Super-, thomas- ja hienofosfaatin vaikutuksesta mutasuolla

Authors

• Mauri Takala Suoviljelysyhdistys, Leteensuon koeasema

DOI: https://doi.org/10.23986/afsci.71564

Abstract

At Leteensuo Experiment Station a test to compare the effects of superphosphate and basic slag on fen soil was started in 1930. The peat on the test area is fairly well humified forest sedge peat. The thickness of the peat layer is more than 1 metre. The test area was reclaimed in 1928 and ditched so that the strips between ditches are 20 metres broad. The test area was clayed in 1930 (100 m3/ha) and in 1942 (200 m3/ha). The test areas which were limed were treated with slaked lime (2000 kg/ha) in 1930 and with limestone powder (2000 kg/ha) in 1937. Basic slag was applied in amounts containing citric acid soluble P2O5 as much as superphosphate contained ammonium citrate soluble P2O5. In 1948 when the test area was 3rd year ley the trial plan was changed so that basic slag was replaced by the corresponding amount of hyperphosphate. In 1941 no phosphate dressing was applied, and potassium dressing was only 60 kg/ha K2O. From the years 1943 and 1944 no test results are available. According to the test results the effect of superphosphate and basic slag are equal in cultivating cereals. As cover dressing for ley superphosphate is more suitable than basic slag or hyperphosphate. By means of appropriate cover dressing with phosphate and potassium it is possible to lenghten the age of timothy ley without impairment of crop quantity or quality. While the age of timothy ley lengthens, weeds, especially quick grass, may appear.