Ackerfield, J. (2015). Flora of Colorado. Fort Worth, Texas: Botanical Institute of Texas Press. 818 pp.

Arnett, Jr., R. H., N. M. Downie & H. E. Jaques (1980). How to know the beetles. Second edition. Dubuque, IA: Wm. C Brown. 416 pp.

Arnett, Jr., R. H. (2000). American Insects: A handbook of the insects of America north of Mexico. Second edition. Boca Raton, FL: CRC Press.

Ballinger, R. E. & J. D. Lunch (1983). How to know the amphibians and reptiles. Dubuque, IA: Wm. C. Brown. 229 pp.

Barnes, E. H. (1968). Atlas and manual of plant pathology. New York: Plenum Press. 325 pp.

Beug, M. W., A. E. Bessette & A. R. Bessette (2014). Ascomycete fungi of North America: a mushroom reference guide. Austin: University of Texas Press. 488 pp.

Bidartondo, M. I. & T. D. Bruns (2001). Extreme specificity in epiparasitic Monotropoideae (Ericaceae): widespread phylogenetic and geographical structure. Molecular Ecology 10: 2285–2295.

Bland, Roger G. & H. E. Jaques (1978). How to know the insects. USA: WCB/McGraw-Hill. 407 pp.

Booth, E. S. (1982). How to know the mammals. Fourth Edition. USA: Wm. C. Brown. 198 pp.

Chadde, S. W. (2017). Prairie plants of Illinois. Lexington, KY: Pathfinder Books. 289 pp.

Chicago Botanic Garden (continuously updated). Homepage and website. Retrieved July 31, 2018 from (http://www.chicagobotanic.org).

Crowell, I. H. (1934). The hosts, life history and control of the cedar-apple rust fungus Gymnosporangium juniperi-virginianae Schw. Journal of the Arnold Arboretum 15: 163–23.

Dey, D. C. (2014). Sustaining oak forests in eastern North America: regeneration and recruitment, the pillars of sustainability. Forest Science 60: 926–942.

Donley, R., J. V. Jalava & J. van Overbeeke (2013). Management plan for the green dragon (Arisaema dracontium) in Ontario. Ontario Management Plan Series. Retrieved September 4, 2020 from (https://files.ontario.ca/environment-and-energy/species-at-risk/mnr_sar_mtpln_grndrgn_en.pdf).

Dunn, J. L. & J. Alderfer (2009). Illustrated birds of North America. Hong Kong: National Geographic Society. 502 pp.

Eddy, S. & J. C. Underhill (1978). How to know the freshwater fishes. USA: Wm. C. Brown. 215 pp.

Elliott, L., C. Gerhardt & C. Davidson (2009). The frogs and toads of North America. Boston: Houghton Mifflin Harcourt. 343 pp.

Ernst, C. H. & J. E. Lovich (2009). Turtles of the United States and Canada. Second edition. Baltimore: Johns Hopkins University Press. 827 pp.

Farr, M. L. (1981). How to know the true slime molds. Dubuque, IA: Wm. C. Brown. 132 pp.

Flockhart, D. T. T., L. P. Brower, M. I. Ramirez, K. A. Hobson, L. I. Wassenaar, S. Altizer & D. R. Norris (2017). Regional climate on the breeding grounds predicts variation in the natal origin of monarch butterflies overwintering in Mexico over 38 years. Global Change Biology 23: 2565-2576.

Harlow, W. M. (1946/1959). Fruit key and twig key to trees and shrubs. New York: Dover. 56 pp.

Havens, K., C. L. Jolls, J. E. Marik, P. Vitt, A. K. McEachern & D. Kind (2012). Effects of a non-native biocontrol weevil, Larinus planus, and other emerging threats on populations of the federally threatened Pitcher's thistle, Cirsium pitcheri. Biological Conservation 155: 202–211.

Heil, K. D., S. L. O'Kane, Jr., L. M. Reeves & A. Clifford (2013). Flora of the Four Corners region: Vascular plants of the San Juan River drainage, Arizona, Colorado, New Mexico, and Utah. St. Louis: Missouri Botanical Garden Press. 1098 pp.

Hilty, J. (2019–2021). Illinois Wildflowers. Retrieved 3 July, 2021 from (http://www.illinoiswildflowers.info).

Horn, D. J. (2012). Moths of Ohio field guide. Ohio Division of Wildlife. Retrieved July 26, 2017 from (http://wildlife.ohiodnr.gov/portals/wildlife/pdfs/publications/id%20guides/pub5467.pdf).

Hsiang, T. & X. L. Tian (2007). Sporulation and identity of tar spot of maple in Canada. Acta Silvatica et Lignaria Hungarica, special edition: 71-74.

Hudler, G. W., S. Jensen-Tracy & M. T. Banik (1998). Rhytisma americanum sp. nov.: a previously undescribed species of Rhytisma on maples (Acer spp.). Mycotaxon 68: 405-416.

Ing, B. (2020). The Myxomycetes of Britain and Ireland: An identification handbook. Great Britain: Richmond Publishing. 374 pp.

International Union for Conservation of Nature and Natural Resources (IUCN) (continuously updated). The IUCN red list of threatened species. Retrieved 30 May, 2020 from (http://iucnredlist.org)

Iowa State University Department of Entomology (2017). Bugguide. Retrieved 8 September, 2017 from (http://bugguide.net)

James, D. G., ed. (2017). The book of caterpillars: A life-size guide to six hundred species from around the world. Chicago: University of Chicago Press. 656 pp.

Jaques, H. E. (1947). How to know the land birds. Dubuque, IA: Wm. C. Brown. 196 pp.

Jones, G. N. (1971). Flora of Illinois. Notre Dame, IN: U Notre Dame P. 401 pp.

Jones, R. L. (2005). Plant life of Kentucky: an illustrated guide to the vascular flora. Lexington, KY: University Press of Kentucky. 835 pp.

Kaston, B. J. & E. Kaston (1953). How to know the spiders. Dubuque, IA: Wm. C. Brown. 220 pp.

Kershaw, L. (2007). Trees of Illinois. Auburn, WA: Lone Pine Publishing. 304 pp.

Kricher, J. & Morrison, G. (1988). A field guide to eastern forests. New York: Houghton Mifflin. 488 pp.

Kuo, M. & A. S. Methven (2014). Mushrooms of the Midwest. Urbana, IL: University of Illinois Press. 427 pp.

Kuo, M. (2017). MushroomExpert.Com. Retrieved 23 June, 2017 from (www.mushroomexpert.com).

Kurz, D. (2014). Illinois wildflowers. Pettigrew, AR: Tim Ernst Publishing. 256 pp.

Lotts, K. & T. Naberhaus, coordinators (2017). Butterflies and moths of North America. Retrieved July 26, 2017 from (http://www.butterfliesandmoths.org/).

Miller, H. A. & H. E. Jacques (1978). How to know the trees. USA: Wm. C. Brown. 263 pp.

Milne, L. & M. Milne (1980). National Audubon Society field guide to North American insects and spiders. New York: Alfred A. Knopf. 989 pp.

Minnis, A. M., A. R. McTaggart, A. Y. Rossman & M. C. Aime (2012). Taxonomy of mayapple rust: the genus Allodus resurrected. Mycologia 104: 942–950.

Mohlenbrock, R. H. (2006). Forest trees of Illinois. Springfield, IL: Illinois Department of Natural Resources. 331 pp.

Mohlenbrock, R. H. (2014). Vascular flora of Illinois: a field guide. Fourth edition. USA: Southern Illinois University Press. 536 pp.

Murie, O. J. (1982). A field guide to animal tracks. Second edition. Boston: Houghton Mifflin. 375 pp.

Niblett, C. (2017). The Curious Observer's Guide to Slime Mold of UC Santa Cruz and Beyond. USA: UCSC Natural Reserves. 77 pp.

Odonata Central (continuously updated). Retrieved July 20, 2017 from (http://www.odonatacentral.org/).

Parker, M. A. (1987). Pathogen impact on sexual vs. asexual reproductive success in Arisaema triphyllum. American Journal of Botany 74: 1758-1763.

Paulson, D. (2011). Dragonflies and damselflies of the east. Princeton, NJ: Princeton University Press. 538 pp.

Peattie, D. C. (1948/1991). A natural history of trees of eastern and central North America. Boston: Houghton Mifflin. 606 pp.

Peterson, R. T. (1980). A field guide to the birds of eastern and central North America. Boston: Houghton Mifflin. 384 pp.

Phillips, C. A., R. A. Brandon & E. O. Moll (1999). Field Guide to Amphibians and Reptiles of Illinois. Champaign, IL: Illinois Natural History Survey.

Pohl, R. W. (1954). How to know the grasses. USA: Wm. C. Brown Company Publishers. 200 pp.

Preston, R. J. Jr. (1989). North American trees exclusive of Mexico and tropical Florida. Ames, IA: Iowa UP. 407 pp.

Retter, M. L. P. (2017). Field guide to birds of Illinois. New York: Scott & Nix. 376 pp.

Rodewald, P. G., Ed. (2018). The Birds of North America. Ithaca: Cornell Lab of Ornithology. Retrieved April 21, 2018 from (https://birdsna.org).

Schneider, A. (2019). Wildflowers, ferns, and trees of Colorado, New Mexico, Arizona, and Utah. Retrieved September 18, 2019 from (http://www.swcoloradowildflowers.com).

Scott, J. A. (1986). The butterflies of North America. Stanford, CA: Stanford University Press. 583 pp.

Shupe, S. (2019). Illinois wildlife encyclopedia: An illustrated guide to birds, fish, mammals, reptiles, and amphibians. New York: Skyhorse Publishing. 236 pp.

Sibley, D. A. (2009). The Sibley guide to trees. New York: Alfred A. Knopf. 425 pp.

Sibley, D. A. (2014). The Sibley guide to birds. Second edition. New York: Alfred A. Knopf. 599 pp.

Smith, T. W., C. Rothfels & E. Oberndorfer (2006). COSEWIC assessment and update status report on the American columbo Frasera caroliniensis in Canada. Ottawa. 27 pp. Retrieved 18 September 2019 from the Government of Canada website.

Stephenson, S. L. & Stempen, H. (2000). Myxomycetes: A handbook of slime molds. Portland: Timber Press. 183 pp.

Threadgill, P. F., J. M. Baskin & C. C. Baskin (1981). The ecological life cycle of Frasera caroliniensis, a long-lived monocarpic perennial. The American Midland Naturalist 105: 277–289.

United States Department of Agriculture, Natural Resources Conservation Service (continually updated). PLANTS database. Retrieved 3 July, 2021 from (https://plants.usda.gov).

Voss, E. G. & A. A. Reznicek (2012). Field manual of Michigan flora. USA: University of Michigan Press. 990 pp.

Whitaker, J. O. Jr. (1996). National Audubon Society field guide to North American mammals. New York: Alfred A. Knopf. 937 pp.

Wilkinson, R. E. & H. E. Jaques (1972). How to know the weeds. Second edition. Dubuque, IA: Wm. C. Brown. 232 pp.

Zaya, D. N., I. S. Pearse & G. Spyreas (2017). Long-term trends in Midwestern milkweed abundances and their relevance to monarch butterfly declines. Bioscience 67: 343-356.

Kuo, Michael & Melissa Kuo (2018). References. Retrieved from the midwestnaturalist.com website: www.midwestnaturalist.com/references.html

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