Summary:
Published in The Forestry Chronicle 88(4): 448-457
Cold damage leads to the rejection of millions of seedlings each year in northern forest nurseries. Nursery managers need a procedure to estimate the degree of hardening at a specific time in order to make decisions to avoid seedling loss. Estimates based on variables that are quick and easy to measure such as thermal time, a variable quantifying the cumulative effect over time of temperatures below a given threshold, and apical dry mass ratio (DM/FM) hold particular promise. In this study, two-year-old white spruce containerized seedlings were subjected to artificial freezing tests. The progression of DM/FM during the fall was determined and the thermal time was quantified by calculating hardening degree days (HDD) based on air temperature and a specific threshold for white spruce. Results establish that cold tolerance thresholds are associated with easily identifiable specific DM/FM and HDD values for nursery × species × seed source combinations.
File:
Sector(s):
Forests
Catégorie(s):
Scientific Article
Theme(s):
Forestry Research, Forests, Seeds and Forest Seedlings Production
Departmental author(s):
Author(s):
CARLES, Sylvie, Mohammed S. LAMHAMEDI, Debbie C. STOWE, Linda VEILLEUX and Hank A. MARGOLIS
Year of publication:
2012
Format:
Keyword(s):
épinette blanche, dommage causé par le gel, endurcissement, ratio de matière sèche des apex, degrés jours d'endurcissement, Picea glauca, article scientifique de recherche forestière, production de semences et de plants, seeds and forest seedlings production, cold damage, hardening, apical dry mass ratio, hardening degree days