Understory vegetation in northern Ontario jack pine and black spruce plantations: 20-year successional changes

2003 ◽  
Vol 33 (9) ◽  
pp. 1791-1803 ◽  
Author(s):  
Shelley L Hunt ◽  
Andrew M Gordon ◽  
Dave M Morris ◽  
George T Marek
Keyword(s):  
Species Composition ◽  
Environmental Variables ◽  
Black Spruce ◽  
Detrended Correspondence Analysis ◽  
Jack Pine ◽  
Understory Vegetation ◽  
Rate Of Change ◽  
Northern Ontario ◽  
Pine Stands ◽  
Over Time

The 20-year successional development of understory vegetation was investigated in jack pine (Pinus banksiana Lamb.) and black spruce (Picea mariana (Mill.) BSP) plantations in northern Ontario, in relation to stand species composition, species diversity, and the rate of change in stands of different post-disturbance ages. Detrended correspondence analysis (DCA) ordination of plantation stands using species composition data from 1978 and 1998 indicated variation among stands in directions and rates of change in species composition over time. Rank correlations of environmental variables with the DCA axes suggested a light–moisture gradient along the first axis, driven by soil texture and overstory species, and a gradient representing time since disturbance and stand development along the second axis. Although overall beta diversity among stands remained constant over time, some convergence was found among a smaller group of stands, and divergence was noted between spruce and pine stands. Species composition also became more highly correlated with environmental variables through time. From 1978 to 1998, species richness increased in young, dry pine stands; decreased in older, dry pine stands; and decreased in young spruce stands. The understory vegetation in stands on mesic sites was more diverse than that on dry, sandy sites at both times. The rate of change in understory species composition slowed with time after disturbance, indicating an increasing stability in micro en vi ron men tal conditions as the influence of harvesting disturbance became weaker with time.

scholarly journals Aspects of ecological development in managed stands of jack pine and black spruce in northern Ontario: Understory vegetation and nutrient relations

2005 ◽  
Vol 81 (1) ◽  
pp. 61-72 ◽  
Author(s):  
S L Hunt ◽  
A M Gordon ◽  
D M Morris
Keyword(s):  
Species Composition ◽  
Forest Floor ◽  
Black Spruce ◽  
Basal Area ◽  
Jack Pine ◽  
Understory Vegetation ◽  
Northern Ontario ◽  
Nutrient Pools ◽  
Site Type ◽  
Stand Basal Area

This study investigated relationships between understory vegetation and nutrient pools in managed stands of jack pine (Pinus banksiana Lamb.) and black spruce (Picea mariana [Mill.] BSP) in the Lake Nipigon region of northern Ontario. The species composition, biomass, and nutrient pool sizes in the understory vegetation, as well as biomass and nutrient pools in trees and soils, were determined in 16 managed stands ranging in age from 10 to 53 years since establishment and one mature, natural stand. Patterns of above-ground biomass accumulation in understory vegetation varied with overstory tree species and general site type (dry, sandy soils, or mesic, finer-textured soils). Understory vegetation contributed little (0.3 to 2.6%) to total above-ground organic matter (live biomass plus forest floor) but accounted for higher proportions of total above-ground nutrient pools (e.g., 0.7 to 3.4% of N; 3.2 to 11.7% of K) and net primary productivity (1.2 to 21.2%). The species composition of the understory vegetation was strongly related to stand basal area as well as to concentrations of nutrients (N, P, K, Ca, Mg) in the forest floor and mineral soil. The greatest amount of change in vegetation community composition occurred from the pre-to post-canopy closure stages of stand development; fewer differences were observed among stands of a given species and site type 35 to 50 years after establishment. The effects of silvicultural practices were detected in certain stands 35 years after establishment; for example the most severely treated (bladed and thinned) jack pine stand differed from other stands of similar age and soils with its Cladina/Vaccinium-dominated understory, and large amounts of biomass in the moss/lichen stratum. The understory vegetation communities in other managed jack pine stands, by 35 to 50 years, were similar to that of the mature, natural stand, indicating resilience to silvicultural disturbances. Silviculture may have lasting effects on understory vegetation biomass and species composition through its effects on stand basal area, overstory species, and soil nutrients. This research serves as baseline information for further studies into the ecology of managed stands in northern Ontario. Key words: understory, nutrients, managed forests, jack pine, black spruce, canonical correspondence analysis

Hand and Machine Tree Planting in Northern Ontario

1970 ◽  
Vol 46 (6) ◽  
pp. 477-478
Author(s):  
W. C. Stevens
Keyword(s):  
Black Spruce ◽  
Jack Pine ◽  
Tree Planting ◽  
White Pine ◽  
Northern Ontario ◽  
Rock Outcrops ◽  
Important Species ◽  
Precambrian Shield ◽  
Limited Scale ◽  
Commercial Forest

Northern Ontario lies entirely in the Precambrian Shield with its many rock outcrops, sand plains, valleys and extensive lowlands.Tree planting started on a limited scale in Northern Ontario in the 1920's but it was not until the mid-fifties that the program really expanded into millions of trees.White spruce, black spruce, jack pine, red pine and white pine are the most important species planted for commercial forest products.The advent of new site preparation techniques has made possible the planting of areas that were previously by-passed.Due to the rugged conditions in Northern Ontario, tree planting by machine is still not too prevalent.For the purpose of this paper, Northern Ontario is that portion of the province lying north of the historic fur-trading route of the French and Mattawa Rivers and the Great Lakes. The area is made up entirely of Precambrian shield with many outcrops of rock, sand plains of jack pine, valleys and extensive lowlands of spruce.

Individual-tree basal area growth models for jack pine and black spruce in northern Ontario

2004 ◽  
Vol 80 (3) ◽  
pp. 366-374 ◽  
Author(s):  
Lianjun Zhang ◽  
Changhui Peng ◽  
Qinglai Dang
Keyword(s):  
Tree Growth ◽  
Black Spruce ◽  
Basal Area ◽  
Jack Pine ◽  
Mixed Stands ◽  
Northern Ontario ◽  
Individual Tree ◽  
Basal Area Growth ◽  
Wide Range ◽  
Area Growth

Individual-tree models of five-year basal area growth were developed for jack pine (Pinus banksiana Lamb.) and black spruce (Picea mariana (Mill.) BSP) in northern Ontario. Tree growth data were collected from long-term permanent plots of pure and mixed stands of the two species. The models were fitted using mixed model methods due to correlated remeasurements of tree growth over time. Since the data covered a wide range of stand ages, stand conditions and tree sizes, serious heterogeneous variances existed in the data. Therefore, the coefficients of the final models were obtained using weighted regression techniques. The models for the two species were evaluated across 4-cm diameter classes using independent data. The results indicated (1) the models of jack pine and black spruce produced similar prediction errors and biases for intermediate-sized trees (12–28 cm in tree diameter), (2) both models yielded relatively large errors and biases for larger trees (> 28 cm) than those for smaller trees, and (3) the jack pine model produced much larger errors and biases for small-sized trees (< 12 cm) than did the black spruce model. Key words: mixed models, repeated measures, model validation

Insect Attack and Value Loss in Wind-damaged Spruce and Jack Pine Stands in Northern Ontario

1975 ◽  
Vol 5 (3) ◽  
pp. 387-398 ◽  
Author(s):  
Lorne M. Gardiner
Keyword(s):  
Jack Pine ◽  
Northern Ontario ◽  
Extensive Area ◽  
Cold Fronts ◽  
Value Loss ◽  
Pine Trees ◽  
Pine Stands ◽  
Strong Winds ◽  
Wood Boring ◽  
Insect Attack

The forests of northern Ontario are damaged frequently by strong winds that develop along cold fronts. Deterioration of spruce (Picea spp.) and jack pine (Pinusbanksiana Lamb.) saw timber because of wood-boring insects was studied in an extensive area of blowdown between 1969 and 1972. Sawyer beetles (Monochamus spp.) were the most important agents of degrade, but a surprising amount of damage was caused in spruce by Tetropium spp. Broken trees fared worst, but all uprooted trees were heavily attacked by 2 years after the storm. Milling studies showed about a 10% loss in all material combined 1 year after the storm, with the loss in general more than doubling in the 2nd year. The greatest loss occurred in white spruce (Piceaglauca (Moench) Voss), which was of greater original value than jack pine. Trees left standing were not attacked by emerging beetles but were subject to windthrow by relatively light winds. Salvage operations, when desirable, should begin as soon as possible after a blowdown and all stems, including those left standing, should be harvested at once.

Soil organic layer combustion in boreal black spruce and jack pine stands of the Northwest Territories, Canada

2018 ◽  
Vol 27 (2) ◽  
pp. 125 ◽  
Author(s):  
Xanthe J. Walker ◽  
Jennifer L. Baltzer ◽  
Steven G. Cumming ◽  
Nicola J. Day ◽  
Jill F. Johnstone ◽  
...  
Keyword(s):  
Northwest Territories ◽  
Boreal Forests ◽  
Black Spruce ◽  
Jack Pine ◽  
Fire Intensity ◽  
Organic Layer ◽  
Complete Combustion ◽  
Soil Organic Layer ◽  
Pine Stands ◽  
Burn Depth

Increased fire frequency, extent and severity are expected to strongly affect the structure and function of boreal forest ecosystems. In this study, we examined 213 plots in boreal forests dominated by black spruce (Picea mariana) or jack pine (Pinus banksiana) of the Northwest Territories, Canada, after an unprecedentedly large area burned in 2014. Large fire size is associated with high fire intensity and severity, which would manifest as areas with deep burning of the soil organic layer (SOL). Our primary objectives were to estimate burn depth in these fires and then to characterise landscapes vulnerable to deep burning throughout this region. Here we quantify burn depth in black spruce stands using the position of adventitious roots within the soil column, and in jack pine stands using measurements of burned and unburned SOL depths. Using these estimates, we then evaluate how burn depth and the proportion of SOL combusted varies among forest type, ecozone, plot-level moisture and stand density. Our results suggest that most of the SOL was combusted in jack pine stands regardless of plot moisture class, but that black spruce forests experience complete combustion of the SOL only in dry and moderately well-drained landscape positions. The models and calibrations we present in this study should allow future research to more accurately estimate burn depth in Canadian boreal forests.

scholarly journals Bryophyte Conservation in Managed Boreal Landscapes: Fourteen-Year Impacts of Partial Cuts on Epixylic Bryophytes

2021 ◽  
Vol 4 ◽  
Author(s):  
Jeffrey Opoku-Nyame ◽  
Alain Leduc ◽  
Nicole J. Fenton
Keyword(s):  
Species Composition ◽  
Coarse Woody Debris ◽  
Black Spruce ◽  
Woody Debris ◽  
Permanent Plots ◽  
Old Growth ◽  
Clear Cut ◽  
Old Growth Forest ◽  
Old Growth Forests ◽  
Over Time

Clear cut harvest simplifies and eliminates old growth forest structure, negatively impacting biodiversity. Partial cut harvest has been hypothesized (1) to have less impact on biodiversity than clear cut harvest, and (2) to encourage old growth forest structures. Long-term studies are required to test this hypothesis as most studies are conducted soon after harvest. Using epixylic bryophytes as indicators, this study addresses this knowledge gap. Fourteen years after harvest, we examined changes in epixylic bryophyte community composition richness and traits, and their microhabitats (coarse woody debris characteristics and microclimate) along an unharvested, partial cuts and clear cuts harvest treatment in 30 permanent plots established in the boreal black spruce (Picea mariana) forests of northwestern Quebec, Canada. Our results were compared to those of an initial post-harvest study (year 5) and to a chronosequence of old growth forests to examine species changes over time and the similarity of bryophyte communities in partial cut and old growth forests. Coarse woody debris (CWD) volume by decay class varied among harvest treatments with partial cuts and clear cuts recording lower volumes of early decay CWD. The epixylic community was richer in partial cuts than in mature unharvested forests and clear cuts. In addition, species richness and overall abundance doubled in partial and clear cuts between years 5 and 14. Species composition also differed among treatments between years 5 and 14. Furthermore, conditions in partial cut stands supported small, drought sensitive, and old growth confined species that are threatened by conditions in clear cut stands. Lastly, over time, species composition in partial cuts became more similar to old growth forests. Partial cuts reduced harvest impacts by continuing to provide favorable microhabitat conditions that support epixylic bryophytes. Also, partial cut harvest has the potential to encourage old growth species assemblages, which has been a major concern for biodiversity conservation in managed forest landscapes. Our findings support the promotion of partial cut harvest as an effective strategy to achieve species and habitat conservation goals.

Growth and Morphology of Black Spruce, Jack Pine, and White Spruce Container Seedlings in Northern Ontario

1995 ◽  
Vol 12 (2) ◽  
pp. 69-74
Author(s):  
Anneli Jalkanen
Keyword(s):  
Shoot Growth ◽  
Black Spruce ◽  
Growing Season ◽  
White Spruce ◽  
Dry Mass ◽  
Jack Pine ◽  
Northern Ontario ◽  
Morphological Attributes ◽  
Crop Development ◽  
In The Beginning

Abstract The development of morphological attributes of containerized seedlings during the growing season was studied in eight crops from three nurseries in Northern Ontario, including four black spruce crops, three jack pine crops, and one white spruce crop. The variability was proportionally largest in root and shoot dry mass, followed by height and diameter. During seedling growth, proportionally the variability of size did not seem to increase. In absolute scale, however, differences between individual seedlings increased more than differences between seedling trays, possibly due to competition between individuals. Height and shoot growth were greater in the beginning of the growing season, and diameter and root growth were greater toward the end. In comparison to standards, the balance between morphological attributes (height/diameter, shoot/root) was usually acceptable, and usually independent of seedling size. The easiest way of monitoring crop development is to take seedling samples at regular intervals and to construct a growth progression curve for seedling height, if diameter growth reaches acceptable level. Care should be taken that the height of seedlings does not increase too much at the expense of diameter and root development in the larger crops. To monitor this, height-diameter ratios and shoot-root ratios might be measured a couple of times during the growing season to take corrective action if necessary. North. J. Appl. For. 12(2):69-74.

scholarly journals Shelter Spot Seeding Trials with Jack Pine, Black Spruce and White Spruce in Northern Ontario

1986 ◽  
Vol 62 (5) ◽  
pp. 446-450 ◽  
Author(s):  
S. W. J. Dominy ◽  
J. E. Wood
Keyword(s):  
Picea Mariana ◽  
Pinus Banksiana ◽  
Black Spruce ◽  
White Spruce ◽  
Sowing Date ◽  
Jack Pine ◽  
Medium Sand ◽  
Northern Ontario ◽  
Bare Spot ◽  
Height Data

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.

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