Bios 
Disturbing Plants 
Violence is a natural part of all plant communities; a disturbance 
that devastates one species may create opportunities for another 
by Robert E. Cook 
The English painter J. M. W. Tur- 
ner certainly captured the sublime, 
violent power of nature in his art. In 
1810 he exhibited a landscape. Cot- 
tage Destroyed by an Avalanche . ac- 
companied by the following lines: 
The downward sun a parting 
sadness gleams 
Portentous lurid thro' the 
gathering storm; 
Thick drifting snow, on snow. 
Till the vast weight burst 
thro’ the Rocky barrier; 
Down at once, its pine clad forests, 
and towering glaciers fall, 
the work of ages 
Crashing through all! extinction follows 
And the toil, the hope of 
man — o'erwhelms. 
Surging diagonally across the can- 
vas, a rush of rock and white ice carry 
massive boulders down an Alpine slope 
against a wild, darkening sky. Along 
the base of the painting, small, spiky 
conifers accentuate the vast scale of 
the devastation. Amidst these trees, 
a wooden cottage is splintering be- 
neath the ,debris. Turner’s vision of 
a capricious, catastrophic nature 
strongly suggests a revolutionary re- 
action against the classical tradition 
of stability in landscape. In the clas- 
sical style, so characteristic of the Eu- 
ropean painters Claude Lorrain and 
Nicolas Poussin, the quiet, pastoral 
countryside is drawn with strong ver- 
tical and horizontal lines of stately 
foliage and massive architecture, per- 
petuating a sense of order and per- 
manence in nature. 
One might expect to find such strik- 
ingly different interpretations of land- 
scape only among artists. Plant ecolo- 
gists, however, are currently in the 
midst of a similar revolutionary re- 
vision of deeply held convictions con- 
cerning natural vegetation. In particu- 
lar, old notions about the stability of 
the American wilderness before the 
European settlers arrived have been 
severely shaken by reconstructions of 
vegetational history. Before discussing 
these new views, however, I should 
sketch the origins of our traditional 
wisdom. 
The Moses of American plant ecol- 
ogy is Frederick E. Clements, who, 
at about the turn of the century, was 
the first naturalist to frame a com- 
prehensive and intricate theory of 
plant communities. Because he stud- 
ied the dynamics of vegetation and 
not the flora of a region, Clements 
considered himself an ecologist rather 
than a plant taxonomist, who identifies 
the species composition of plant com- 
munities. The study of vegetation is 
concerned with the behavior of the 
plant ensembles in a habitat, their bio- 
mass, relative abundances, and struc- 
tural relations. More than a listing 
of species, this approach tries to relate 
these characteristics of the whole com- 
munity to aspects of the physical en- 
vironment, such as precipitation, soil 
conditions, and growing season. 
Clements believed that the vegeta- 
tion in a region is a living entity, a su- 
perorganism, capable of progressive 
development, stable maturity, and re- 
production. During this period in the 
history of biology, organismic meta- 
phors were most attractive to scien- 
tists. Clements gave the name climax 
plant community to what he consid- 
ered the adult form of vegetation in a 
region, the primeval virgin landscape 
that existed before the coming of set- 
tlers with ax and plow. Climax com- 
munities, which in Clements’s view 
represented the highest development 
of vegetation, once covered vast tracts 
of continental land and were domi- 
nated in each region by a few charac- 
teristic species determined by climate. 
In New England, for instance, the clas- 
sical climax forest (which stretched, 
unbroken, from Nova Scotia to Wis- 
consin) was a mixture of ancient 
beeches, hemlocks, and sugar maples. 
Arrayed against these vegetational 
entities, Clements saw the forces of de- 
struction: tornadoes, landslides, fires, 
and humans. To cope with these as- 
saults, he argued, vegetation has 
evolved a mechanism of self-replica- 
tion, or repair, called succession. After 
a patch of vegetation is devastated. 
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