429. 
430. 
431. 
432. 
433. 
434. 
435. 
436. 
437. 
438. 
439. 
440. 
1959b. A floristic study of a 
southern Illinois swampy area. Ohio J. Sci. 59: 
89-100. 
Moir, D. R. 1957. An occurrence of buried conif- 
erous wood in the Altamont Moraine in North 
Dakota. Proc. N. Dak. Acad. Sci. 11: 1-5. 
Moyer, J. F. 1953. Ecology of native prairie in 
Iowa. Ph.D. Thesis. lowa State Col., Ames. 110 p. 
Moyer, L.R. 1910. The prairie flora of south- 
western Minnesota. Bull. Minn. Acad. Sci. 4: 
357-378. 
Nelson, Jack R. 1961. Woody plant communities 
in the badlands of western North Dakota (Ab- 
stract). Proc. N. Dak. Acad. Sci. 15, 1961 
meeting. 
Nichols, J. T. 1961. Variations in vegetation and 
microclimate on north and south facing slopes in 
the mixed prairie near Hays, Kansas. M.S. Thesis. 
Ft. Hays, Kans., State Col: 
: 1969. Range improvement 
practices on deteriorated dense clay wheatgrass 
range in western South Dakota. S. Dak. Agr. Expt. 
Sta. Bull 552. 23 p. 
Nielson, Etlar L., and John B. Moyle. 1941. Forest 
invasion and succession on the basins of two cata- 
strophically drained iakes in northern Minnesota. 
Amer. Midl. Nat. 25: 564-579. 
Noll. W. C. 1939. Environment and physiological 
activities of winter wheat and prairie during ex- 
treme drought. Ecology 20: 479-506. 
Olsen, Jerry S. 1958. Rates of succession and soil 
changes on southern Lake Michigan sand dunes. 
Bot. Gaz. 119: 125-170. 
Orput, P. A., and J. T. Curtis. 1957. Soil micro- 
fungi in relation to the prairie continuum in 
Wisconsin. Ecology 38: 628-637. 
Otto, James H. 1938. Forest succession in the 
southern limits of Early Wisconsin glaciation as 
indicated by a pollen spectrum from Bacon 
Swamp, Marion County, Indiana. Butler Univ. Bot. 
18 
441. 
442. 
443. 
444, 
445. 
446. 
447. 
448. 
449. 
450. 
451. 
452. 
Studies 4: 93-116. 
Ovington, J.D., Dale Heitkamp, and Donald B. 
Lawrence. 1963. Comparative plant biomass and 
productivity of prairie, savanna, oakwood, and 
maize field ecosystems. Ecology 44: 52-63. 
Owensby, Clenton E., and Kling L. Anderson. 
1967. Yield responses to time of burning. J. Range 
Manet. 20: 12-16. 
ee i Robert’ M.,Hydes and Killing I 
Anderson. 1970. Effects of clipping and supple- 
mental nitrogen and water on loamy upland blue- 
stem range. J. Range Mangt. 23: 341-346. 
Paintin, R.D. 1929, The morphology and nature 
of a prairie in Cook County, Illinois. Trans. Il. 
Acad. Sci. 21: 152-175. 
Pammel, L.H. 1902. Preliminary notes on the 
flora of western Iowa, especially from the 
physiographical ecological standpoint. Proc. Iowa 
Acad. Sci. 9: 152-180. 
1905. A comparative study of 
the vegetation of swamp, clay, and sandstone areas 
in western Wisconsin, southeastern Minnesota, 
northeastern, central, and southeastern Iowa. Proc. 
Davenport Acad. Sci. 10: 32-126. 
—_ Ss 1909. Flora of Lowa: peat bogs. 
Iowa Geol. Survey Annu. Rpt. (19). 1908. p. 
735-778. 
Parker, D. 1936. Affinities of the flora of Indiana. 
Amer. Midl. Nat. 17: 700-724. 
Partch, M. L. 1949. Habitat studies of soil mois- 
ture in relation to plants and plant communities. 
Ph.D. Thesis. Univ. Wis., Madison. 
1962. Species distribution in a 
prairie in relation to water-holding capacity. Proc. 
Minn. Acad. Sci. 30: 38-43. 
Pase, Charles P. 1958. Herbage production and 
composition under immature ponderosa pine in 
the Black Hills. J. Range Mangt. 11: 238-243. 
Patel, K. R., F. W. Albertson, and G. W. Tomanek. 
1964. Micro-climate and vegetation responses on 
three big bluestem (Andropogon gerardi Vitman) 
