Canadian Forest Service Publications
Hemlock looper egg hatching: regular as clockwork. 2010. Delisle, J. Natural Resources Canada, Canadian Forest Service, Laurentian Forestry Centre, Quebec, QC. Branching out No. 57. 2 p.
Available from: Laurentian Forestry Centre
Catalog ID: 31713
Series: Branching Out (LFC - Québec)
In late summer, the female hemlock looper lays her eggs singly on tree trunks and branches, where they overwinter before hatching the following spring. Researchers with the Canadian Forest Service and Université Laval have been able to explain the synchronized hatching of the eggs of this insect species by studying its embryonic diapause, which consists of three phases: prediapause, diapause and postdiapause. The external factors governing the duration of each of the three phases have been studied in order to develop a model to predict egg hatching, an essential tool for the integrated management of this major pest of balsam fir in eastern Canada.
Also available under the title:
Réglée comme une horloge : l'éclosion des oeufs de l'arpenteuse de la pruche. L’éclaircie du Service canadien des forêts, Centre de foresterie des Laurentides. No. 57. (French)