By Chapman, Frank M. (Frank Michler), 1864-1945 . Genre Birds / Peru . Names peru / mus / urubamba / life / rio and 3569 more

By Jensen, Charles A. . Genre Nitrification . Names soil / wheat / bacteria / plants / roots and 541 more

By Richards, Edgar. . Genre Soils / Analysis . Names soil / ammonia / organic matter / plants / io and 448 more

By Kemptom, James Howard, 1891- . Genre Corn / Abnormalities / Inflorescences . Names seeds / flowers / flower / zea / plants and 253 more

Genre Lumber trade / Philippines / Forests and forestry / Philippines . Names wood / type / area / unidentified species / unidentified and 1223 more

By Berry, Wilton Guernsey. . Genre Food adulteration and inspection . Names wood / ammonia / victoria / fruit / bacteria and 477 more

Genre Chemistry, Analytic . Names beaker / sulphur / plants / ammonia / soil and 98 more

Genre Formaldehyde . Names data / sulphur / ix / bacteria / none and 131 more

By Bonsteel, Jay Allan, 1873- . Genre Soils / United States . Names soil / type / areas / virginia / organic matter and 117 more

By Gardner, Frank D. (Frank Duane), 1864-1963 . Genre Soils / Maryland . Names soil / plants / wheat / organic matter / type and 97 more