AMERICAN 
JOURNAL OF BOTANY 
Vol. VI March, 1919 No. 3 
THE ECOLOGIC SUBTERRANEAN ANATOMY OF SOME 
PLANTS OF A PRAIRIE PROVINCE IN CENTRAL 
IOWA 
Ada Hayden 
Introduction 
A survey of the literature pertaining to functional and adaptational 
features of subterranean organs as related to their morphology shows this 
subject to have been less investigated than that of leaf structure. Though 
there has been considerable work done in the field of pure morphology, 
that too is yet deficient in many respects. Descriptions found in Gray's 
Manual of Botany (8) and Britton and Brown's Flora (i) have either no 
reference to subterranean parts or only incomplete ones. 
The subterranean organs of prairie plants are of two classes, roots and 
subterranean stems. Of course all these plants have secondary, i. e., ab- 
sorbent or collecting roots, but in many plants the subterranean stems are 
intermediate structures connecting collecting roots with conducting aerial 
stems and therefore assume the function of primary or main roots. 
Prominent subterranean stems are seen in the majority of alluvial basin 
plants and in modified abbreviated form in the upland plants, especially in 
the grasses and composites which constitute the majority of the upland 
plants. 
It was the object of this study of subterranean stem and root types (a) 
to note whether variations were correlated with habitat; (b) to determine 
whether the stems were equivalent to or advantageous to the root in the 
economy of the plant. 
The functions of subterranean organs are storage, anchorage, absorption, 
conduction, and propagation. Anchorage in the case of prairie plants may 
be dismissed, for most of them are low, have a compact habit of growth, 
and are not particularly subject to uprooting. As to propagation, the fact 
that subterranean stems have numerous nodal buds while roots have ad- 
ventitious buds, if any, gives subterranean stems, especially rhizomes, the 
advantage as propagators. Concerning storage, the root and the subterra- 
nean stem seem to be equally well equipped, though this question will be 
discussed under anatomical structure. 
[The Journal for February (6: 47-86) was issued March i, 19 19.] 
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