Phenodynamic Analyses of Two First‐year Old Fields

Abstract

Phenological spectra from two adjacent first‐year old fields suggest that phenological events may be directed by the biotic influences of associated species as well as by climatic and edaphic conditions of the region. These two fields possessed similar macroclimatic conditions but had differing soil textures and crop histories. Phenological spectra were developed by observations made on all plant species occurring in fixed quadrats during the duration of this study, April 1, 1970, to October 20, 1970. The phenophases observed were initiation of vegetative growth, time of budding, occurrence of flowering, fruiting sequences, and time of seed set and dissemination. Production studies based on short‐term harvest methods indicated the dominance of Erigeron canadensis in the abandoned soybean field, and Erigeron annus in the abandoned corn field.

Effects of Sevin on Small-Mammal Populations in Agricultural and Old-Field Ecosystems

“…Thus, the agricultural community was dominated by summer annuals, whereas the old-field community was dominated by a combination of summer annuals and perennials (Suttman and Barrett, 1979). In general, species diversity and phenology of old-field plants were similar to that described by Swieringa and Wilson (1972) …”