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Can. Ent. 115: 679-688 (1983) The parasite and predator component of within-tree southern pine beetle, Dendroctonus frontalis Zimmermann, mortality was investigated by mechanically excluding insect parasites and predators from the bark surface of naturally infested shortleaf, Pinus echinata Mill., and loblolly, P . taeda L., pines. Mortality caused by insect parasites and predators was determined by comparisons of five treatments that differed only in the duration of natural enemy exclusion. These natural enemies were responsible for 28.04% and 23.85% of the within-tree beetle mortality in 1978 in Arkansas and in 1979 in Georgia, respectively. Natural enemy species that arrived on the tree during the first week following mass attack by beetles caused the greatest amount of mortality.Predator density was greater than parasite density at both locations. The majority of the predator complex arrived during the first week following mass attack by beetles, while the parasite complex arrived throughout the entire period of beetle brood development.A linear response was found between the number of southern pine beetle prey and the number of prey destroyed per predator. A mean ( + S.E.) of 4.79 + 0.64 southern ~ -pine beetle immature~ were destroyed by each individual predator. Resume L'ClCment parasite-prCdateur de la mortalit6 intra-arbre chez le dendroctone mCridional du pin, Dendroctonus frontalis Zimrnermann, a kt6 CtudiC en excluant mkcaniquement les insectes parasites et prkdateurs de la surface de 1'Ccorce des pins Pinus echinata Mill., et P. taeda L. La mortalit6 causCe par les parasites et les pre-'dateurs a Ct C dCterminCe en comparant 5 traitements diffkrant seulement par la pCriode d'exclusion des ennemis naturels. Ceux-ci ont comptC pour 28.04% et 23.85% de la mortalit6 intra-arbre respectivement, en Arkansas en 1978, et en Georgie en 1979.Les especes d'ennemis naturels qui sont arrives sur l'arbre durant la premikre semaine suivant l'attaque massive du dendroctone ont causC la majeure partie de la mortalitk. La densite de prkdateurs Ctait plus ClevCe que la densit6 de parasites aux deux endroits. La majeure partie du complexe des predateurs sont arrivCs la premiere semaine suivant l'attaque massive du dendroctone, alors que le complexe des parasites sont amvCs pendant toute la pCriode de dCveloppement de la couvCe du dendroctone.Une relation linCaire a Ct C observCe entre les nombres du dendroctone prCsents 'et les nombres CliminCs par prkdation. Une moyenne ( k E.S.) de 4.79k0.64 individus immatures du dendroctone ont Ct C dCtruits par prkdateur.

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