Published online by Cambridge University Press: 31 May 2012
The seasonal development of N. swainei was recorded in northwestern Quebec for six consecutive years from 1956 to 1961. Larvae normally spun cocoons during September when temperatures were usually below the optimum for survival. An earlier and more favourable spinning period depended principally upon an early adult emergence which, in turn, was governed by prevailing temperatures, the degree of shading of the humus, the presence of encapsulated tachinid parasites, the prior period spent in prolonged diapause, and the geographic origin of the specimens. It was concluded that early emergence of adults followed by rapid development of the immature stages for successive years are prerequisites for epidemics of N. swainei in northwestern Quebec, and are unlikely in very dense jackpine stands.
To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Dropbox account. Find out more about saving content to Dropbox.
To save this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Google Drive account. Find out more about saving content to Google Drive.