In Newfoundland, the spruce budworm has caused a pronounced decrease in cone production by balsam fir. Severe defoliation reduced the size and number of shoots upon which cones are usually produced. The budworm did not feed on reproductive buds nor influence the number of buds that continued development to form ovulate flowers. However, virtually all of these flowers or the young cones that developed from them were killed by budworm on severely defoliated trees.A Terre-Neuve, la tordeuse des bourgeons de I'epinette a provoque une baisse importante de la production des cbnes par le sapin baumier. La defoliation marquee a reduit les dimensions et le nombre de pousses sur lesquelles apparaissent d'habitude les cbnes. La tordeuse n'a pas attaqu6 les bourgeons reproductifs ni influence le nombre de bourgeons qui sont devenus des fleurs femelles. Cependant, presque toutes ces fleurs ou les jeunes cbnes qui s'en sont d6veloppes ont ete tues par la tordeuse sur des arbres nettement defeuilles.

The effects of cone storage period and pregermination treatment on seed maturity and dormancy were compared for cones of white spruce (Piceaglauca (Moench) Voss) collected from individual trees in 1984 and 1988. Seeds were extracted from cones and germinated after 2 or 6 weeks of cone storage in 1984 and after 2, 4, 6, 10, or 14 weeks in 1988. Based on cumulative degree-days, seeds were more mature at collection time in 1988 than in 1984. Seeds from 1984 cones stored for 6 weeks matured during storage, and both germination percentage (GP) and rate of germination (GR) were significantly improved. In contrast, storage up to 14 weeks in 1988 did not increase GP and GR, as seed had attained maturity prior to cone collection. Seed dormancy was present in both 1984 and 1988. Significant improvements in GP and GR were achieved in 1984 with a pregermination treatment even before seed maturity was attained. Prechilling of seed after 6 weeks of cone storage increased GP from 60 to 95% in 1984 and 64 to 89% in 1988.

No abstract

Cones were collected in 1984 at the time of natural seed dissemination from 18 open-pollinated, 30-year-o!d white spruce (Picea glauca(Moench) Voss) trees at 1.2, 2.4, and 4.9 m spacings in a demonstration seed production area at Petawawa National Forestry Institute. Cones were stored in a well-ventilated building for 2 to 6 weeks before seed extraction.Cones length, full-seed-yield per cone, and full-seed weight were greatest for cones collected from trees at the 1.2 m spacing. When cones were stored for 2 weeks, non-prechilled and prechilled seeds averaged 32.0 ± 1.0% [Formula: see text] and 62.3 ± 1.0% germination, respectively. When cones were stored for 6 weeks, non-prechilled and prechilled seeds averaged 61.3 ± 1.2% and 94.7 ± 0.5% germination, respectively. The higher germination percentage, germination rate, and lower tree to tree variation for prechilled seeds from cones stored for 6 weeks indicate that seed maturation was promoted by post-harvest cone storage prior to seed extraction. Average seed dormancy remained about the same from 2 to 6 weeks of storage; however, seeds from some trees became more dormant with the storage whereas those from others became less dormant. Relationship between seed weight and germination was weak. Key words: Cone storage, seed prechilling, germination percentage, germination rate, seed maturation, seed dormancy, seed weight, seed sorting.

The biology of a newly discovered deathwatch beetle that infests one-year-old and older black spruce Picea mariana B.S.P. cones is described. This pest reduces the amount of seed retained in the cones that persist on the trees for many years. Up to 50% of a cone crop at a location may be damaged and annual damage between 1963 and 1979 averaged up to 18% for samples from 33 locations. Undamaged cones may not retain enough seed to naturally re-establish stands following harvest or fire. Substantial seed losses were observed when infested cones were harvested for seed extraction. This cone beetle has been recorded only from Newfoundland.