Sammanfattning

Fertilization and scarification are both performed to increase tree production at different stages of forest rotation periods. In this study, the effects of previous nitrogen fertilizations and scarification after clear felling on planted Pinus sylvestris L. seedlings and ground vegetation were investigated. Two fertilization experiments established around 1980 were harvested in 2006, after which the plots were scarified by disc trenching and re-planted. The plots had been repeatedly fertilized over a 20-year period before harvesting, with total N doses of 0, 450, 900 or 1800 kg N ha(-1). After five growing seasons, the growth, survival and nutrient contents of the seedlings were measured, and ground vegetation was collected to estimate its biomass and nutrient content. Pre-harvest fertilization alone had only minor effects on the results, but scarification increased both the survival and growth of the planted seedlings. However, without scarification, seedling mortality increased with increasing fertilization intensity. The ground vegetation biomass was higher in plots without scarification, but the total biomass of seedlings and ground vegetation was similar in all treatments. Scarification thus favored seedling growth at the expense of ground vegetation. Only a few effects on nutrient content were found, but there were no signs of nutrient imbalance in any of the treatments. At higher levels of fertilization, the K: N ratio in the seedlings decreased while the K content in the ground vegetation increased. Overall, scarification had a greater impact than pre-harvest fertilization on the planted seedlings and the ground vegetation.

Nyckelord

carryover; competing vegetation; disc trenching; establishment; nitrogen; regeneration; Scots pine

Publicerad i

Silva Fennica
2013, Volym: 47, nummer: 4
Utgivare: FINNISH SOC FOREST SCIENCEFINNISH FOREST RESEARCH

SLU författare

• Hjelm, Karin

  • Institutionen för sydsvensk skogsvetenskap, Sveriges lantbruksuniversitet
    
  • Skogforsk

Associerade SLU-program

SLU Future Forests


UKÄ forskningsämne

Skogsvetenskap


Publikationens identifierare

DOI: https://doi.org/10.14214/sf.1016

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/55188