24 



III. LITERATURE CITED 



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Cronquist, A. 1955. Vascular plants of the Pacific Northwest. 

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Cronquist, A. 1991. Letter to Lisa A. Schassberger, Montana 

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Dorn, R.D. 1984. Vascular plants of Montana. Mountain West 

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Gorman, J.D. 1987. Letter to G. Ownbey, University of 

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Hitchcock, C.L. and A. Cronquist. 1973. Flora of the Pacific 

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Louda, S.M., M.A. Potvin and S.K. Collinge. 1990. Predispersal 

 seed predation, postdispersal seed predation and competition 

 in the recruitment of seedlings of a native thistle in 

 sandhills prairie. American Midland Naturalist 124: 105- 

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Massey, J.R., and P.D. Whitson. 1980. Species biology, the key 

 to plant preservation. Rhodora 82:97-103. 



Mathews, S. 1990. Cirsium longistylum project: summary report. 

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Montagne, C. , L.C. Munn, G.A. Nielsen, J.W. Rogers and H.E. 

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Moore, R.J. and C. Frankton. 1963. Cytotaxonomic notes on some 

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Ownbey, G.B. 1987. Letter to J.D. Gorman, Lewis and Clark 

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Ownbey, G.B. 1990. Letter to L.A. Schassberger, Montana Natural 

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Rees, N.E. 1982. Collecting, handling and releasing Rhinocyllus 

 conicus, a biological control agent of musk thistle. U.S. 

 Department of Agriculture, Agriculture Handbook 579. 7 pp. 



