Effect of defoliation by Thaumetopoea pityocampa (Den. & Schiff.) (Lepidoptera: Thaumetopoeidae) on annual diameter increment of Pinus brutia Ten. in Turkey

Abstract

-In this study, the influence of defoliation by pine processionary moth, Thaumetopoea pityocampa (Den. & Schiff.) (Lepidoptera: Thaumetopoeidae) on the annual diameter increment of Turkish Calabrian pine, Pinus brutia Ten. in Kahramanmaras province, Turkey, was investigated. The study was carried out between 1995 and 1998. During the four years, the defoliation of pine processionary moth caused a significant decrease (average 21% for four years, P < 0.05) in the annual diameter increment with respect to control, undefoliated trees. Thaumetopoea pityocampa / diameter increment / Kahramanmaras / Turkey / Pinus brutia Résumé -Effet des défeuillaisons par Thaumetopoea pityocampa (Den. & Schiff.) sur l'accroissement annuel de Pinus brutia Ten. enTurquie. L'influence de défeuillaisons par la processionnaire du Pin Thaumetopoea pityocampa, sur l'accroissement annuel en diamètre de Pinus brutia, a été testée dans la province de Kahramanmaras, en Turquie. L'étude fut conduite de 1995 à 1998. Durant ces 4 années, les défeuillaisons ont causé une diminution significative (en moyenne 21 % pour les 4 ans, P < 0,05) de l'accroissement annuel en diamètre, en comparaison avec des témoins non défeuillés.Thaumetopoea pityocampa / accroissement en diamètre / Kahramanmaras / Turquie / Pinus brutia

Effects of defoliation by the pine processionary moth Thaumetopoea pityocampa on biomass growth of young stands of Pinus pinaster in northern Portugal

“…In spite of the capability of defoliated trees to refoliate and survive, the effects of defoliation are very significant (Fratian 1973) with losses in volume, radial growth (Carus 2004, Kanat et al 2005, Laurent-Hervouet 1986 and biomass pro duction (Markalas 1998). Kanat et al 2005 reported a significant decrease (average 21% over four years) on annual diameter incre ment of Pinus brutia in Turkey while Carus (2004) identified growth reductions on radial height and volume on P. brutia after an out break of T. pityocampa. Cadahia & Insua (1970) identified a decrease in wood volume increment of 14-33% in young P. radiata as well as losses in tree volume, while Bouchon & Toth (1971) reported that T. pityocampa attack was responsible for an about 45% volume decrease over a 50 year period.…”

“…Defoliation removes both photosynthetic material and sites where chemicals such as growth hormones are pro duced, affecting many vital functions (Carus 2004). It is well known that in adult trees de foliation, though repeated over consecutive years, seldom causes death (Ruperez 1956, Kailadis 1962), but increases susceptibility to sanitary problems such as pine weevils and bark beetle attack (Kanat et al 2005, Markalas 1998). In spite of the capability of defoliated trees to refoliate and survive, the effects of defoliation are very significant (Fratian 1973) with losses in volume, radial growth (Carus 2004, Kanat et al 2005, Laurent-Hervouet 1986 and biomass pro duction (Markalas 1998).…”

“…It is well known that in adult trees de foliation, though repeated over consecutive years, seldom causes death (Ruperez 1956, Kailadis 1962), but increases susceptibility to sanitary problems such as pine weevils and bark beetle attack (Kanat et al 2005, Markalas 1998). In spite of the capability of defoliated trees to refoliate and survive, the effects of defoliation are very significant (Fratian 1973) with losses in volume, radial growth (Carus 2004, Kanat et al 2005, Laurent-Hervouet 1986 and biomass pro duction (Markalas 1998). Kanat et al 2005 reported a significant decrease (average 21% over four years) on annual diameter incre ment of Pinus brutia in Turkey while Carus (2004) identified growth reductions on radial height and volume on P. brutia after an out break of T. pityocampa.…”

“…-Lep., Thaumetopoeidae) is one of the most de structive insects of Pinus and Cedrus in the Middle East, North Africa and many south ern European countries, including Portugal. The urticant hairs of the late instar larvae provokes serious reactions in humans and other mammals (Lamy 1990, Oliveira et al 2003 but it is also responsible for significant economic damage due to severe defoliation (Buxton 1983, Devkota & Schmidt 1990, Kanat et al 2005. Defoliation removes both photosynthetic material and sites where chemicals such as growth hormones are pro duced, affecting many vital functions (Carus 2004).…”

“…-Lep., Thaumetopoeidae) is one of the most de structive insects of Pinus and Cedrus in the Middle East, North Africa and many south ern European countries, including Portugal. The urticant hairs of the late instar larvae provokes serious reactions in humans and other mammals (Lamy 1990, Oliveira et al 2003 but it is also responsible for significant economic damage due to severe defoliation (Buxton 1983, Devkota & Schmidt 1990, Kanat et al 2005 (1971) reported that T. pityocampa attack was responsible for an about 45% volume decrease over a 50 year period.The effect of insect action on trees can be studied using predictive models (Hogg 1999) which allow estimates of dendrometric va riables (e.g., height, volume, and biomass) and can be used for inventory techniques in production studies (Komiyama et al 2008, Sochackia et al 2007). However, the use of allometric models to estimate the impact of insects on forest dynamics is virtually un known.…”