advertisement

Tian Ostrofsky

50 %
50 %
advertisement
Information about Tian Ostrofsky
Education

Published on January 22, 2008

Author: Sibilla

Source: authorstream.com

advertisement

Slide1:  INTRODUCTION: The above-ground responses of precommercially thinned (PCT) softwood stands have been well studied in comparison with the below-ground responses. As PCT or unthinned (UT) stands mature and become large enough for the first commercial thinning, silvicultural prescriptions must take into consideration factors of stand stability, or wind firmness. Changes in root development and rooting characteristics resulting from PCT have not been documented for stands nearing commercial thinning size. OBJECTIVES: The primary objective of the study is to compare root systems of PCT fir and spruces nearing commercial treatment size, with those in unthinned stands. Rooting characteristics can then be used in models to predict wind firmness. Trees will also be tested directly for rooting strength by winching to simulate windthrow forces. The study will help to answer questions regarding wind firmness of PCT and non-PCT stands following early, or first commercial thinnings, will attempt to quantify root biomass, and will provide information on root and butt decay characteristics and incidence. Work to date has been conducted at the Penobscot Experimental Forest in Bradley, and the townships of T5R18 WELS, and T8R5 WELS, Maine. METHODS: Four 10 X 10 m plots were established in each of a thinned and unthinned stand during the summer of 1998 and 1999. The 30-year-old even-aged stand was precommercially thinned in 1982-1984 to a spacing of 2.44 X 2.44 m (8 X 8 ft). All trees in the plots were mapped, and the five largest spruce along with the five largest fir in each plot were selected for detailed examination. Three 1 X 1 m subplots in each plot were established and excavated for observations of all woody roots present. The entire root system of each selected tree was then hand excavated, and washed free of soil with a high-pressure water sprayer. Root systems were mapped in place, down to a root size of one cm in diameter. The root systems were then excavated completely and brought to a preparation area for final cleaning and detailed measurements. Sample trees were weighed for above-ground total tree biomass in the field. Excavated and cleaned root systems were also weighed for total biomass, using a series of root diameter classes and root structure classes. Decayed roots and stump sections were noted, and are being sampled for identification of pathogens. RECENT RESULTS: Root structure differed greatly between the two species, with balsam fir being more deeply rooted with a more complex and variable rooting structure than red spruce. Balsam fir in the thinned treatment had significantly more (p=0.011) biomass as root dry weight and greater root length (p=0.012) than did tree in the unthinned stands. A similar relationship was not found for spruce, which had no difference in root dry weight or length between thinned and unthinned treatments. When roots were divided into three size classes (1.0-1.9 cm, 2.0-4.9 cm, and 5.0 cm or greater in diameter), balsam fir was found to have a higher proportion of smaller roots, and a lower proportion of larger roots than red spruce. A strong relationship was found between DBH and root weight (r2=0.93) and DBH and root length (r2=0.83) for spruce, and also for balsam fir (r2=0.81 for both relationships). Percentage of crop tree roots decayed was highly variable. No consistent differences were found between thinned and unthinned stands, although balsam fir had a higher percentage of decayed roots than did red spruce. Balsam fir roots also had a significantly greater percentage of decay as root size increased, with 8.7% of small, 19.1% of medium, and 34.4% of large roots decayed. The trend was similar for red spruce roots, which ranged from 1.5% for small roots to 3.8% of large roots decayed. Data on rooting strength based on maximum moment of force required to uproot the trees indicate tree size and species effects, but no significant differences due to thinning treatment. Adding tree height, stem decay, crown size and root plate size to the regression analysis did not improve the relationship between DBH and maximum torque required for uprooting. FUTURE PLANS: In the coming summer we will survey more spruce-fir stands that have been recently precommercially thinned and unthinned to investigate the butt decay incidence. ACKNOWLEDGMENTS: Mr. P. Caron, CFRU Research Associate, provided expertise and assistance throughout the field season. The assistance of J. Brissette and T. Skratt, USDA Forest Service, in locating the site and allowing its use for this study is greatly appreciated. EFFECTS OF PRECOMMERCIAL THINNING ON ROOT STRUCTURE AND ON ROOT AND BUTT DECAY IN YOUNG SPRUCE-FIR STANDS S. Tian, Cooperative Forestry Research Unit, and W.D. Ostrofsky, Department of Forest Management University of Maine, Orono 04469-5755 b Slide2:  INTRODUCTION: The above-ground responses of precommercially thinned (PCT) softwood stands have been well studied in comparison with the below-ground responses. As PCT or unthinned (UT) stands mature and become large enough for the first commercial thinning, silvicultural prescriptions must take into consideration factors of stand stability, or wind firmness. Changes in root development and rooting characteristics resulting from PCT have not been documented for stands nearing commercial thinning size. OBJECTIVES: The primary objective of the study is to compare root systems of PCT fir and spruces nearing commercial treatment size, with those in unthinned stands. Rooting characteristics can then be used in models to predict wind firmness. Trees will also be tested directly for rooting strength by winching to simulate windthrow forces. The study will help to answer questions regarding wind firmness of PCT and non-PCT stands following early, or first commercial thinnings, will attempt to quantify root biomass, and will provide information on root and butt decay characteristics and incidence. Work to date has been conducted at the Penobscot Experimental Forest in Bradley, and the townships of T5R18 WELS, and T8R5 WELS, Maine. METHODS: Four 10 X 10 m plots were established in each of a thinned and unthinned stand during the summer of 1998 and 1999. The 30-year-old even-aged stand was precommercially thinned in 1982-1984 to a spacing of 2.44 X 2.44 m (8 X 8 ft). All trees in the plots were mapped, and the five largest spruce along with the five largest fir in each plot were selected for detailed examination. Three 1 X 1 m subplots in each plot were established and excavated for observations of all woody roots present. The entire root system of each selected tree was then hand excavated, and washed free of soil with a high-pressure water sprayer. Root systems were mapped in place, down to a root size of one cm in diameter. The root systems were then excavated completely and brought to a preparation area for final cleaning and detailed measurements. Sample trees were weighed for above-ground total tree biomass in the field. Excavated and cleaned root systems were also weighed for total biomass, using a series of root diameter classes and root structure classes. Decayed roots and stump sections were noted, and are being sampled for identification of pathogens. RECENT RESULTS: Root structure differed greatly between the two species, with balsam fir being more deeply rooted with a more complex and variable rooting structure than red spruce. Balsam fir in the thinned treatment had significantly more (p=0.011) biomass as root dry weight and greater root length (p=0.012) than did tree in the unthinned stands. A similar relationship was not found for spruce, which had no difference in root dry weight or length between thinned and unthinned treatments. When roots were divided into three size classes (1.0-1.9 cm, 2.0-4.9 cm, and 5.0 cm or greater in diameter), balsam fir was found to have a higher proportion of smaller roots, and a lower proportion of larger roots than red spruce. A strong relationship was found between DBH and root weight (r2=0.93) and DBH and root length (r2=0.83) for spruce, and also for balsam fir (r2=0.81 for both relationships). Percentage of crop tree roots decayed was highly variable. No consistent differences were found between thinned and unthinned stands, although balsam fir had a higher percentage of decayed roots than did red spruce. Balsam fir roots also had a significantly greater percentage of decay as root size increased, with 8.7% of small, 19.1% of medium, and 34.4% of large roots decayed. The trend was similar for red spruce roots, which ranged from 1.5% for small roots to 3.8% of large roots decayed. Data on rooting strength based on maximum moment of force required to uproot the trees indicate tree size and species effects, but no significant differences due to thinning treatment. Adding tree height, stem decay, crown size and root plate size to the regression analysis did not improve the relationship between DBH and maximum torque required for uprooting. FUTURE PLANS: In the coming summer we will survey more spruce-fir stands that have been recently precommercially thinned and unthinned to investigate the butt decay incidence. ACKNOWLEDGMENTS: Mr. P. Caron, CFRU Research Associate, provided expertise and assistance throughout the field season. The assistance of J. Brissette and T. Skratt, USDA Forest Service, in locating the site and allowing its use for this study is greatly appreciated. EFFECTS OF PRECOMMERCIAL THINNING ON ROOT STRUCTURE AND ON ROOT AND BUTT DECAY IN YOUNG SPRUCE-FIR STANDS S. Tian, Cooperative Forestry Research Unit, and W.D. Ostrofsky, Department of Forest Management University of Maine, Orono 04469-5755 b Slide3:  INTRODUCTION: The above-ground responses of precommercially thinned (PCT) softwood stands have been well studied in comparison with the below-ground responses. As PCT or unthinned (UT) stands mature and become large enough for the first commercial thinning, silvicultural prescriptions must take into consideration factors of stand stability, or wind firmness. Changes in root development and rooting characteristics resulting from PCT have not been documented for stands nearing commercial thinning size. OBJECTIVES: The primary objective of the study is to compare root systems of PCT fir and spruces nearing commercial treatment size, with those in unthinned stands. Rooting characteristics can then be used in models to predict wind firmness. Trees will also be tested directly for rooting strength by winching to simulate windthrow forces. The study will help to answer questions regarding wind firmness of PCT and non-PCT stands following early, or first commercial thinnings, will attempt to quantify root biomass, and will provide information on root and butt decay characteristics and incidence. Work to date has been conducted at the Penobscot Experimental Forest in Bradley, and the townships of T5R18 WELS, and T8R5 WELS, Maine. METHODS: Four 10 X 10 m plots were established in each of a thinned and unthinned stand during the summer of 1998 and 1999. The 30-year-old even-aged stand was precommercially thinned in 1982-1984 to a spacing of 2.44 X 2.44 m (8 X 8 ft). All trees in the plots were mapped, and the five largest spruce along with the five largest fir in each plot were selected for detailed examination. Three 1 X 1 m subplots in each plot were established and excavated for observations of all woody roots present. The entire root system of each selected tree was then hand excavated, and washed free of soil with a high-pressure water sprayer. Root systems were mapped in place, down to a root size of one cm in diameter. The root systems were then excavated completely and brought to a preparation area for final cleaning and detailed measurements. Sample trees were weighed for above-ground total tree biomass in the field. Excavated and cleaned root systems were also weighed for total biomass, using a series of root diameter classes and root structure classes. Decayed roots and stump sections were noted, and are being sampled for identification of pathogens. RECENT RESULTS: Root structure differed greatly between the two species, with balsam fir being more deeply rooted with a more complex and variable rooting structure than red spruce. Balsam fir in the thinned treatment had significantly more (p=0.011) biomass as root dry weight and greater root length (p=0.012) than did tree in the unthinned stands. A similar relationship was not found for spruce, which had no difference in root dry weight or length between thinned and unthinned treatments. When roots were divided into three size classes (1.0-1.9 cm, 2.0-4.9 cm, and 5.0 cm or greater in diameter), balsam fir was found to have a higher proportion of smaller roots, and a lower proportion of larger roots than red spruce. A strong relationship was found between DBH and root weight (r2=0.93) and DBH and root length (r2=0.83) for spruce, and also for balsam fir (r2=0.81 for both relationships). Percentage of crop tree roots decayed was highly variable. No consistent differences were found between thinned and unthinned stands, although balsam fir had a higher percentage of decayed roots than did red spruce. Balsam fir roots also had a significantly greater percentage of decay as root size increased, with 8.7% of small, 19.1% of medium, and 34.4% of large roots decayed. The trend was similar for red spruce roots, which ranged from 1.5% for small roots to 3.8% of large roots decayed. Data on rooting strength based on maximum moment of force required to uproot the trees indicate tree size and species effects, but no significant differences due to thinning treatment. Adding tree height, stem decay, crown size and root plate size to the regression analysis did not improve the relationship between DBH and maximum torque required for uprooting. FUTURE PLANS: In the coming summer we will survey more spruce-fir stands that have been recently precommercially thinned and unthinned to investigate the butt decay incidence. ACKNOWLEDGMENTS: Mr. P. Caron, CFRU Research Associate, provided expertise and assistance throughout the field season. The assistance of J. Brissette and T. Skratt, USDA Forest Service, in locating the site and allowing its use for this study is greatly appreciated. EFFECTS OF PRECOMMERCIAL THINNING ON ROOT STRUCTURE AND ON ROOT AND BUTT DECAY IN YOUNG SPRUCE-FIR STANDS S. Tian, Cooperative Forestry Research Unit, and W.D. Ostrofsky, Department of Forest Management University of Maine, Orono 04469-5755 b

Add a comment

Related presentations

Related pages

Chirurgische Therapie von Erkrankungen der ...

Chirurgische Therapie von Erkrankungen der Halswirbelsäule. Priv.-Doz. Dr. T. Pitzen und Dr. Gregor Ostrowski vom SRH Klinikum Karlsbad-Langensteinbach ...
Read more

Christian Ostrowski | Facebook

Christian Ostrowski ist bei Facebook. Tritt Facebook bei, um dich mit Christian Ostrowski und anderen Nutzern, die du kennst, zu vernetzen. Facebook...
Read more

Marcin Ostrowski | LinkedIn

Marcin Ostrowski. Middle East Design Manager at Ischebeck Titan Group - Formwork, Ground Engineering & Concrete Accessories. Location Manchester, Greater ...
Read more

Spiczak Brzeziński (Adelsgeschlecht) – Wikipedia

Modifiziertes Stammwappen beim Grafen Ostrowski (1897) Stammwappen an einem Hausgiebel in Niedersachsen. Eigenes Wappen Die ...
Read more

Profil: Klinikum Karlsbad Langensteinbach

Dr. med. Gregor Ostrowski. Chefarzt. Prof. Dr. med. Tobias Pitzen. Chefarzt. PD Dr. med. Michael Ruf. Chefarzt . Chefarztsekretariat. Telefon: 07202 61-3100
Read more

GTA 5 - Nebenjobs und Freizeit - Kopfgeld-Missionen ...

GTA 5 Komplettlösung und Tipps – So findet und fangt ihr die gesuchten Kautionsflüchtlinge Ostrowski, Tupper, Scoville und Weaver.
Read more

Top 25 Marcin Ostrowski profiles | LinkedIn

View the profiles of professionals named Marcin Ostrowski on LinkedIn. There are 64 professionals named Marcin Ostrowski, who use LinkedIn to exchange ...
Read more

Dan Ostrowski - Google+

Dan Ostrowski - Drama. Since 2011. - Financial Analyst - Hamilton, NJ
Read more

Marcin Ostrowski | LinkedIn

View Marcin Ostrowski's (United Kingdom) professional profile on LinkedIn. LinkedIn is the world's largest business network, helping professionals like ...
Read more