Yazar
r c roark
16 cilt bulundu.
R. C. Roark · U.S. Dept. of Agriculture
11 sayfa · 1919
Pyrethrum (Insecticide) / Insecticides / Daisies
R. C. Roark · U.S. Dept. of Agriculture
88 sayfa · 1934
Bibliography / Chloropicrin / Fumigants / Insecticides
R. C. Roark · U.S. Dept. of Agriculture, Agricultural Research Service
33 sayfa · 1955
Insecticides / Allethrin
R. C. Roark · U.S. Dept. of Agriculture, Bureau of Entomology and Plant Quarantine, Division of Insecticide Investigations
133 sayfa · 1936
Insecticides / Plant pests / Plant health / Arthropod pests
R. C. Roark · U.S. Dept. of Agriculture
86 sayfa · 1932
Bibliography / Dalbergia / Insecticidal plants / Insecticides / Pesticides
E. B. White, Katharine Sergeant Angell White, Marjorie Kinnan Rawlings, Leonard Q. Ross, , · Tudor Publishing Company
R. C. Roark, United States. Bureau of Entomology and Plant Quarantine · The Bureau
90 sayfa · 1940
Insecticides / Patents / United States. Bureau of Entomology and Plant Quarantine. Division of Insecticide Investigations
R. C. Roark, United States. Bureau of Entomology and Plant Quarantine. Division of Insecticide Investigations · U. S. Dept. of Agriculture, Bureau of Entomology and Plant Quarantine, Division of Insecticide Investigations
174 sayfa · 1938
Insecticides / Botanical insecticides / Bibliography / Insecticidal plants
R. C. Roark, United States. Bureau of Entomology and Plant Quarantine. Division of Insecticide Investigations · U. S. Dept. of Agriculture, Bureau of Entomology and Plant Quarantine, Division of Insecticide Investigations
28 sayfa · 1938
Insecticides / Botanical insecticides / Bibliography / Derris