Pine weevil Pissodes nemorensis: threat to South African pine plantations and options for control.

Pissodes nemorensis Germar (Coleoptera: Curculionidae) is native to North America, where it causes significant damage to young trees of various Pinus species. In North America, it can be associated with the pitch canker pathogen, Fusarium circinatum, that kills young trees and causes cankers on established trees. Pissodes nemorensis was first detected in South Africa in 1942 and has since been responsible for significant damage to local pine plantations. In South Africa, P. nemorensis is present throughout all pine-growing areas, and is often associated with trees that are stressed by factors such as hail damage and poor species-site matching. It also causes primary damage, by killing growing shoots of pines, resulting in forking or branching of tree leaders. With the recent appearance of the pitch canker fungus in South African nurseries, there is much concern that P. nemorensis will become associated with this pathogen here. The management of R nemorensis is essential to avoid losses to South African pines, but has received little attention. We review the available information on the biology, phenology, host preference, and damage potential of P. nemorensis. Other economically important species of Pissodes are considered where relevant. We also refer to our observations of the pest in the field and laboratory in South Africa, and present the options for the management of P. nemorensis under South African conditions and priorities for future research. [ABSTRACT FROM AUTHOR]