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- Spohr, Shelley M.
- Spokane Nursery.
- Spokane Seed Company.
- Spokes, Tracey
- Spolsky, Christina
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- Sponchiado, Jonas
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- Sponholtz, Pamela J.
- Sponsler, Olenus Lee, 1879-1953
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- Spoon, Don
- Spoon, Ronald L.
- Spooner, Alden Jermain, 1810-1881
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- Spooner, Brian M
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- Spooner, D M
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- Spooner, John Dewey, 1935-
- Spooner, Peter
- Spooner, W. C. (William Charles), 1809?-1885
- Spooner, William H.
- Spooner-Hart, Robert
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- Sporer, Eduard, 1841-1898
- Sporleder, A
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- Sporting Arms and Ammunition Manufacturers' Institute.
- Sportsman.
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- Spósito, Tereza Cristina
- Sposito, Tereza Cristina Souza
- Sposta, Joseph W.
- Spotila, James
- Spotorno, Ángel Enrique
- Spotorno, Paula
- Spotswood, Erica
- Spotte, S
- Spotte, Stephen
- Spottiswoode & Co.
- Spottiswoode & Co.,
- Spottiswoode, Andrew,
- Spottiswoode, Claire N
- Spottiswoode, William, 1825-1883
- Spotton, H. B. (Henry Byron), 1844-1933
- Spotts, Alice Marial
- Spousta, Martin
- Spoutz African Violet Greenhouses,
- Spoutz, Jennie, Mrs.,
- Sprackland, R G
- Sprackland, Robert G
- Sprackland, Robert George
- Sprackland, Teri
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- Sprague, A. J.
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- Sprague, Henry H.
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- Sprague, Isabelle Baird
- Sprague, Jason E
- Sprague, Lucian
- Sprague, Roderick, 1901-
- Sprague, T A
- Sprague, Thomas Archibald
- Sprague, Victor, 1908-
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- Spraker, Ted H.
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- Spratt, D M
- Spratt, Ethel Rose 1887-1970
- Spratt, G.
- Spratt, G., Mrs.
- Spratt, Nelson T
- Spratt, T. A. B. (Thomas Abel Brimage), 1811-1888
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- Spray, Ruth
- Spreadborough, William
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- Sprecher-Uebersax, E
- Sprecher-Uebersax, Eva
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- Spreier, Christine
- Sprengel, Anton, 1803-1851
- Sprengel, Christian Konrad, 1750-1816
- Sprengel, Christian Konrad.
- Sprengel, Kurt Polycarp Joachim, 1766-1833
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- Sprenger, Christine M
- Sprenkle, Janice M
- Sprent, Charles
- Sprent, J F A
- Spreyer, Mark F.
- Spribille, Toby
- Sprick, Peter
- Sprigg, Margaret
- Sprigg, R C
- Spriggs, Elizabeth
- Spring Brook Nursery.
- Spring City Nurseries.
- Spring Green Post No. 253.
- Spring Hill Nurseries,
- Spring Hill Nurseries.
- Spring Hill Nursery Company.
- Spring Rice, Cecil
- Spring Water Dahlia Farm.
- Spring, Anton Friedrich, 1814-1872
- Spring, James W., Jr.,
- Spring, Nigel
- Spring, Samuel N. (Samuel Newton), 1875-1952
- Springate, Neil D
- Springbrook Gardens,
- Springbrook Nursery (South Haven, Mich.)
- Springdale Nurseries.
- Springer & Hansen.
- Springer, Alan M.
- Springer, Everett P.
- Springer, Fitzroy.
- Springer, Frank, 1848-1927
- Springer, Jenny.
- Springer, John S
- Springer, John.
- Springer, Joseph Tucker
- Springer, L.,
- Springer, M A
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- Springer, Paul F
- Springer, Stewart
- Springer, T. L.
- Springer, V G
- Springer, Victor G
- Springer, Victor Gruschka, 1928-
- Springett, J A
- Springfield Floral Co.
- Springfield Greenhouses.
- Springfield Museum of Natural History (Springfield, Mass.)
- Springfield Museum of Natural History.
- Springfield Nurseries.
- Springfield Nursery and Fruit Farm Association.
- Springfield Plant and Seed Co.
- Springfield Seed Company.
- Springfield, H. W.
- Springfield, H. W.,
- Springfield, Rollo.
- Spring-Gardens (London)
- Springhill Dahlia Farm.
- Springhill Farm.
- Springsguth, Samuel,
- Springside Dahlia Gardens.
- Springthorpe, R T
- Springthorpe, Roger T
- Springtime Bulb Farms, Inc.,
- Springtime Garden.
- Springtime Gardens.
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- Sproul, William Cameron, 1870-
- Sproule, John.
- Sproull, Frederick A
- Sprouse, Peter
- Spruce, Richard, 1817-1893
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- Spruijt & Co.
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- Sprunger, Samuel
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- Sprunt, James, 1846-1924
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- Sprunt, Susan V
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- Spry, Alan
- Spry, Constance, 1886-1960
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- Spry, Henry H. 1804-1842
- Spry, Henry Harpur
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- Spry, W.
- Spry, W. J. J. (William James Joseph), 1906
- Spry, W.,
- Spuler, A
- Spuler, Anthony
- Spuler, Arnold
- Spuler, Arnold, 1869-
- Spungis, Voldemars
- Spunky Bottoms Restoration Symposium May 2003-
- Spurbeck, Donald W.
- Spurlin, Barton K.
- Spurlock, Beverly
- Spurnny, Johann,
- Spurr
- Spurr, Charles W.
- Spurr, D T
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- Spurr, Josiah Edward, 1870-1950
- Spurr, Nigel K.
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