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Sorghum production in Kansas
1933
Laude, H. H. | Swanson, Arthur F.
Accidentes agentes enemigos y enfermedades de las principales hortalizas cultivadas
1933
Valdés S., Francisco
"Todas las plantas tienen sociedad con el agua, pero las exigencias de cada planta, respecto a este elemento es muy variable"
显示更多 [+] 显示较少 [-]Alfalfa común, (Medicago sativa)
1933
Martínez Valadez, Carlos
"Cree que su origen sea media, de donde toma su nombre en la antigua Grecia y por tanto Italia"
显示更多 [+] 显示较少 [-]De economische beteekenis van het bosch voor Nederland
1933
Sprangers, A.A.C.
The history of forests in the Netherlands was described. In more recent times Dutch forests supplied a modest but interesting portion of Dutch timber. They supplied all agricultural timber, stakes and poles for horticultural and agricultural crops, almost all firewood, a third of the pit props and most of the wood for protecting stream banks. Poles had many uses. The wood of the Canadian poplars satisfied the whole need for clog making and for matches, and there was a surplus for export. Secondary uses were important: tannins, bilberries, tree seeds and hunting rents.The forests also attracted tourists and were thus of aesthetic and economic value.Despite the replacement of forest by agriculture the forest area was being increased by the afforestation of waste lands. The reclamation of waste lands principally for afforestation needed active promotion, although cost had to be considered. Management had to be based on production. Grading and volume measurement of felled timber, culture of Canadian poplar, and the sale of different timbers needed more attention.
显示更多 [+] 显示较少 [-]De economische beteekenis van het bosch voor Nederland
1933
Sprangers, A.A.C.
The history of forests in the Netherlands was described. In more recent times Dutch forests supplied a modest but interesting portion of Dutch timber. They supplied all agricultural timber, stakes and poles for horticultural and agricultural crops, almost all firewood, a third of the pit props and most of the wood for protecting stream banks. Poles had many uses. The wood of the Canadian poplars satisfied the whole need for clog making and for matches, and there was a surplus for export. Secondary uses were important: tannins, bilberries, tree seeds and hunting rents.The forests also attracted tourists and were thus of aesthetic and economic value.Despite the replacement of forest by agriculture the forest area was being increased by the afforestation of waste lands. The reclamation of waste lands principally for afforestation needed active promotion, although cost had to be considered. Management had to be based on production. Grading and volume measurement of felled timber, culture of Canadian poplar, and the sale of different timbers needed more attention.
显示更多 [+] 显示较少 [-]Roughage production in New Hampshire
1933
Abell, Max F. (Max Flavel)
Farm Production Costs in Oklahoma, 1931
1933
Stephens, Philip Holcomb
Wheat production in Colorado, 1926-1932
1933
Robertson, D. W. (David Wield)
Barley production in North Dakota
1933
Stoa, T. E. (Theodore Ellinson)
Winter wheat production in South Dakota
1933
Klages, K. H. W.