Open AccessAreal distribution of a Neodiprion sertifer (Hym., Diprionidae) outbreak on Scots pine as related to stand condition
Author(s) -
Larsson Stig,
Tenow Olle
Publication year - 1984
Publication title -
ecography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.973
H-Index - 128
eISSN - 1600-0587
pISSN - 0906-7590
DOI - 10.1111/j.1600-0587.1984.tb01108.x
Subject(s) - sawfly , outbreak , scots pine , larva , biology , ecology , abundance (ecology) , forestry , pinus <genus> , geography , botany , virology
Analyses of a recent N. sertifer outbreak in southern Sweden were made during on‐going attack, comprising a regional and local mapping of defoliation severity, as well as a study of intensity of larval consumption, abundance of cocoons and parasitation of larvae in relation to fertilizer application. It was found that (1) the outbreak was preceded by summer and autumn droughts, (2) it was limited to infertile soils, (3) pine stands aged 20–40 yr suffered most, (4) it was less severe in trees benefiting from a reduced inter‐tree competition, as measured from tree‐ring growth, and (5) less severe in a fertilized stand. The findings support the hypothesis on a fundamental effect of stand nutritive state on changes in number of the sawfly.