Science Question for Friday, November 13th, 2015
Abandoned cornfields have been the sites of investigations concerning ecological succession, the orderly progression of changes in the plant and/or animal life of an area over time (see Figure 1).
(Note: The plants are ordered according to their appearance during ecological succession.)
During the early stages of succession, the principal community (living unit) that dominates is the pioneer community. Pioneer plants are depicted in Figure 2.
The final stage of ecological succession is characterized by the presence of the climax community, the oak-hickory forest. Figure 3 depicts the gradual change from pine to hardwoods.
Figures adapted from Eugene P. Odum, Fundamentals of Ecology. ©1971 by Saunders College Publishing/Holt, Rinehart, and Winston, Inc.
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On the basis of the data presented in Figure 1, approximately 80 years after the abandonment of cropland, the land would contain:
A. pine seedlings only.
B. oak-hickory hardwood forests only.
C. early invading species like horseweed, aster, and broomsedge.
D. large pine trees with an understory of hardwood trees.
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