scholarly journals Seed Production in Grafted Clonal Orchards at Longlac, Ontario

1982 ◽  
Vol 58 (1) ◽  
pp. 31-34 ◽  
Author(s):  
J. A. McPherson ◽  
E. K. Morgenstern ◽  
B. S. P. Wang

One seed orchard each of black spruce (Picea mariana) [Mill.] B.S.P.) and white spruce (Picea glauca) [Moench] Voss) was established in northern Ontario gradually during the 1958-78 period. Each species was represented by approximately 45 clones and 450 ramets. During the whole period, records were kept of cone production by individual ramets and of seed production by clones expressed as average number of seeds per cone extracted and germinated. Substantial cone production began 8 years after grafting in black spruce and after 10 years in white spruce. The figures indicated that a clonal orchard of black spruce planted at 5 × 5 m spacing (400 ramets) produces approximately 1 million sound seeds per ha per year; the white spruce equivalent is 900 000. Conditions of cone development and cone storage and damage by insects and fungi can reduce germination of the sound seed harvested by about 20%.

1982 ◽  
Vol 58 (2) ◽  
pp. 96-99 ◽  
Author(s):  
B. Payandeh ◽  
V. F. Haavisto

Nonlinear regression equations were developed to describe seed production and dispersal in black spruce (Picea mariana [Mill.]B.S.P.)in northern Ontario. Solution of the equations can provide useful information beyond the range of the original data, because of the flexibility of the models used. For example, solution of equations 1-3 indicates that cones from intermediate crown class trees initially have about twice as many seeds as those of either the dominant or codominant trees, but disperse their seeds at a much faster rate. Average number of seeds per cone for all three crown classes is about 7 after 10 years. Older cones of the intermediate crown class trees have fewest seeds per cone. Solution of equation 4 indicates that average seed viability is about 53% and decreases only slightly during the first three years. It then decreases very rapidly up to 12 years to about 5%. Similarly, equations 6 and 7 may be solved to determine an optimum strip-cut width for sufficient seedfall across the strip to produce satisfactory regeneration.


1983 ◽  
Vol 59 (4) ◽  
pp. 189-191 ◽  
Author(s):  
A. A. Alm

Black spruce (Picea mariana (Mill.) B.S.P.) and white spruce (Picea glauca (Moench) Voss) styrob-lock and paperpot and 3-0 and 2-2 seedlings were planted spring and fall. After four seasons of growth the container seedlings had survival and height growth as good or better than the nursery seedlings. There were no differences in performance between the two container systems. The 2-2 stock generally had better survival than the 3-0 stock. Survival of fall-planted stock was equal to or better than that of the spring-planted stock. Key words: white spruce, black spruce, styroplugs, paper pots, seedlings, transplants, artificial regeneration, fall vs spring planting


1981 ◽  
Vol 113 (10) ◽  
pp. 949-951 ◽  
Author(s):  
W. H. Fogal ◽  
D. A. Winston ◽  
S. M. Lopushanski ◽  
D. A. MacLeod ◽  
A. J. Willcocks

White spruce, Picea glauca (Moench) Voss, is a major commercial tree species used in reforestation programs throughout Canada, and seed requirements cannot be met in some years because of insect damage and the periodic nature of cone crops. The spruce budworm, Choristoneura fumiferana (Clem.), feeds on buds and cones of its hosts, causing a pronounced decrease in cone production (Schooley 1978). A current outbreak in northeastern Ontario poses a serious threat to white spruce seed supply from high value, managed seed production areas. Therefore, in 1979, we began an experiment to determine whether carbofuran, a systemic insecticide, could be used to protect buds and cones when applied to soil. We chose carbofuran because it has proved successful for control of some insects in seed orchards in the southeastern United States (DeBarr 1978)


1986 ◽  
Vol 62 (5) ◽  
pp. 446-450 ◽  
Author(s):  
S. W. J. Dominy ◽  
J. E. Wood

Seeding trials were established on four different sites in northern Ontario (46°41′N to 49°19′N) in 1979 and 1980. Jack pine (Pinus banksiana Lamb.) was seeded on two medium sand sites, black spruce (Picea mariana [Mill.] B.S.P.) on a sandy clay site, and white spruce (P. glauca [Moench] Voss) on a clay site. Conventional bare spot seeding was compared with spot seeding under Finnish-designed plastic shelters. At least two seeding dates were compared in each trial. Third- and fifth-year stocking and fifth-year height data are presented.Stocking of all three species was increased, regardless of sowing date, when shelters were used. With the exception of June-sown black spruce and one June sowing of jack pine, height growth was not significantly improved through the use of seed shelters. Shelters may prove to be a viable regeneration option only on cooler, exposed sites with little vegetative competition. Key words: Shelter spot seeding, bare spot seeding, Pinus banksiana Lamb., Picea mariana [Mill.] B.S.P., P. glauca [Moench] Voss.


1990 ◽  
Vol 68 (12) ◽  
pp. 2583-2589 ◽  
Author(s):  
S. M. Attree ◽  
T. E. Tautorus ◽  
D. I. Dunstan ◽  
L. C. Fowke

Somatic embryo maturation, germination, and soil establishment frequencies were compared for two conifer species, white and black spruce (Picea glauca and Picea mariana). The comparison of the two species regenerated and established in soil under the same conditions showed black spruce to be the most responsive. Shorter exposure times to 32 μM abscisic acid were not as effective as maturation on a medium containing 16 μM abscisic acid for 28 days. This gave similar maturation frequencies for the two species (6–8%), and germination frequencies of 64% for white spruce and over 73% for black spruce. Over 1800 black and white spruce plantlets were recovered, and more than 400 were transferred from in vitro to nonsterile conditions. Sixty percent (160) of the black spruce plantlets survived transfer and continued to grow vigorously. By comparison only 18% (29) of the white spruce plantlets survived, and half of these rapidly produced dormant buds and underwent no further shoot growth. White spruce plants that did not produce dormant buds grew vigorously. These results indicate that there are large differences in the ability of these closely related species to respond to plantlet establishment following regeneration from somatic embryos, and that black spruce is highly responsive to micropropagation by this method. Key words: Picea glauca, Picea mariana, somatic embryogenesis, maturation, germination, soil establishment.


2012 ◽  
Vol 42 (9) ◽  
pp. 1733-1743 ◽  
Author(s):  
Hugues Power ◽  
Valerie LeMay ◽  
Frank Berninger ◽  
Derek Sattler ◽  
Daniel Kneeshaw

Black spruce ( Picea mariana (Mill.) Britton, Sterns & Poggenb.) and white spruce ( Picea glauca (Moench) Voss) are phylogenetically proximal species that differ in productivity. Crown characteristics of these two species have not been extensively studied, in spite of the importance of these two species to the Canadian boreal forest and the importance of tree crowns for understanding and modelling tree growth. In this paper, we characterize and compare the crown lengths, crown profiles (i.e., radii), shapes, and surface areas of these two species using 65 white spruce and 57 black spruce trees destructively sampled in the provinces of Alberta, Ontario, and Quebec, Canada. Crown length was measured on every sample tree, while crown profile was obtained by reconstructing crowns from branch measurements. Our results showed that crown lengths did not differ between these two species given the same tree size and growth conditions. However, these two species establish under different growth conditions resulting in crown length differences. Further, differences in crown radii and profiles were found even under the same growth conditions. White spruce trees had wider crown radii and profiles changed from a parabola to a cone shape under increased density. As a result, differences in crown surface areas were found.


1987 ◽  
Vol 65 (4) ◽  
pp. 656-659 ◽  
Author(s):  
Inger Hakman ◽  
Larry C. Fowke

Embryogenic callus was initiated from immature embryos of Picea glauca (white spruce) and Picea mariana (black spruce) cultured on defined media supplemented with 2,4-dichlorophenoxyacetic acid (1 × 10−5 M), N6-benzyladenine (5 × 10−6 M), and 1% sucrose. Seeds from cones stored at 4 °C for up to 3 months yielded embryogenic callus. Much higher frequencies of embryogenic callus were obtained from white spruce than from black spruce. Embryogenic callus contained loosely organized cells and somatic embryos of various sizes. The embryos consisted of a cluster of tiny dividing cells (embryonic region) with attached large vacuolated cells (suspensor region). Upon subculture of embrogenic callus to media either lacking growth regulators or with reduced concentrations (5 × 10−7 M, 2,4-dichlorophenoxyacetic acid and 5 × 10−6 M N6-benzyladenine) somatic embryos could be stimulated to develop into plantlets.


2010 ◽  
Vol 86 (2) ◽  
pp. 193-199 ◽  
Author(s):  
G. Geoff Wang ◽  
Kevin J Kemball

Two boreal mixedwood stands burned by the 1999 Black River wildfire in southeastern Manitoba, Canada were selected to study the effect of fire severity on early survival and growth of planted jack pine (Pinus banksiana), black spruce (Picea mariana) and white spruce (Picea glauca) seedlings. In each stand, three fire severity classes (scorched, lightly burned, and severely burned) were identified based on the degree of forest floor consumption. Fire severity was not a significant factor on mortality. No mortality difference was found among species, except for year 5 when jack pine had significantly higher mortality than both black spruce and white spruce. Jack pine and black spruce had their highest mortality in year 4, while white spruce had its highest mortality in year 1. Under natural competition, seedling growth increased with increasing fire severity. When competition was removed, fire severity did not affect seedling growth. Regardless of fire severity and competition, jack pine had better diameter and height growth than black spruce, which, in turn, grew slightly taller than white spruce. Planted seedlings faced less intense vegetation competition on severely burned plots compared to scorched or lightly burned plots. Regardless of fire severity and species, competition increased with time since planting. Our study results indicate that planting immediately after a wildfire is a viable option to establish conifer components on burned boreal mixedwood stands. Key words: fire severity, plantation, regeneration, Pinus banksiana, Picea mariana, Picea glauca


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