ECOLOGY. 303 



ECOLOGY. 



Clements, F. E., Tucson, Arizona. Associate in Ecology. 



The field season of 1917 has been devoted to several of the larger 

 problems in synthetic ecology. It was intended to spend the summer 

 in completing the inquiry into the relation between present and past 

 climatic cycles and the succession of plant and animal communities in 

 Bad Lands, but in pursuance of the action of the Executive Committee 

 of the Institution, it was decided to give the chief attention to grazing 

 problems, expecially those deaUng with carrying capacity and the con- 

 sequences of overgrazing; this choice proved doubly opportune, owing 

 to the drought prevalent throughout the grazing regions of the West and 

 the critical situation arising out of the grazing homestead act. Fur- 

 thermore, the general distribution of the open range agrees closely with 

 that of Bad Lands, with the result that the work on the latter has been 

 practically completed. While the lines of research are intimately 

 correlated, they center upon five main problems, namely: (1) grazing, 

 (2) indicator plants, (3) climatic cycles, (4) Bad Lands, (5) permanent 

 quadrats. 



Grazing Research. 



Grazing conditions have been studied in northern Arizona, New 

 Mexico, Colorado, northern Utah, Wyoming, northwestern Nebraska, 

 western North Dakota, Montana, Oregon, and California. The major 

 part of the work has been done on the open range and on private 

 ranches, but considerable time has also been spent on the ranges of the 

 National Forests. Particular attention has again been paid to the 

 ecological studies carried on at the Utah Grazing Experiment Station, 

 the Jornada Grazing Reserve, and the Santa Rita Grazing Reserve of 

 the Forest Service, and at the Mandan Station of the Bureau of Plant 

 Industry of the U. S. Department of Agriculture. A close scrutiny 

 of the situation makes it clear that the grazing industry is in a criti- 

 cal condition throughout the entire West and that immediate action 

 in accordance mth the scientific results is imperative. It has proved 

 possible to construct a new and practical system based upon the 

 intensive quadrat studies of the several reserves and the extensive 

 investigations of the summer. This rests upon five cardinal points, 

 namely: (1) classification, (2) protection, (3) utilization, (4) plant intro- 

 duction, (5) cooperation; it will be treated in detail in the monograph 

 on indicator plants and vegetation. 



Indicator Plants. 



The recognition and use of plants and plant communities as indica- 

 tors constitute an outstanding problem in synthetic ecology which has 

 been almost wholly neglected. It is based upon the fundamental fact 



