Agricultural and Forest Entomology (1999) 1, 27-31

M.J. Way, M.R. Paiva and M.E. Cammell (1999)
Natural biological control of the pine processionary moth Thaumetopoea pityocampa (Den. and Schiff.) by the Argentine ant Linepithema humile (Mayr) in Portugal
Agricultural and Forest Entomology 1 (1), 27-31
Abstract: 1 Defoliation by larvae of the pine processionary moth, Thaumetopoea pityocampa, is negligible in stands of Pinus pinaster colonized by the Argentine ant Linepithema humile which preys fiercely on the young moth larvae. In contrast, such damage is widespread where pine plantations are colonized by native ants, predominantly Tapinoma nigerrimum and Lasius niger, which seemingly disregard the larvae.
2 Where L. humile- and native ant-occupied sectors adjoin, there is a 20–50 m overlap in the transition area between L. humile- and native ant-occupied pines. This was most evident in a > 500 ha plantation where there was severe or very severe T. pityocampa attack in native ant sectors contrasting with none in adjoining L. humile sectors.
3 Predation by L. humile is no doubt enhanced by its existence as super-colonies over very large areas, by its foraging activity and recruitment on trees throughout the time when T. pityocampa and other prey are present, and by honeydew- producing Homoptera which help retain foraging L. humile workers in pine tree crowns.
4 The role of L. humile could be enhanced by cultivations that disturb the soil and restrain ground vegetation.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Maria Rosa Paiva

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution
environment/habitat manipulation

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Thaumetopoea pityocampa	Pine (Pinus)	Portugal (continental)
Linepithema humile (predator)	Thaumetopoea pityocampa	Pine (Pinus)	Portugal (continental)