Publications by H. Piene http://cfs.nrcan.gc.ca/authors/read/11134 Publications by H. Piene en-ca 2006-03-17 00:00:00 MST 2006-03-17 00:00:00 MST webmaster@nofc.cfs.nrcan.gc.ca Influence of pre-commercial thinning of balsam fir on defoliation by the balsam fir sawfly http://cfs.nrcan.gc.ca/publications?id=26068 Pre-commercial thinning, whereby tree densities are reduced to diminish competition and maximize tree growth, is one of the most frequently used silvicultural practices in North America. We carried out field surveys in western Newfoundland and in eastern Nova Scotia, Canada, in pre-commercially thinned and unthinned stands of balsam fir (Abies balsamea (L.) Mill.) that had been defoliated by the balsam fir sawfly, Neodiprion abietis (Harr.), to determine if pre-commercial thinning increased the susceptibility of stands to insect defoliators. Except for stands sampled at the new and increasing stage of an outbreak, both egg densities of, and defoliation by, N. abietis were higher in thinned than unthinned stands. Higher levels of defoliation in thinned than unthinned stands were usually associated with higher levels of defoliation on intermediate-aged foliage. An estimate of tree vigor, used to predict future tree growth rate, was only weakly related to defoliation levels and it is, therefore, uncertain if higher defoliation in thinned stands would result in lower future growth rates than for trees in unthinned stands. Fri, 17 Mar 2006 http://cfs.nrcan.gc.ca/publications?id=26068 Relationship between balsam fir sawfly density and defoliation in balsam fir http://cfs.nrcan.gc.ca/publications?id=26532 A 2-year field study was carried out with the balsam fir sawfly, Neodiprion abietis (Harris), on balsam fir, Abies balsamea (L.) Mill., to determine: (1) the temporal patterns of defoliation and foliage weight loss associated with early and late-larval instars; (2) the losses in branch and tree stem volume growth as a result of defoliation by larvae; and (3) the extent to which individual branches are autonomous, and their utility for predicting stem growth losses due to defoliation. In addition, this study also permitted us to determine the relationships between defoliation or foliage weight and branch and tree stem volume growth. Defoliation, foliage weight loss and larval development occurred more quickly in the first year due to warmer temperatures, but final levels of defoliation and foliage weight loss were similar in both years. Cumulative defoliation levels increased from <5% at the beginning of the study to 35 and 63%, respectively, in fall 1999 and 2000. Defoliation was greatest on 1-year-old foliage in both years and most defoliation and foliage weight loss occurred after the initiation of third instar. Based upon individual year-volume increment relationships for each branch and tress, mean volume increment loss in 1999 and 2000, respectively, was 20 and 42% for observation branches and 12 and 35% for tree stems. Similar growth loss estimates of 12 and 46%, respectively, for 1999 and 2000, were obtained when comparing the mean specific volume increment for control and observation branches. Foliage weight after sawfly attack was related to branch and stem volume growth, but defoliation was only related to branch volume loss. Although branch and tree stem growth were strongly related, growth losses in a branch were not related to those in a tree stem. Branch removal and measurement is a practical alternative to cutting trees to estimate stem volume growth in balsam fir. Thu, 12 Oct 2006 http://cfs.nrcan.gc.ca/publications?id=26532 Spruce budworm defoliation and growth loss in young balsam fir: relationships between volume growth and foliage weight in spaced and unspaced, defoliated and protected stands http://cfs.nrcan.gc.ca/publications?id=23798 Foliage weight (FW) and tree volume, volume increment (VI), and specific volume increment (SVI) were examined throughout a spruce budworm (Choristoneura fumiferana (Clem.)) outbreak cycle from 1976 to 1984, for young balsam fir (Abies balsamea (L.) Mill.). Treatments were spaced and unspaced, defoliated and protected (annual insecticide spraying to prevent defoliation). Six years into the outbreak, FW in defoliated plots reached its minimum levels, representing a reduction of 83.3 and 84.3% for spaced and unspaced stands, respectively, compared with the protected stand. For surviving trees, FW recovery was rapid and substantial (threefold to fivefold over 3 years), due to the release of suppressed buds. Still, at the end of the outbreak, FW was reduced by 37.5 and 68.5% for spaced and unspaced stands, respectively. VI was reduced by 92.5 and 91.1% and SVI by 92.0 and 89.3% for spaced and unspaced stands, respectively, compared with the protected stand. This severe budworm outbreak reduced growth rates by about the same level, regardless of initial differences in growth rates and density. By the end of the outbreak, volume was reduced by 32.6 and 54.1 m3/ha for spaced and unspaced stands, respectively, or a decrease of 51.7 and 25.7% compared with the protected stand. Relationships between VI and FW were, in general, linear for spaced trees and a mixture of linear and non-linear for unspaced trees. On an individual-tree basis, VI:FW relationships were strong at the beginning and end of the spruce budworm outbreak, but weaker in the middle. Combining all years, on a per hectare basis, the relationships between VI and FW were strong (r2 = 0.78 for spaced and 0.80 for unspaced stands), and still held despite defoliation. Fri, 30 Jan 2004 http://cfs.nrcan.gc.ca/publications?id=23798 Growth recovery in young, plantation white spruce following artificial defoliation and pruning http://cfs.nrcan.gc.ca/publications?id=22835 Defoliation by the spruce budworm (Choristoneura fumiferana (Clem.)) was simulated by artificially defoliating trees in a plantation of 12-year-old white spruce (Picea glauca (Moench) Voss) over a 2-year period and then allowing the trees to recover for 3 years. Four treatments were applied: control (C); removal of 50% of the current-year foliage (50); removal of all current-year shoots (100P); and removal of all current-year shoots and some older foliage age-classes (100P+). All treatments increased shoot production. Trees in the 100P treatment completely recovered their foliage mass after 1 year, but trees in the 50 treatment were still affected after 3 years of recovery. Trees in the 100P+ treatment showed poor recovery rates in foliage mass. Only the trees in the 50 treatment completely recovered height growth. After 2 years of defoliation, specific volume increment was reduced by 21.3, 58.1, and 75.3% for the 50, 100P, and 100P+ treatments, respectively. After 3 years of recovery, specific volume increment in the 50 treatment recovered completely, while the 100P and 100P+ treatments were reduced by 34.2 and 79.9%, respectively. Because of the release of suppressed buds following both needle loss only and shoot loss, white spruce may be a reforestation candidate for areas having a high probability of budworm outbreaks. Wed, 01 Oct 2003 http://cfs.nrcan.gc.ca/publications?id=22835 Temporal patterns of balsam fir sawfly defoliation and growth loss in young balsam fir http://cfs.nrcan.gc.ca/publications?id=22837 A 2-year field study was carried out with the balsam fir sawfly, Neodiprion abietis (Harris), on balsam fir, Abies balsamea (L.) Mill., to determine: (1) the temporal patterns of defoliation and foliage weight loss associated with early and late-larval instars; (2) the losses in branch and tree stem volume growth as a result of defoliation by larvae; and (3) the extent to which individual branches are autonomous, and their utility for predicting stem growth losses due to defoliation. In addition, this study also permitted us to determine the relationships between defoliation or foliage weight and branch and tree stem volume growth. Defoliation, foliage weight loss and larval development occurred more quickly in the first year due to warmer temperatures, but final levels of defoliation and foliage weight loss were similar in both years. Cumulative defoliation levels increased from <5% at the beginning of the study to 35 and 63%, respectively, in fall 1999 and 2000. Defoliation was greatest on 1-year-old foliage in both years and most defoliation and foliage weight loss occurred after the initiation of third instar. Based upon individual year-volume increment relationships for each branch and tress, mean volume increment loss in 1999 and 2000, respectively, was 20 and 42% for observation branches and 12 and 35% for tree stems. Similar growth loss estimates of 12 and 46%, respectively, for 1999 and 2000, were obtained when comparing the mean specific volume increment for control and observation branches. Foliage weight after sawfly attack was related to branch and stem volume growth, but defoliation was only related to branch volume loss. Although branch and tree stem growth were strongly related, growth losses in a branch were not related to those in a tree stem. Branch removal and measurement is a practical alternative to cutting trees to estimate stem volume growth in balsam fir. Wed, 01 Oct 2003 http://cfs.nrcan.gc.ca/publications?id=22837 Growth loss and recovery following defoliation by the balsam fir sawfly in young, spaced balsam fir stands http://cfs.nrcan.gc.ca/publications?id=18579 Two stands of intensively managed balsam fir [Abies balsamea (L.) Mill. (Pinaceae)] in western Newfoundland, located with in an area infested by the balsam fir sawfly, Neodiprion abietis (Harr.) (Hymenoptera: Diprionidae) complex, were selected to study growth loss and recovery following severe defoliatin by the balsam fir sawfly in the early 1990s. Four years after the start of the outbreak, volum increments were reduced by 78–81%. The decreased volume increment and recovery coincided well with the balsam fir sawfly outbreak and decline. The growth recovery rates following severe balsam fir sawfly defoliation were slow due to the absence of bud destruction, which triggers the release of suppressed buds, and thus increases foliage production. It is imperative that the severe losses in volume growth caused by balsam fir sawfly defoliation are incorporated into wood supply analyses so that future annual allowable cuts may be adjusted. In addition, to ensure maximum recovery rates at the end of an outbreak, future populations must be kept a a minimum to avoid additional foliage loss. Thu, 18 Oct 2001 http://cfs.nrcan.gc.ca/publications?id=18579 Growth loss and recovery of balsam fir trees following balsam fir sawfly damage http://cfs.nrcan.gc.ca/publications?id=18269 A short overview of research undertaken by Dr. Harald Piene in Newfoundland. Wed, 06 Jun 2001 http://cfs.nrcan.gc.ca/publications?id=18269 Spruce budworm defoliation and growth loss in young balsam fir: patterns of shoot, needle and foliage weight production over a nine-year outbreak cycle http://cfs.nrcan.gc.ca/publications?id=6146 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=6146 Shoot and needle losses in Scots pine: experimental design and techniques for estimating needle biomass of undamaged and damaged branches http://cfs.nrcan.gc.ca/publications?id=6293 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=6293 Spruce budworm defoliation-foliage production: differences between white spruce and balsam fir http://cfs.nrcan.gc.ca/publications?id=6329 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=6329 Changes in spruce budworm defoliation with crown level http://cfs.nrcan.gc.ca/publications?id=6142 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=6142 Spruce budworm defoliation and growth loss in young balsam fir: estimation of volume growth based on stem analysis and increment cores at breast height http://cfs.nrcan.gc.ca/publications?id=6143 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=6143 Spruce budworm defoliation in young balsam fir: the “green” tree phenomenon http://cfs.nrcan.gc.ca/publications?id=6144 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=6144 Spruce budworm defoliation and growth loss in young balsam fir: spacing effects on needlefall in protected trees. http://cfs.nrcan.gc.ca/publications?id=6145 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=6145 Needle survival in young, spaced balsam fir. http://cfs.nrcan.gc.ca/publications?id=6285 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=6285 Spatial and temporal patterns of balsam fir mortality in spaced and unspaced stands caused by spruce budworm defoliation http://cfs.nrcan.gc.ca/publications?id=6109 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=6109 Needle survival in young, spaced balsam fir. http://cfs.nrcan.gc.ca/publications?id=9701 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=9701 Quantifying stand susceptibility and impacts associated with stand and site parameters of white spruce defoliated by the spruce budworm in western Canada http://cfs.nrcan.gc.ca/publications?id=6269 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=6269 Quantifying stand susceptibility, and impacts associated with stand and site parameter, of white spruce defoliated by the spruce budworm in western Canada http://cfs.nrcan.gc.ca/publications?id=9622 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=9622 Spruce budworm defoliation and growth loss in young balsam fir http://cfs.nrcan.gc.ca/publications?id=20190 Wed, 03 Jul 2002 http://cfs.nrcan.gc.ca/publications?id=20190 Analysis of high resolution multispectral MEIS imagery for spruce budworm damage assessment on a single tree basis http://cfs.nrcan.gc.ca/publications?id=6079 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=6079 The sensitivity of young white spruce to spruce budworm defoliation http://cfs.nrcan.gc.ca/publications?id=6141 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=6141 Spruce budworm defoliation and growth loss in young balsam fir: artificial defoliation of potted trees http://cfs.nrcan.gc.ca/publications?id=7370 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7370 Defoliation and growth loss in young balsam fir - the Cape Breton Highlands impact study, 1976-86 http://cfs.nrcan.gc.ca/publications?id=7366 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7366 Spruce budworm defoliation and growth loss in young balsam fir: defoliation in spaced and unspaced stands and individual tree survival http://cfs.nrcan.gc.ca/publications?id=7367 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7367 Spruce budworm defoliation and growth loss in young balsam fir: recovery of growth in spaced stands http://cfs.nrcan.gc.ca/publications?id=7368 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7368 Growth development of young spaced balsam fir stands with different original densities. http://cfs.nrcan.gc.ca/publications?id=8527 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=8527 Defoliation by the spruce budworm - growth loss and recovery of balsam fir trees http://cfs.nrcan.gc.ca/publications?id=8525 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=8525 Growth loss and recovery of balsam fir from spruce budworm defoliation http://cfs.nrcan.gc.ca/publications?id=8526 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=8526 Electrical resistance and capacitance measurements on young spaced and unspaced defoliated and protected balsam fir trees http://cfs.nrcan.gc.ca/publications?id=7369 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7369 An evaluation of growth response of young, spaced balsam fir to 3 years of spruce budworm spraying with Bacillus thuringiensis http://cfs.nrcan.gc.ca/publications?id=7371 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7371 Changes in needle morphology, anatomy, and mineral content during the recovery of protected balsam fir trees initially defoliated by the spruce budworm http://cfs.nrcan.gc.ca/publications?id=7372 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7372 Electrical resistance measurements on young balsam fir trees in relation to specific volume increment, foliar biomass, and ion content of bark and wood http://cfs.nrcan.gc.ca/publications?id=7373 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7373 Variation in balsam fir needle length due to crown position, foliage age, and intertree differences http://cfs.nrcan.gc.ca/publications?id=7276 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7276 Nondestructive estimation of foliar biomass in balsam fir http://cfs.nrcan.gc.ca/publications?id=7365 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7365 Timing of spacing operations in young balsam fir stands http://cfs.nrcan.gc.ca/publications?id=7364 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7364 Snowshoe hare girdling of balsam fir on the Cape Breton Highlands http://cfs.nrcan.gc.ca/publications?id=7747 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7747 Early growth responses to operational spacing in young balsam fir stands on the Cape Breton Highlands, Nova Scotia http://cfs.nrcan.gc.ca/publications?id=7748 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7748 Effects of spruce budworm-caused defoliation on the growth of balsam fir: experimental design and methodology http://cfs.nrcan.gc.ca/publications?id=7751 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7751 Effects of insect defoliation on growth and foliar nutrients of young balsam fir http://cfs.nrcan.gc.ca/publications?id=7363 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7363 Effects of increased spacing on carbon mineralization rates and temperature in a stand of young balsam fir http://cfs.nrcan.gc.ca/publications?id=7362 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7362 Weight loss of litter and cellulose bags in a thinned white spruce forest in interior Alaska http://cfs.nrcan.gc.ca/publications?id=7375 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7375 Relationship between air and ground temperatures in spruce and fir forests http://cfs.nrcan.gc.ca/publications?id=7700 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7700 A low-cost unit for measuring carbon dioxide evolution from organic matter under field conditions http://cfs.nrcan.gc.ca/publications?id=7374 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7374 Factors influencing organic matter decomposition and nutrient turn-over in cleared and spaced, young conifer stands on the Cape Breton Highlands, Nova Scotia http://cfs.nrcan.gc.ca/publications?id=7664 Fri, 21 Jul 2000 http://cfs.nrcan.gc.ca/publications?id=7664