Canadian Forest Service Publications
Flushing black and white spruce flowers as an aid in predicting cone crops. 1982. Haavisto, V.F.; Gordon, A.G. Canadian Forestry Service, Forest Pest Management Institute, Sault Ste. Marie, Ontario, Ontario Ministry of Natural Resources, Sault Ste. Marie, Ontario.
Available from: Great Lakes Forestry Centre
Catalog ID: 9314