Present Status of Our Knowledge of the Vascular Plant Flora of Iowa

The flora of Iowa is relatively well known compared to that of some of the southern and western states. Many of the earlier botanists in the state, like Macbride, Shimek, Fitzpatrick, Arthur, Pammel, Cratty, and Conard, collected extensively throughout the state. Much floristic work has been done by other botanists, often in limited areas, during and since their time. There is, however, no modern complete flora of Iowa. There is not even a complete check list of the known vascular plants of the state. Conard\u27s very useful Plants of Iowa (1951) with keys to the more common native and cultivated vascular plants of the state contains the most nearly complete published list of indigenous or naturalized vascular plants in Iowa. Cratty\u27s The Iowa Flora (1933) is an excellent annotated list of the Iowa vascular plants represented in 1932 in the Herbarium of Iowa State College. That herbarium, like all the other Iowa herbaria, lacks, however, many species known to occur in the state. Cratty listed 1608 species and varieties as growing without cultivation in Iowa. An analysis made of his list produced a total of 1450 taxa considered by this writer as distinct species actually native ·or naturalized in the state. In supplements to Cratty\u27s list, Goodman (1940, 1943) and Hayden (1940, 1945) added 75 additional acceptable species, giving a total of 1525 species represented by Iowa specimens at Ames up to 1945