te eee Ua Ue BORN: YB UG Rol N 9 
the Singer Tract a few years ago. Conservation groups are now fighting to 
save it, and the world’s rarest woodpecker, from destruction. 
Traveling across Mississippi and Alabama is very much like journeying 
through parts of Illinois. Plowed fields planted in corn and cotton alternate 
with pasture land; red-headed woodpeckers, sparrow hawks, and eastern 
kingbirds fly from the telephone poles and wires as the station wagon rolls 
by; and the silky webs of tent caterpillars loom omniously in many a 
deciduous tree. Except for the native growths of black jack oak, post oak, 
and short-leaf pine, we might have been in Illinois. 
Onward we sped to Georgia and North Carolina — the land of the 
Piedmont Plateau. The Piedmont Plateau is an ancient peneplain lying 
between the Blue Ridge mountains on the west and the low level coastal 
plain on the east, and extending from Pennsylvania to Alabama. (A pene- 
plain is the term applied to land worn down by erosion to a nearly level 
surface.) This plateau covers a large area and, ecologically, has a history 
all its own. In the early days of settlement, large tracts of forest were 
cleared here for cultivation. Land sold cheaply and little thought was given 
to maintaining soil productivity. Heavy winter rains soon washed away the 
best topsoil from unterraced fields and after several years of cultivation 
without fertilizing, they grew relatively unproductive. It became common 
practice for the farmers to abandon such fields and clear new land. Left to 
themselves, these abandoned fields developed gradually into weed fields and 
later into mature forests. The succession of changes through which they 
passed is fascinating material to the ecologist, and I discovered what was 
to me an amazing story as our group surveyed all the stages in this old 
field-pine succession. 
During the first year of an abandoned field’s existence, many weeds 
invade its boundaries and thrive. in the open sun. All are secondary in 
importance, however, to two main plants, crabgrass and horseweed 
(Digitaria sanguinalis and Leptilon canadense). These two dominate the 
area in numbers and conspicuousness. 
As the field moves into its second year of independent growth, crabgrass 
and horseweed are still abundant, but both are soon overtopped by a species 
of aster (aster ericoides) and cut-leaved ragweed (Ambrosia artemisiifolia) . 
These two herbs, both bushy and ordinarily two to four feet tall, together 
or individually are the character species of two-year fields because of size, 
numbers, and conspicuousness. Many of the plants of the open one-year 
fields are now excluded by shade and competition; others, such as Andro- 
pogon grasses, are just starting to come in, represented by a small cluster 
of a few basal leaves. 
Fields undisturbed for three years or more after abandonment are prac- 
tically always occupied by solid stands of three species of Andropogon grass. 
All other plants are subordinate, and those that have survived grow between 
the massive clumps of the broomsedge and are overtopped for a good part 
of the growing season. 
How long Andropogon dominance is maintained depends upon the prox- 
imity of pine seed supply and also upon seed year. Often within three or 
four years of abandonment seeds have gotten in and seedling pines may be 
