Epsilon Archive for Student Projects

Abstract

Stump treatment against Heterobasidion spp. root infection has not been commonly
conducted on Scots pine (Pinus sylvestris L.) plantations in Sweden. To assess whether
it should be, growth and volume losses caused by H. spp. was studied in a 36-year old
Scots pine stand in southern Sweden. A total of 24 Scots pine trees were extracted and
checked for H. spp. root infection, followed by a stem analysis reconstructing the
volume growth. Root morphology and location of infection were studied and different
above-ground indicators were tested to assess the incidence of infection. H. spp. were
detected on 87.5% of the studied trees and colonized 9.7% of root volume in average
(0.0-32.3%), which resulted in a growth reduction of 1.93 m3 per hectare in the latest
five years. Roots and infections were located unevenly in cardinal directions. Large
primary roots were most susceptible to infections. Needle retention, crown length,
DBH and presence of Heterobasidion fruiting bodies were not accurate enough as an
infection indicator. In conclusion, the root morphology and data of infection may be
used to calibrate some root disease models and it is recommended that stump treatment
on Scots pine is conducted to maintain the site productivity in southern Sweden.