1987 census of agriculture. Volume 1, Geographic area series - United States. Bureau of the Census. (For sale by Supt. of Docs., U.S. G.P.O, 1989)

1997 IUCN red list of threatened plants (1997)

20th anniversary seed catalogue, 1940 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Rocky Mountain Seed Company, 1940)

22nd annual seed catalogue - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Reichardt & Schulte Co., Inc, 1921)

23rd annual seed catalogue of the Reichardt & Schulte Co., Inc. : farm, garden and flower seeds - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Reichardt & Schulte Co., Inc, 1922)

25th anniversary catalogue : 1931 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Kallay Bros. Company, 1931)

25th Anniversary seed annual, 1921-1946 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Braeger's Oregon Seed Store, 1946)

25th annual seed catalogue - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alexander Drug and Seed Co, 1898)

26th Annual catalogue and pricelist of seeds - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (The Company, 1899)

26th seed annual, 1946 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Grand Rapids Growers Inc, 1946)

29th Annual catalogue and pricelist - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (The Company, 1902)

32d annual spring catalogue - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alexander Seed Co, 1905)

33rd annual spring catalogue. 1906 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alexander Seed Co, 1906)

34th anniversary sale : established 1895 1929, 1/3 of a century [catalog] - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Berry Seed Co, 1929)

34th annual spring catalogue : highest 1907 quality - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alexander Seed Co, 1907)

35th anniversary sale : mid-season cut price - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Berry Seed Co, 1930)

35th annual spring catalogue : highest 1908 quality - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alexander Seed Co, 1908)

36th annual catalog : what to plant how to plant when to plant - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Otto Schwill & Company, 1905)

40th year : Jefferson brand - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Jefferson Seed Houses, 1924)

46th annual catalog, 1931 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Tillinghast Seed Company, 1931)

'48 garden annual : Ted's Feed & Seed Store - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Monarch Seed & Feed Co, 1948)

49th annual catalog of celebrated O.K. seeds : 1932 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Everitt's Seed Stores, 1932)

49th summer and fall catalogue and price list : high grade seeds ready for distribution - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (J. Steckler Seed Co., Ltd, 1914)

500 wild flowers of San Antonio and vicinity - Quillin, Ellen Schulz, 1892 -1970 (The author, 1922)

50,000 farmers save 1/3 to 1/2 cost : alfalfa, clover, corn, fescue ... : money-back guarantee - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Standard Seed Company, 1935)

50th anniversary : 1905-1955 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Fraziers Seed Store, 1955)

50th anniversary : 1940 year book - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (State Nursery & Seed Co, 1940)

50th annual catalogue. seeds, bulbs, hardware and farm supplies. 1919 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (F.H. Ebeling, 1919)

50th annual seed and plant catalogue, 1933 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Bros, 1933)

50th year 1897 1947 seed annual - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Stumpp & Walter Co, 1947)

51 years of satisfactory seed service : 1896-1947, grow delicious vegetables from your own garden, for health, pleasure and economy - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Springfield Seed Co, 1947)

51st anniversary : 1941 year book - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (State Nursery & Seed Co, 1941)

51st annual catalog, 1883-1934 : Pioneer Seed House Nursery & Greenhouses of the Northwest - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oscar H. Will & Co, 1934)

51st annual catalogue and garden manual for the Southern states of the J. Steckler Seed Co., Ltd. : 1917 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (J. Steckler Seed Co., Ltd, 1917)

51st annual seed and plant catalogue, 1934 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Bros, 1934)

51st summer and fall catalogue and price list [of] high grade seeds ready for distribution : new crop, 1916 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (J. Steckler Seed Co, 1916)

52 years of satisfactory seed service : Springfield Seed Company 1896-1948 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Springfield Seed Co, 1948)

52nd anniversary : 1942 year book - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (State Nursery & Seed Co, 1942)

52nd annual seed and plant catalogue, 1935 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Bros, 1935)

52nd summer and fall catalogue and price list : high grade seeds - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Steckler, 1917)

53rd annual catalogue [of] seeds, hardware, implements - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (F.H. Ebeling, 1921)

53rd annual seed and plant catalog, 1936 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Bros, 1936)

54th annual catalog, 1883-1937 : Pioneer Seed House Nursery & Greenhouses of the Northwest - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oscar H. Will & Co, 1937)

55th Annual catalog, 1883-1938 : Pioneer Seed House Nursery & Greenhouses of the Northwest - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oscar H. Will & Co, 1938)

55th annual seed and plant catalog, 1938 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Bros, 1938)

56th annual catalog, 1883-1939 : Pioneer Seed House Nursery & Greenhouses of the Northwest - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oscar H. Will & Co, 1939)

56th annual catalogue [of] seeds, hardware, implements, poultry supplies, dog foods - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (F.H. Ebeling, 1924)

56th annual seed and plant catalog, 1939 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Bros, 1939)

57th annual catalog, 1883-1940 : Pioneer Seed House Nursery & Greenhouses of the Northwest - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oscar H. Will & Co, 1940)

57th annual catalog, 1942 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Tillinghast Seed Company, 1942)

57th annual catalogue and garden manual for the southern states of the J. Steckler Seed Co., Ltd - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Steckler, 1923)

57th annual seed and plant catalog, 1940 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Bros, 1940)

58 years of satisfactory seed service - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Springfield Seed Company, 1954)

58th annual catalogue and garden manual for the southern states of the J. Steckler Seed Co., Ltd - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Steckler, 1924)

58th annual catalogue [of] seeds, hardware, implements, poultry and bird supplies, dog foods - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (F.H. Ebeling, 1926)

58th annual seed and plant catalog, 1941 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Brothers, 1941)

59 years of satisfactory seed service since 1896 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Springfield Seed Company, 1955)

59th annual catalog, 1883-1942 : Pioneer Seed House Nursery & Greenhouses of the Northwest - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oscar H. Will & Co, 1942)

59th annual seed and plant catalog, 1942 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Brothers, 1942)

600 acres of everything that's good and hardy, 1929 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Cole Nursery Company, 1929)

60th annual catalog, 1943 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Brothers, 1943)

60th annual catalog ; Skagit brand seed - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Tillinghast Seed Company, 1945)

61st annual catalog, 1883-1944 : Pioneer Seedhouse Nursery & Greenhouses of the Northwest - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oscar H. Will & Co, 1944)

61st annual catalog, 1944 : complete victory garden - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Brothers, 1944)

61st catalog, 1946 ; Skagit brand seed - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Tillinghast Seed Company, 1946)

62nd annual catalog, 1883-1945 : Pioneer Seedhouse Nursery & Greenhouses of the Northwest - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oscar H. Will & Co, 1945)

62nd annual catalog, 1945 : complete victory garden - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Brothers, 1945)

63rd annual catalog, 1883-1946 : Pioneer Seedhouse Nursery & Greenhouses of the Northwest - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oscar H. Will & Co, 1946)

63rd year, 1946 : victory garden collection - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Alneer Brothers, 1946)

64th catalog, 1949 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Tillinghast Seed Company, 1949)

65th annual catalog, 1883-1947 : Pioneer Seedhouse Nursery & Greenhouses of the Northwest - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oscar H. Will & Co, 1947)

65th annual catalog, 1883-1948 : Pioneer Seedhouse Nursery & Greenhouses of the Northwest - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oscar H. Will & Co, 1948)

65th catalog, 1950 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Tillinghast Seed Company, 1950)

66th annual catalog, 1883-1949 : Pioneer Seedhouse Nursery & Greenhouses of the Northwest - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oscar H. Will & Co, 1949)

66th catalog, 1951 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Tillinghast Seed Co, 1951)