Genetic variation of red spruce in the Maritimes
Red spruce, Picearubens Sarg., from 30 provenances was tested over a 23-year period at six locations in the Maritimes Region of Canada. Twenty-eight of the provenances were from the Maritimes Region and two were from West Virginia. Hybrid index was used to distinguish pure red spruce from red–black spruce derivatives. Trees from three of the Maritimes provenances were considered to be of hybrid origin. These three provenances produced the fastest-growing trees in the tests. The genetic variation pattern, at the provenance level, in pure red spruce of Maritimes origin is not well defined. Use of seed from provenances identified as superior for reforestation would result in about 10% greater height and diameter growth than would be obtained from average seed. The use of seed of poor provenances could result in a corresponding loss of growth. Height at ages 10, 15, and 23 years and diameter at age 23 years were all strongly correlated, suggesting that superior provenances of red spruce can be identified at age 10. The Maritimes Region can be considered as a single breeding zone for tree improvement efforts with red spruce.