scholarly journals Frost Damage in Poplar on the Prairies

1976 ◽  
Vol 52 (2) ◽  
pp. 61-64 ◽  
Author(s):  
Harry Zalasky
Keyword(s):  
Low Temperature ◽  
Frost Damage ◽  
Growth Patterns ◽  
Forest Stands ◽  
Clear Cut ◽  
Mature Forest ◽  
Abscission Layers ◽  
Increment Growth ◽  
Poplar Tree

Frost cankers in poplar are freeze-killed areas of bark and wood around which woody calluses develop and form burls and frost ribs. Frost dieback is a freeze-killed segment of the stem at the base, tip, or mid-portion of a branch or leader. It may or may not enhance natural pruning of poplar branches depending on whether the basal parts are damaged or alive and able to form abscission layers. In addition to abscission, low temperature affects increment, growth patterns, and vigor of poplar. Tree become stunted from persistent leader dieback. Suckers, crooks, and sweeps also characterize many stands of poplar. These characteristics of frost damage in mature forest stands are valuable in assessing the hazard of frost if the stands are to be clear-cut and reforested. The effects of frost damage are controlled somewhat in amenity, parks, and recreational areas because pruning is necessary to prevent wind breakage of staghead and frost-cankered trees.

scholarly journals RESISTANCE TO FROST DAMAGE AT EARLY AGE AND STRENGTH DEVEROPMENT AT LOW-TEMPERATURE ON CONCRETE USING VARIOUS RECYCLING MATERIALS

2009 ◽  
Vol 15 (30) ◽  
pp. 363-366
Author(s):  
Toshiji MIMORI ◽  
Takao TAIRAKU ◽  
Yukio HAMA ◽  
Osamu SENBU
Keyword(s):  
Low Temperature ◽  
Frost Damage ◽  
Early Age

Natural regeneration determines wintering bird presence in wind-damaged coniferous forest stands independent of postdisturbance logging

2015 ◽  
Vol 45 (9) ◽  
pp. 1232-1237 ◽  
Author(s):  
Sinja A.B. Werner ◽  
Jörg Müller ◽  
Marco Heurich ◽  
Simon Thorn
Keyword(s):  
Natural Regeneration ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Economic Value ◽  
Coniferous Forest ◽  
Bird Species ◽  
Forest Stands ◽  
Bird Abundance ◽  
Coniferous Trees ◽  
Mature Forest

Natural disturbances in European production forests are undesired from an economic perspective but are important drivers of biodiversity. The removal of damaged timber to restore economic value is accompanied by negative effects on various species groups, particularly breeding bird communities, and can hinder natural regeneration. However, little is known about the effect of postdisturbance logging on bird assemblages in winter when temperatures are low and food resources are unpredictable. We conducted fixed-radius point counts of wintering birds in forest stands logged or unlogged after windthrows and in mature forest stands to test our predictions that bird species densities and abundances (i) are lower in postdisturbance logged stands and (ii) depend on the amount of natural regeneration, (iii) which differs between logged and unlogged stands. Our generalized linear mixed model did not support the expected differences in bird abundance or species densities between postdisturbance logged and unlogged stands but indicated that mature forest stands harbor the highest bird abundances and species densities. The number of regenerated coniferous trees significantly positively affected wintering bird abundances in both postdisturbance logged and unlogged stands. Hence, the number of coniferous trees appears to be a main predictor of wintering bird presence.

scholarly journals Management Implications of Using Brush Mats for Soil Protection on Machine Operating Trails during Mechanized Cut-to-Length Forest Operations

Forests ◽  
2018 ◽  
Vol 10 (1) ◽  
pp. 19 ◽  
Author(s):  
Eric Labelle ◽  
Dirk Jaeger
Keyword(s):  
Mineral Soil ◽  
Forest Biomass ◽  
Protective Layer ◽  
Timber Harvesting ◽  
Soil Disturbance ◽  
Soil Protection ◽  
Forest Stands ◽  
Forest Operations ◽  
Clear Cut ◽  
Bioenergy Generation

Mechanized cut-to-length forest operations often rely on the use of brush mats created from harvesting debris (tree limbs, tops, and foliage) to reduce soil disturbances as a result of in-stand machine traffic. These brush mats, placed directly on the forest floor within machine operating trails, distribute loads of timber harvesting and extraction machinery to a greater area, thereby reducing peak pressures exerted to the ground and rutting for maintaining technical trafficability of operating trails. Forest biomass has also been promoted as a source of green and renewable energy, to reduce carbon emissions from energy production. However, to maintain sufficient quality of biomass for bioenergy operations (high heating value and low ash content), brush needs to be free of contaminants such as mineral soil. This constraint eliminates the possibility of the dual use of brush, first as a soil protective layer on machine operating trails and afterwards for bioenergy generation. Leaving machine operating trails uncovered will cause machine loads to be fully and directly applied to the soil, thus increasing the likelihood of severe soil disturbance, tree growth impediment and reducing trail trafficability. The main objective of this study was to quantify the effect of varying machine operating trail spacing and width on the amount of brush required for soil protection. This was achieved by creating five model forest stands (four mature and one immature), commonly found in New Brunswick, Canada, and using their characteristics as input in the Biomass Opportunity and Supply Model (BiOS) from FPInnovations. BiOS provided several key biomass related outputs allowing the determination of the amount of biomass available for soil protection, which was the main focus of this research. The simulation results showed that regardless of trail area tested, all four mature forest stands were able to support uniform distribution of 20 kg m−2 brush mats (green mass) throughout their entire trail network during clear-cut operations but not during partial harvests. From the three factors assessed (brush amount, trail width, and trail spacing), trail width had the highest effect on the required brush amount for trail protection, which in turn has a direct impact on the amount of brush that could be used for bioenergy generation.

Sugar-Beet Root Aphid, Pemphigus betae Doane (Homoptera: Aphididae), in Southern Alberta

1963 ◽  
Vol 95 (8) ◽  
pp. 863-873 ◽  
Author(s):  
A. M. Harper
Keyword(s):  
Low Temperature ◽  
Sugar Beet ◽  
Soil Temperature ◽  
Sugar Content ◽  
Beet Root ◽  
Southern Alberta ◽  
Pemphigus Betae ◽  
Sugar Beet Root ◽  
Poplar Tree

AbstractIn southern Alberta the fundatrix of P. betae hatches from the overwintered egg in late April and early May and feeds on an emerging leaf of P. angustifolia or P. balsamifera, forming a gall. In the gall it produces alate fundatrigeniae, which migrate from the poplars to beets and produce apterous alienicolae. This form of the aphid reduces both yield and sugar content of beet roots. During the summer several generations of alienicolae are produced. In the fall most of the alienicolae produce sexuparae. These migrate from beets to poplars, where they produce males and oviparae. Each fertilized ovipara lays a single egg on the bark of a poplar tree. The species may overwinter as eggs on the poplars or as alienicolae in the soil. The egg has an obligatory diapause that is terminated by exposure to low temperature. The fungatrigeniae migrate from late June to mid-August and the sexuparae from early September to late October. The potential reproductive capacities of the fundatrix, fundatrigenia, sexupara, and ovipara averaged 163, 13, 6, and 1, respectively. Under greenhouse conditions 20 aphids (alienicolae) produced 9,000 in 6 weeks when the soil temperature was maintained at 27 °C. Below 15 °C. the rate of reproduction was low and death was caused by exposure to 30 °C. for 6 weeks. The most important predators of P. betae were the anthocorid A. antevolens, the flies S. bigelowi, L. pemphigae and T. glabra, and a coccinellid Scymnus sp.

Community structure of soil oribatida (acari) two years after windthrow in the high tatra mountains

Biologia ◽  
2013 ◽  
Vol 68 (5) ◽  
Author(s):  
Jana Lóšková ◽  
Peter Ľuptáčik ◽  
Dana Miklisová ◽  
Ľubomír Kováč
Keyword(s):  
Species Richness ◽  
Significant Influence ◽  
Spruce Forest ◽  
Forest Stands ◽  
Natural Succession ◽  
Clear Cut ◽  
Lower Abundance ◽  
Natural Development ◽  
Ordination Method ◽  
The Mean

AbstractIn November 2004 a catastrophic windstorm destroyed a large part of the spruce forest in the Tatra National Park (Slovakia). The majority of the windthrown area was cleared; only a small part was left uncleared, thereby allowing regeneration by natural succession. The aim of the present study was to assess the impact of the different forestry practices on soil Oribatida. Three different stands were selected for the study, where sampling took place in June and October 2006: control forest stands (REF), windthrown stands left for natural development (NEX) and clear-cut windthrown stands (EXT). The mean abundance of Oribatida recorded in REF and NEX stands was significantly higher than in EXT stands. Kruskal-Wallis test of mean abundance of adults as well as juveniles confirmed significant influence of treatment and date. The highest abundance of adults was found in control forest stands (REF). Post hoc multiple comparison proved significantly lower abundance of adults in clear-cut stands (EXT) compared with REF. The mean abundance of adults and juveniles was several times higher in stands left for natural development (NEX) than in EXT stands. The highest species richness was observed in REF, followed by NEX and EXT stands. Ordination method showed differences in species composition between studied treatments. Furthermore, a much lower abundance of Hermannia gibba, a dweller of leaf litter and upper soil layers, was recorded in cleared stands compared to the other stands. Indeed, windthrown stands had an obvious lower species richness than control stands. The ordination method used demonstrated a significant influence of both treatment and sampling date on the abundance and species richness of Oribatida. The present study showed that clear-cutting of wind-damaged spruce forest markedly decreases the abundance of soil Oribatida compared with windthrown forest stands left to natural succession.

Development of freezing tolerance in roots and shoots of Scots pine seedlings at nonfreezing temperatures

1998 ◽  
Vol 28 (4) ◽  
pp. 557-565 ◽  
Author(s):  
Aija Ryyppö ◽  
Tapani Repo ◽  
Elina Vapaavuori
Keyword(s):  
Plasma Membrane ◽  
Low Temperature ◽  
Scots Pine ◽  
Fine Roots ◽  
Day Treatment ◽  
Growing Season ◽  
Frost Damage ◽  
Frost Hardiness ◽  
Pine Seedlings ◽  
Extracellular Resistance

The hardening of hydroponically cultured Scots pine (Pinus sylvestris L.) seedlings and their recovery after freezing was studied at the end of the second growing season (LD), after 3 weeks of short day treatment (SD), after a gradual decrease in temperature to 5°C over 4 weeks (H1), and after 4 weeks at 5°C (H2). Frost hardiness was determined by several methods and the recovery as survival of the seedlings. The highest frost hardiness was achieved in the distal parts of needles (-21 to -27°C) and in the proximal parts of needles (-18 to -25°C), followed by woody roots (-7 to -9°C), the 1-year-old and current stem (-8°C), and the fine roots (-5°C), all at the end of H2. Hardening of needles was induced by SD, but the stem and woody roots started to harden later, as a response to low temperature. As a result of frost treatment during LD and SD, potential plasma membrane roman H+-ATPase activity of roots decreased as electrolyte leakage increased and extracellular resistance decreased, but this relationship was lost during H1 and H2. The present study demonstrates the lack of hardening capacity in the fine roots of Scots pine seedlings at nonfreezing temperatures and the increased mortality of the young seedlings having frost damage on roots.

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