Suomen paikallisissa lannoituskokeissa esiintyneiden huippusatojen jakautuneisuus eri leveyspiireille

Authors

• Onni Pohjakallio Helsingin yliopiston kasvipatologinen laitos

DOI: https://doi.org/10.23986/afsci.71321

Abstract

Examination of the experimental results of the local fertilizing experiments indicate that peak yields [the air-dry yields of the herbage plants, green fodder, and summer cereals (grains + straws) exceeding 10 000 kg, and the tuber yields of potatoes exceeding 40 000 kg per hectare] have appeared as far up as the most northern regions of Finland (Table 1, Maps I—4). These results support the opinion (11) that the light doses of the summer months proper in North Finland suffice to give about equally abundant photosynthetic production as in the south of the country. Even though the dose of light is smaller in Lapland than in the southern parts of the country (3) it is obvious that the light conditions in Lapland, too, do not prevent plant cultivation from being an economic proposition when the cultivation is limited to plants for which the period of growth is not too short. On the contrary, no special effect of the unbroken day, which would suffice to compensate the shortness of the period of growth, has been established from the appearance of the peak yields at the different latitudes in Finland.