Document Type



invasive plants, natural areas, conservation, weed control, Iowa flora, exotic species


Non-native, invasive forb species have been a problem in Iowa since the earliest decades of Iowa's European settlement. The history of studies of Iowa's invasive plants began with L. H. Pammel, and these studies continue to present. Three tables cite the occurrence of many of these species in the state, with Table 1 listing 93 non-native forbs reported by Pammel, Table 2 citing ten invasive forbs of natural areas, and Table 3 adding 38 observed or potential aggressive species of Iowa's anthropogenic and natural areas.

There has been a divergence of interest and research in the management of invasive species of agricultural and horticultural areas versus natural areas. The problems of applying our weed laws, in particular the Iowa Noxious Weed Law, to natural areas include both a failure to accurately identify invasive and native species, and collateral damage to desirable species in the natural areas resulting from weed control efforts. Two models for control of invasive species in natural areas are provided.

In light of changing attitudes toward invasive species and our natural areas, better education, training, and coordination are suggested as ways of improving our management of them in Iowa. Continuing efforts to restore and reconstruct natural areas and the use of native, rather than non-native, species in horticultural settings are also encouraged as possible ways to slow the introduction and spread of invasive plant species.

Publication Date

December 2001

Journal Title

Journal of the Iowa Academy of Science





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© Copyright 2001 by the Iowa Academy of Science, Inc.



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