suite 830, Des Moines), or The \ Nature Conservancy (424 10th St., Des Moines). ( )

LITERATURE CITED ( Plymouth ,; BAIN, H.F. 1896. Geology ofWoodbury County. Survey Ann. Rept. 5 :241- J 299. 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, Woodbury University of Missouri, City. HEINEMAN, P.L. 1982. Woody plant invasion of Iowa Loess Bluff prairies. Master's thesis, Univ. of , Omaha. HOWE, R.W., D.M. ROOSA, J.P. SCHAUFENBUEL, and W.R. SIL­ COCK. 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 . Proc. Iowa Acad. Sci. 92: 199-212. OWEN, L.A. 1905. Evidence on the deposition ofLoess. Am. Geo!. 35:291- 300. 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. 1. Parks, preserves and natural areas in the Loess Hills Landform Region currently held by the state, counties, and municipalities, and by Pottawattamie The Nature Conservancy. (DNR =Department of Natural Resources; CCB=county conservation board; TNC=The Nature Conservancy) 1. Five Ridge Prairie 792 acres CCB 2. Stone State Park 865 DNR 3. Sioux City Prairie 154 TNC 4. Sioux City Parks - 500 City 5. Fowler Preserve 50 CCB Mi I ls 6. Hansen Tiber 600 CCB 7. Schoenjahn Wildlife Preserve 126 CCB 8. Whiting Woods 80 CCB 9. Loess Hill Wildlife Area 2724 DNR 10. Turin Loess Hills Preserve 220 DNR 11. Preparation Canyon 344 DNR (' Fremont 12. Murray Hill Lookout 3 CCB I 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 fl------1 ,, ------18. Pony Creek Park 53 CCB _.,,_J 19. Pinky's Glen 48 CCB ~ 20. Waubonsie State Park 1209 DNR 'l

Published by UNI ScholarWorks, 1986 3 Proceedings of the Iowa Academy of Science, Vol. 93 [1986], No. 3, Art. 9

Yucca, typically a western species, graces Iowa's Loess Hills. Photo by Carl Kurtz.

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