Journal of Entomological Science (2002) 37, 259-269

James D. Dutcher (2002)
Insect damage estimates for 'Stuart' pecan nutlets from nut set to shell hardening in insecticide-treated and untreated trees
Journal of Entomological Science 37 (3), 259-269
Abstract: Pecan nut loss due to pecan nut casebearer, Acrobasis nuxvorella Neunzig, damage was significantly lower in the chlorpyrifos-treated, 'Stuart', pecan trees (0%) than in untreated trees (16%). Percentage loss due to nut drop from all causes between nut set and shell-hardening was significantly lower in the treated (27%) than in the untreated trees (42%). Treated trees had significantly higher average yield (38 kg/tree) than the untreated (29 kg/tree). Nut size was significantly smaller in untreated (156 nuts/kg) than in treated trees (145 nuts/kg). Monitoring the fate of 'Stuart' pecan nutlets from nut set to harvest indicated that the number of nuts/cluster at nut set was often positively correlated with kernel weight at harvest, whereas, nut cluster size later in the season was positively correlated with kernel weight at two orchards and negatively correlated with kernel weight in the control treatment at a third orchard. A commercial orchard where pecan nut casebearer, hickory shuckworm, Cydia caryana (Pitch) and nut curculio, Conatrachelus hicoriae Schoof, were controlled with insecticide sprays in the spring had similar total nut drop over the entire season as an orchard where these insects were not controlled. The majority of the pecans that dropped from the trees did not have discernible signs of plant disease, insect, feeding damage or insect oviposition.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): James D. Dutcher

Research topic(s) for pests/diseases/weeds:
damage/losses/economics
control - general

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Acrobasis nuxvorella	Pecan/hickory (Carya)	U.S.A. (SE)
	Cydia caryana	Pecan/hickory (Carya)	U.S.A. (SE)
	Conotrachelus hicoriae	Pecan/hickory (Carya)	U.S.A. (SE)