Fertilization practice in Finnish forest nurseries from the standpoint ofenvironmental impact

摘要

In 1996 a questionnaire concerning actual systems and practices used in production of seedlings was sent to 33 Finnish forest nurseries. A total of 28 nurseries answered the questionnaire. These replies represented about 80% of the total production of forest seedlings in Finland. The nurseries used about 200 metric tons of fertilizers in 1996, which was about 25% of the fertilizer use in 1976. Explanations for the decrease in fertilization are the shift from bareroot production to container production and the decrease in total production from 190 to 150 million seedlings. Finnish nurseries applied about 100 mg N and 50 mg P per container seedling shipped, and 820 mg N and 240 mg P per bareroot seedling. The mean annual applications of N and P in 1996 were about 180 kg/ha and 90 kg/ha for container stock and 130 kg N/ha and 40 kg P/ha for bareroot stock. However, the variation between nurseries was large.