FIRST- AND SECOND-YEAR EFFECTS OF ACECAP® IMPLANTS AGAINST CONE INSECTS OF BLACK SPRUCE

1992 ◽  
Vol 124 (4) ◽  
pp. 577-585 ◽  
Author(s):  
R.J. West ◽  
K.M.S. Sundaram
Keyword(s):  
Picea Mariana ◽  
Black Spruce ◽  
Insect Damage ◽  
Toxic Metabolite ◽  
Second Year ◽  
Seed Yields ◽  
Strobilomyia Neanthracina

AbstractAcephate implanted in trunks of black spruce, Picea mariana (Mill.) B.S.P., trees in the fall, 3 weeks before female bud flush, and at female bud flush reduced insect damage to cones and increased seed yields for 1 year. Second-year effects of the implants reduced insect damage to cones, but without increased seed yields. In the 2nd year, cones from trees treated at bud flush had the least insect damage and the highest residues of acephate and its toxic metabolite, methamidophos. Damage to treated cones by the spruce cone maggot, Strobilomyia neanthracina Michelson, the dominant insect in untreated cones, was insignificant in the 1st year and was reduced in the 2nd year.

OCCURRENCE OF DEATHWATCH CONE BEETLE, ERNOBIUS BICOLOR WHITE (COLEOPTERA: ANOBIIDAE), IN CONES OF BLACK SPRUCE, PICEA MARIANA (MILL.) B.S.P., IN NOVA SCOTIA

1993 ◽  
Vol 125 (2) ◽  
pp. 403-404 ◽  
Author(s):  
J.D. Sweeney ◽  
G. Gesner ◽  
G. Smith
Keyword(s):  
Nova Scotia ◽  
Picea Mariana ◽  
Black Spruce ◽  
Growing Season ◽  
Extensive Survey ◽  
Seed Yields

An extensive survey of black spruce, Picea mariana (Mill.) B.S.P., in Newfoundland in 1978 disclosed that up to 50% of the old cones remaining on the trees were damaged by the deathwatch cone beetle, Ernobius bicolor White (Schooley 1983; White 1983). This beetle infests black spruce cones produced in the previous year's growing season and also damages cones in storage. Eggs are deposited between the scales and larvae feed within the cone and pupate in the fall or the following spring; their feeding can reduce extracted seed yields by one-half (Schooley 1983).

Potential and Actual Yields of Seed from Black Spruce Cones

1988 ◽  
Vol 64 (1) ◽  
pp. 32-34 ◽  
Author(s):  
V. F. Haavisto ◽  
R. L. Fleming ◽  
D. A. Skeates
Keyword(s):  
Key Words ◽  
Seed Yield ◽  
Picea Mariana ◽  
Black Spruce ◽  
Extraction Technology ◽  
Genetically Improved ◽  
Seed Yields

Black spruce (Picea mariana [Mill.] B.S P.) trees have semi-serotinous cones and disperse seed over a period of years, a fact that suggests possible difficulty in seed release. Reported seed yields per cone are variable, and operational extraction yields are low. It is hypothesized that this could be attributed partially to incomplete extraction. The studies reported herein have shown that actual seed complements within cones are similar to theoretical estimates, ranging from 50 to 110 seeds per cone. The need to improve extraction technology is suggested, especially for genetically improved sources. Key words: black spruce, Picea mariana, cones, cone scales, seeds, seed yield, seeds per cone

Changes in DOC and DON fluxes in response to harvest intensity of black-spruce-dominated forest ecosystems in northwestern Ontario

2009 ◽  
Vol 89 (1) ◽  
pp. 67-79 ◽  
Author(s):  
Dave M Morris
Keyword(s):  
Dissolved Organic Nitrogen ◽  
Organic Nitrogen ◽  
Black Spruce ◽  
Site Type ◽  
Northwestern Ontario ◽  
Clearcut Harvesting ◽  
Second Year ◽  
Forest Floors ◽  
Source Sink ◽  
Site Types

The current study was conducted to quantify and compare dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) fluxes through black-spruce-dominated forests, to compare the source/sink characteristics of sphagnum- versus feathermoss-dominated forest floors, and to identify changes in DOC and DON flow patterns occurring as a result of clearcut harvesting. After 2 yr of pre-harvest monitoring, replicated, experimental harvests of varying intensities of biomass removals were conducted followed by 4 yr of post-harvest sampling. Prior to harvest, the upland site type, dominated by feathermoss, was a significant source of DOC and DON, whereas, the wet-sphagnum-dominated sites exported minor amounts of these solutes. After harvest, DOC and DON fluxes peaked in the second year, but then dropped off significantly to at or below pre-harvest levels. On the upland site type, chipper debris appeared to be a major source of DOC and DON generating fluxes well above the pre-harvest levels. On the wetter site types, it appeared that microclimate differences between harvest treatments had a stronger influence on DOC and DON production than did the amount or type of harvest residue. Full-tree harvesting did not significantly alter the production of DOC and DON when compared with stem-only harvesting on the sites included in this study. Key words: DOC, DON, forest floor leachate, black spruce, harvesting response

Clonal and nonclonal genetic structure of subarctic black spruce (Picea mariana) populations in Yukon territory

Botany ◽  
2011 ◽  
Vol 89 (2) ◽  
pp. 133-140 ◽  
Author(s):  
Marios Viktora ◽  
Rodney A. Savidge ◽  
Om P. Rajora
Keyword(s):  
Genetic Structure ◽  
Picea Mariana ◽  
Black Spruce ◽  
A Priori ◽  
Nuclear Genome ◽  
Yukon Territory ◽  
Fire Disturbance ◽  
Clone Size ◽  
Flat Terrain ◽  
Individual Trees

Black spruce (Picea mariana) reproduces sexually from seeds and asexually by layering. There is a prevalent concept that clonal reproduction maintains populations of this species in the subarctic and arctic regions. We used microsatellite DNA markers of the nuclear genome to investigate the genetic structure of montane and subalpine black spruce populations from the Western Yukon Plateau in relation to this concept. Sixty individual trees at a minimum distance of 4 m from each other were sampled from each of four populations and individual trees were genotyped for eight microsatellite loci. Each of the 60 individuals from three montane pure black spruce populations growing on flat terrain at relatively low elevations had unique multilocus genotypes, indicating an absence of clonal structure in those populations. However, in an anthropologically undisturbed climax white spruce-dominated subalpine black spruce population on a northwest slope near Mount Nansen, the majority of the sampled individuals belonged to eight genetically distinct clones (genets). Clone size differed by altitude, the dominant genet being nearest the timberline–tundra ecotone. The results indicate that black spruce reproduction is variable and adaptive, being primarily sexual in flat-terrain montane populations previously subjected to fire disturbance, but mixed vegetative–sexual in the anthropogenically undisturbed subalpine population. This study is the first to employ molecular markers a priori to examine the mode of reproduction in natural black spruce populations.

scholarly journals Comparative Height Growth of Eastern Larch and Black Spruce in Northwestern Ontario

1978 ◽  
Vol 54 (6) ◽  
pp. 296-297 ◽  
Author(s):  
Douglas A. Mead
Keyword(s):  
Picea Mariana ◽  
Black Spruce ◽  
Height Growth ◽  
Larix Laricina ◽  
Stem Analysis ◽  
Northwestern Ontario ◽  
Analysis Methods ◽  
Spruce Stands

Height growth of eastern larch (Larix laricina (Du Roi) K. Koch) and black spruce (Picea mariana (Mill.) B.S.P.) was determined using standard stem analysis methods on trees from two sites in northwestern Ontario. The data were obtained from mixed larch-spruce stands which were relatively undisturbed. The larch exhibited substantially better height growth than the spruce through age 65.

SEASONAL DAMAGE BY INSECTS AND SQUIRRELS TO FEMALE REPRODUCTIVE STRUCTURES OF BLACK SPRUCE, PICEA MARIANA (MILL.) B.S.P.

1988 ◽  
Vol 120 (12) ◽  
pp. 1113-1121 ◽  
Author(s):  
Y.H. Prévost ◽  
J.E. Laing ◽  
V.F. Haavisto
Keyword(s):  
Picea Mariana ◽  
Black Spruce ◽  
Choristoneura Fumiferana ◽  
Tamiasciurus Hudsonicus ◽  
Red Squirrel ◽  
Red Squirrels ◽  
Reproductive Structures ◽  
Cone Axis ◽  
Viable Seeds ◽  
Cone Growth

AbstractThe seasonal damage to female reproductive structures (buds, flowers, and cones) of black spruce, Picea mariana (Mill.) B.S.P., was assessed during 1983 and 1984. Nineteen insects (five Orders) and the red squirrel, Tamiasciurus hudsonicus (Erxleben), were found feeding on these reproductive structures. Collectively, these organisms damaged 88.9 and 53.5% of the cones in 1983 and 1984, respectively. In the 2 years, Lepidoptera damaged 61.8% of the cones in 1983 and 44.4% of the cones in 1984. The spruce budworm, Choristoneura fumiferana (Clem.), and the spruce coneworm, Dioryctria reniculelloides Mut. and Mun., were the most important pests. Cones damaged by Lepidoptera could be classed into three categories: (a) severe, yielding no seeds; (b) moderate, yielding 22.3 seeds per cone; and (c) light, yielding 37.5 seeds per cone. Undamaged cones yielded on average 39.9 seeds per cone. Red squirrels removed 18.8% of the cones in 1983 and none in 1984. The spruce cone axis midge, Dasineura rachiphaga Tripp, and the spruce cone maggot, Lasiomma anthracinum (Czerny), caused minor damage in both years. Feeding by spruce cone axis midge did not reduce cone growth significantly or the number of viable seeds per cone, but feeding by the spruce cone maggot did. During both years new damage by insects to the female reproductive structures of the experimental trees was not observed after mid-July. In 1983 damage by red squirrels occurred from early to late September. In 1984 damage to cones on trees treated with dimethoate was 15.6% compared with 53.5% for untreated trees, without an increase in the number of aborted cones.

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