Publication Title: 
Mercier et al. (1993)
Title: 
Relationships between Epilobium angustifolium phenology and Picea glauca seed maturation
Authors: 
Mercier Stephan, Langlois Charles-gilles
Publication Year: 
1993
Series Name: 
Forest Ecology and Management
Abstract: 
In an attempt to identify whether the phenological development of an associated plant species would be well synchronized with spruce seed maturation, we examined the floral development of fireweed (Epilobium angustifolium L.) by dividing the inflorescence into six distinct parts. Weekly harvest on five different sites across the distribution of white spruce in Quebec (Canada) showed a good correlation between the timing of white spruce seed maturation and the beginning of capsule bursting at the base of fireweed inflorescence (r-s = 0.92). These two stages of development correspond to 1276 +- 112 degree-days or 1943 +- 155 thermal units, the latter yielding the greatest precision. Development of each section of the inflorescence progressed successively from the base to the top with a delay ranging between 3 and 7 days. Therefore, it appears possible to forecast the optimal moment for collection of white spruce cones 2 weeks in advance by monitoring the acropetal progression of the floral axis of fireweed. The influence of other factors, such as drainage class, light environment, and intra-population variations are also discussed.
Publication Species: 
Picea glauca (white spruce)
Volume: 
59
Issue: 
1-2
Page Numbers: 
115-125
DOI: 
PubMed: