Dispersal of Pissodes strobi in putatively resistant white spruce in Vernon, BC

1996 ◽  
Vol 72 (4) ◽  
pp. 381-387 ◽  
Author(s):  
R. L. McIntosh ◽  
J. A. McLean ◽  
R. I. Alfaro ◽  
G. K. Kiss

White pine weevil Pissodes strobi behaviour was observed in a five-year-old plantation of white spruce in Vernon, British Columbia. Seasonal weevil-host interactions were monitored in four susceptible and four putatively resistant reciprocal cross family pairs in three of five replicates. Classification of susceptibility to weevil attack was based on previous weevil attack history. Performance of eight reciprocal cross pairs was ranked as a function of visitation, oviposition and brood establishment resulting in top-kill. The four putatively resistant family crosses ranked 1 to 4 for resistance to weevil attack, while the four susceptible crosses were ranked 5 to 8 and were consistently attacked. Seasonal and diurnal weevil movement was monitored using mark-recapture techniques. Diurnally, weevils moved within the tree. Feeding occurred at dawn in the leader and upper laterals after which weevils moved down the tree into the forest floor during the high mid-summer temperatures. Later in the season weevils fed in mid-morning on the leader and on the under-sides of lateral branches. A dispersal index was developed to describe seasonal movement. Weevils did not move far throughout the season. Overall dispersal index for both males and females was less than 0.24 m, suggesting that on average, weevils do not move further than the adjacent tree throughout the season after mating and oviposition. Key words: Dispersal, pest management, Pissodes strobi, resistance, silviculture, white spruce

1997 ◽  
Vol 75 (4) ◽  
pp. 568-573 ◽  
Author(s):  
René I. Alfaro ◽  
Fangliang He ◽  
Elizabeth Tomlin ◽  
G. Kiss

Examination of the bark from the uppermost lateral branches of white spruce, Picea glauca (Moench) Voss, indicated that trees resistant to attack by the white pine weevil, Pissodes strobi Peck, had significantly higher number and density of vertical resin canals per unit of bark area (mm2) than susceptible trees. The number and density of resin canals were also positively correlated with tree growth rate, an indicator of tree vigor. The density of the resin canals found near the periphery of the bark (outer resin canals) had higher correlation with resistance and growth than inner resin canals. Measurements of resin canals on the bark of lateral branches correlated well with measurements on the bark of the leader of the same tree, indicating that lateral samples could be used to screen white spruce for resistance to weevils. Key words: Picea glauca, Pissodes strobi, pest management, tree genetics.


1999 ◽  
Vol 131 (1) ◽  
pp. 131-136 ◽  
Author(s):  
Rory L. McIntosh

AbstractA simple nontoxic technique to mark and reference the white pine weevil Pissodes strobi (Peck) is described. This marking technique was used to track the movement of individuals to the cohort level through time and space in a young white spruce plantation.


2006 ◽  
Vol 82 (4) ◽  
pp. 538-549 ◽  
Author(s):  
Gaëtan Daoust ◽  
Marie-Josée Mottet

A study to assess the effects that major deformations in merchantable stems of Norway spruce (Picea abies [L.] Karst.), caused by the white pine weevil (Pissodes strobi [Peck]), have on lumber productivity and quality was performed on logs obtained from the second commercial thinning operation in three weevil-affected plantations. Deformed stems were found to be 6.3% shorter than undeformed stems and their lumber characteristics — merchantable volume, number of board feet and lumber monetary value — were 14.7%, 20.6% and 23.7% lower, respectively. However, when the respective proportions of deformed and undeformed stems were analyzed for a given plantation over a time horizon of a complete rotation, these shortfalls almost disappeared, with a loss of less than 3% being noted for total merchantable volume. The presence/absence of major deformations had no effect on visual grading of the lumber, which considers defects such as wane, knots and compression wood. For two of the three sites studied, almost 75% of the lumber was graded as Select Structural, No. 1 or No. 2. The plantation site and its characteristics (spacing and level of thinning) were found to have a more significant effect than deformations on productivity, lumber quality and monetary value. Furthermore, using the same methodology, one of the Norway spruce sites was compared with a white spruce (Picea glauca [Moench] Voss) plantation containing trees of similar quality and height but no weevil problems. The Norway spruce stems, including those with deformations, were found to yield higher merchantable and usable log volumes, a larger number of board feet and a higher monetary value than the white spruce. On average, for the diameter-at-breast-height values tested — 14 to 23 cm — the monetary value of the lumber was 26% higher for Norway spruce. These findings are largely attributable to the less pronounced taper of Norway spruce. In conclusion, in spite of weevil attacks and its negative impact, Norway spruce trees growing on sites of moderate to very good quality maintain lumber potential, in terms of both quantity and quality for second thinning logs. The negative impact should gradually diminish at the time of next thinnings and final harvest. Key words: white pine weevil, Pissodes strobi (Peck), Norway spruce, Picea abies (L.) Karst., wood quality, plantation, productivity


2006 ◽  
Vol 82 (5) ◽  
pp. 745-756 ◽  
Author(s):  
Gaëtan Daoust ◽  
Marie-Josée Mottet

A study to assess the effects that major deformations in merchantable stems of Norway spruce (Picea abies [L.] Karst.), caused by the white pine weevil (Pissodes strobi [Peck]), have on lumber productivity and quality was performed on logs obtained from a second commercial thinning operation in three weevil-affected plantations. Deformed stems were found to be 6.3% shorter than non-deformed stems and their lumber characteristics, i.e., merchantable volume, number of board feet and lumber monetary value, were 14.7%, 20.6% and 23.7% lower, respectively. However, when the respective proportions of deformed and non-deformed stems were analyzed for a given plantation over the time horizon of a complete rotation, these shortfalls almost disappeared, with a loss of less than 3% being noted for total merchantable volume. The presence/absence of major deformations had no effect on visual grading of the lumber, which takes defects such as wane, knots and compression wood into account. For two of the three sites studied, almost 75% of the lumber was graded as Select Structural, No. 1 or No. 2. The plantation site and its characteristics (spacing and level of thinning) were found to have a more significant effect than deformations on productivity, lumber quality and monetary value. Furthermore, using the same methodology, one of the Norway spruce sites was compared with a white spruce (Picea glauca [Moench] Voss) plantation containing trees of similar quality and height, but with no weevil problems. The Norway spruce stems, including those with deformations, were found to yield higher merchantable and usable log volumes, a larger number of board feet and a higher monetary value than white spruce. On average, for the diameter at breast height values tested — 14 to 23 cm — the monetary value of the lumber was 26% higher for Norway spruce. These findings are largely attributable to the less pronounced taper of Norway spruce. In conclusion, in spite of weevil attacks and their negative impact, Norway spruce trees growing on sites of moderate to very good quality maintain lumber potential, in terms of both quantity and quality, for second thinning logs. The negative impact should gradually decrease at the time of next thinnings and final harvest. Key words: white pine weevil, Pissodes strobi (Peck), Norway spruce, Picea abies (L.) Karst., wood quality, plantation, productivity


2006 ◽  
Vol 82 (5) ◽  
pp. 712-722
Author(s):  
Marie-Josée Mottet ◽  
Gaëtan Daoust ◽  
S Y Zhang

We studied the lumber characteristics of 148 trees taken for that purpose during commercial thinning operations in three Norway spruce (Picea abies [L.] Karst.) plantations, aged from 32 to 34 years, which had been attacked by the white pine weevil (Pissodes strobi [Peck]). The trees, with diameters ranging from 14 to 23 cm, were grouped into three quality classes according to the number of major deformations caused by the weevil. The effects of the deformations on rigidity, bending strength, wood density and lumber defects were examined. Results show that in general the deformations caused by the weevil do not affect the lumber properties of Norway spruce on sites of medium- to high-quality. For the three Norway spruce plantations, the mean values of the modulus of elasticity (MOE) of the lumber vary from 8510 to 9357 MPa, and for the modulus of rupture (MOR) range from 36.0 to 42.5 MPa, whereas wood density varies from 324 to 343 kg·m-3. For comparison purposes, the same measurements were taken on lumber from 38 trees in a white spruce (P. glauca [Moench] Voss) plantation that was unaffected by the weevil, but otherwise comparable to the Norway spruce plantation on one of the sites studied. The lumber properties from the Norway spruce taken from deformed or undeformed stems are 34% superior to the white spruce for the MOE, 20% for the MOR and 8% for wood density. The smaller knots in the Norway spruce could explain this difference. On the other hand, a visual classification of this type of wood reveals few differences in the lumber's bending strength or rigidity. Key words: Norway spruce, Picea abies, wood characteristics, MOE, MOR, wood density, lumber, white pine weevil, Pissodes strobi, white spruce, Picea glauca


2006 ◽  
Vol 82 (6) ◽  
pp. 834-843 ◽  
Author(s):  
Marie-Josée Mottet ◽  
Gaëtan Daoust ◽  
S Y Zhang

We studied the lumber characteristics of 148 trees acquired for that purpose during commercial thinning operations in three Norway spruce (Picea abies [L.] Karst.) plantations, aged from 32 to 34 years, which had been attacked repeatedly by the white pine weevil (Pissodes strobi [Peck]). The trees, with diameters ranging from 14 to 23 cm, were grouped into three quality classes according to the number of major deformations caused by the weevil. The effects of the deformations on bending strength and stiffness, wood density and lumber defects were examined. Results show that in general deformations caused by the weevil do not affect the lumber properties of Norway spruce on sites of medium to high quality. For the three Norway spruce plantations, the mean values of the modulus of elasticity (MOE) of the lumber varied between 8510 and 9357 MPa, and for the modulus of rupture (MOR) they ranged from 36.0 to 42.5 MPa, whereas wood density varied from 324 and 343 kg·m-3. For comparison purposes, the same measurements were taken on lumber from 38 trees in a white spruce (P. glauca [Moench] Voss) plantation that was unaffected by the weevil, but comparable to the Norway spruce plantation on one of the sites studied. The lumber properties from Norway spruce taken from deformed or undeformed stems were 34% superior to white spruce for MOE, 20% for MOR and 8% for wood density. The smaller knots in Norway spruce could explain this difference. On the other hand, a visual grading of this type of wood reveals few differences in lumber strength and stiffness. Key words: Norway spruce, Picea abies, wood characteristics, MOE, MOR, wood density, lumber, white pine weevil, Pissodes strobi, white spruce, Picea glauca


1996 ◽  
Vol 26 (6) ◽  
pp. 967-972 ◽  
Author(s):  
René I. Alfaro ◽  
G.K. Kiss ◽  
A. Yanchuk

The intensity of the traumatic resin response in white spruce, Piceaglauca (Moench) Voss, to attack by the white pine weevil, Pissodesstrobi Peck, was studied in trees with different severities of attack. The response level was highest in trees where the attacks failed, i.e., where eggs were laid but the brood was killed and no adults emerged. Successfully attacked trees had, on average, only 62% of the response intensity of trees with failed attacks. Response intensity in trees that had been subjected only to feeding was much lower, at 42% of the failed attack response. Healthy unattacked trees showed no or little traumatic resin response. Response intensity varied in a nonlinear fashion with the number of eggs laid, increasing rapidly from zero in healthy trees, being highest in trees having between 10 and 60 egg punctures, and progressively lower again in trees with higher numbers of egg punctures. For a given number of egg punctures, resistant white spruce trees had a consistently higher traumatic resin response than susceptible trees. The number of eggs laid on a leader was inversely related to the intensity of the traumatic resin response and to the timing of the attack. Fewer eggs were laid on leaders with high traumatic resin response or attacked late in the season than on leaders with lower resin response or attacked early in the season.


2010 ◽  
Vol 86 (6) ◽  
pp. 775-779 ◽  
Author(s):  
Alice Verrez ◽  
Dan Quiring ◽  
Thibaut Leinekugel Le Cocq ◽  
Greg Adams ◽  
Yill Sung Park

White pine weevil (Pissodes strobi Peck) damage was evaluated in one white pine (Pinus strobus L.) and four jack pine(Pinus banksiana Lamb) half-sib family test sites to determine the role of tree genotype in resistance to the weevil. Halfsibfamily explained a significant proportion of the variation in weevil attack at all sites. Estimates of family (0.16-0.54)and individual (0.09-0.24) heritabilities of jack pine resistance to white pine weevil were moderate. Estimates of family(0.37) and individual (0.22) heritability of resistance of white pine to the weevil were also moderate when the percentageof test trees damaged by the weevil was relatively low, but were insignificant four years later when more than three-quartersof trees were damaged. Significant positive correlations between mean tree height and mean incidence of trees damagedby the weevil were observed for four of seven site-years but relationships were weak, suggesting that any cost, withrespect to height growth, to breeding weevil resistant trees may be small.Key words: Pinus, Pissodes strobi, trade-offs, tree improvement, tree resistance, white pine weevil.


1982 ◽  
Vol 11 (3) ◽  
pp. 555-564 ◽  
Author(s):  
Wayne N. Dixon ◽  
Mark W. Houseweart

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