Magistro darbe tiriama galimybė veisti plantacinius želdinius iš svetimžemių eglių rūšių greitam medienos išauginimui Lietuvoje. Darbo tikslas – įvertinti sitkinės eglės (Picea sitchensis), baltosios eglės var. alberta (Picea gauca var. albertiana), raudonosios eglės (Picea rubens), ajaninės eglės (Picea jezoensis), tarprūšinių hibridų – paprastoji eglė x kanadinė eglė (Picea abies x Picea glauca), paprastoji eglė x baltoji eglė (Picea abies x Picea glauca var. albertiana) genotipų tinkamumą sutrumpintos rotacijos plantaciniams želdiniams. Darbo objektas – Rokų Kelmyno bandomieji želdiniai. Darbo metodai ir techninės priemonės – tyrimo metu buvo įvertinti medžių kokybiniai ir kiekybiniai požymiai bandomuosiuose želdiniuose naudojant tokius prietaisus ir metodus: aukštis - aukštimačiu, skersmuo – žerglėmis, kokybiniai požymiai buvo įvertinti pagal vizualaus medžių kokybinių požymių įvertinimo metodiką. Taip pat buvo atlikta šių duomenų statistinė analizė. Naudoti tokie metodai: aprašomosios statistikos rodiklių palyginimas ir tiesinė koreliacinė analizė. Darbo rezultatai. Picea sitchensis ir abu tarprūšiniai hibridai pasižymi didesniu skersmeniu ir aukščiu, taip pat didesniu tūriu, nei vietinė paprastoji eglė. 33 metų amžiuje Picea sitchensis produkuoja 540 m3/ha medienos, kas rodo jos tinkamumą trumpos apyvartos želdiniams. Picea glauda var. albertiana, Picea jezoensis, ir Picea rubens produktyvumas yra mažesnis nei Picea abies. Didžiausiu tiesių ir vienastiebių... [toliau žr. visą tekstą] / This master thesis analyses possibility to cultivate exotic spruce plantations for shorten rotation forestry in Lithuania. Objective of the study was to find out suitability of Picea sitchensis, P. gauca var. albertiana, P. rubens, P. jezoensis, P. abies x P. glauca, P. abies x P. glauca (var. albertiana) for shorten rotation plantations. Object – Roku Kelmyno experimental forest area. Methods – such qualitative and quantitative tree parameters as height, diameter were assessed using clinometer and callipers. Qualitative parameters were assessed using visual tree qualitative parameters assessment methodics. All data was statistically analyzed. Methods used: comparison of descriptive statistics parameters and linear correlation analyzes. The results – Picea sitchensis and both interspecific hybrids have bigger diameter, height and volume parameters than local Norway spruce. Picea sitchensis produce 540 m3/ha of timber in 33 years, it shows suitability for shorten rotation plantations. Productivity of Picea glauda var. albertiana, Picea jezoensis, and Picea rubens is poor compared to Picea abies. Biggest percentage of straight and single-stemed trees were noticed in sitka spruce and both hybrids stands. Yezo spruce had the smallest percentage (62%) of healthy trees. Whereas the other tree species had percentage of healthy trees between 80 and 95. Branches positioned by blunt angle according the steam dominated in all stands and percentage of such trees was from 88 to 100. P... [to full text]

Dendrochronology studies in Atlantic Canada are rare partly because old-growth forests are scarce making it difficult to establish multiple-century tree-ring chronologies. One approach to overcome this problem is to use tree-ring records found in the wood of historical structures. For our study, the Sinclair Inn in Annapolis Royal, Nova Scotia, was selected for a dendroarchaeological assessment because of its rich and complex history: it resulted from the merging of two early 18th Century houses (the Soullard and Skene houses). To date the Sinclair Inn, three other historical structures of a younger age were used to establish an annual ring record in lieu of old-growth forest data. Red spruce (Picea rubens), a dominant tree species in the Maritimes, was the most prominent wood found in the structures and allowed for the creation of a regional red spruce reference chronology extending far enough into the past to cover the supposed period of construction of the Sinclair Inn. Crossdating results indicate cutting dates of 1709 and 1710 for the Skene and Soullard houses, respectively, and 1769 for the inn itself. In the process of dating the structure, a ,200-year long regional floating red spruce chronology (1591–1789) was developed that will further help future dendrochronological investigations in the Maritimes.

<p>Red spruce forests, one of the most critically endangered ecosystems in the United States</p>provides critical habitat for several endemic species or subspecies of the Appalachian Mountains, including the Virginia northern flying squirrel. Once listed as threatened under the Endangered Species Act, the Virginia northern flying squirrel was delisted in 2013. Managers are currently focusing their efforts on projects that increase the extent and connectivity of the squirrel’s habitat through red spruce restoration. At present, there is a paucity of available data to assess the implications of the silvicultural activities associated with red spruce restoration on the movement and occupancy of the Virginia northern flying squirrel. In order to inform management activities, I measured home range, fine-scale habitat use, and estimated detection and occupancy for northern flying squirrels across a gradient of red spruce stands in the Monongahela National Forest. I concluded that home ranges for northern flying squirrels within this region are comprised primarily of red spruce and that northern flying squirrels were selecting larger diameter trees compared to the nearest available neighbor. Additionally, I found that microhabitat characteristics alone did not sufficiently predict northern flying squirrel occupancy and that acoustic methods for surveying northern flying squirrels will require further refinement. Future research efforts should focus on a combination of landscape-level and microhabitat covariates to best predict occupancy of this species across the landscape. Future red spruce management should be approached with caution regarding the potential impact on northern flying squirrel habitat in the short-term. I recommended using spatially-explicit modeling to assess the long-term effects of proposed red spruce restoration projects on northern flying squirrel population demographics, dispersal, and metapopulation connectivity prior to the implementation of silvicultural treatments.

Red spruce (Picea rubens Sarg.) is a commercially and ecologically important conifer species that primarily exists at northern latitudes of eastern North America. During the last glaciation, its range extended down the Appalachian Mountain chain into North Carolina and Tennessee. Since the planet warmed over the subsequent millennia, only small, sky-island populations remain at the highest peaks of the southern Appalachians where their habitat continues to be threatened by a warming climate. While they have been recognized for the rare wildlife habitat they provide in the region, these populations remain understudied. This thesis aimed to provide additional quantitative methods for managing red spruce stands through regionally fitted stem taper equations and to examine differences in stem form between the northern and southern populations of red spruce. In Chapter 1, five stem taper equations were evaluated for their ability to predict upper stem diameters and total volume in southern Appalachian red spruce: a simple linear, a quadratic polynomial, a segmented, a variable exponent, and a geometric model. Based on past studies and our results, we found that the best equations to use were the variable exponent and segmented polynomial models. Users should consider their own objectives and practical limitations in choosing which equation to use. In Chapter 2, we examined differences in stem form using three methods: a sectional rate of change in diameter, a sectional form class ratio, and a region variable added to two taper equations. The results were mixed, with the rates of change showing significant differences (p<0.05), but the form class ratios showing a mix of significant and insignificant differences. The two equations also had contrasting significance results. This made it unclear whether there were significant differences in stem form between the two populations but supported the idea that localized taper equations would provide the best results. / Master of Science / Red spruce (Picea rubens Sarg.) is a conifer native to eastern North America. It primarily exists in cold, moist climates found in the northeastern US and eastern Canada. Additionally, remnant populations of red spruce exist along the highest peaks of the Appalachian Mountains southward into North Carolina and Tennessee. These trees have been separated from northern red spruce populations for thousands of years and subjected to different growing conditions at high elevations that may have affected their stem characteristics. Stem taper is the rate at which the diameter of a tree's stem changes from the ground to the tip. Many equations have been developed to estimate diameters throughout the stem using simple measurements like total height and diameter at breast height (1.37 m or 4.5 ft). These equations can be used to estimate diameters, heights, and volumes of trees which is helpful for valuing trees for wood production, carbon accounting, or wildlife habitat. Stem taper can vary among species and within a species, so tailoring equations to local populations is important for obtaining the most accurate estimates. Currently, there are no known taper equations fitted specifically for these red spruce trees in the southern Appalachians. This thesis aimed to develop stem taper equations specific to this population of trees and to analyze whether the stem forms of southern red spruce trees differed from their northern counterparts. The results showed that there is evidence both for and against the hypothesis that these populations have different stem forms, and further research is necessary to confirm differences. We also showed that a variable exponent equation and a segmented polynomial equation provided the most accurate estimates of diameter and volume for the southern spruce populations.

The Black Mountain range of western North Carolina supports some of the most extensive, but threatened high elevation forests in the southern Appalachians. Of particular note, the insect pathogen, balsam woolly adelgid (Adelges piceae Ratzeburg) has been present on Mt. Mitchell for over fifty years. In anticipation of potential changes in forest composition, vegetation surveys were first conducted in 1966 on nine one-acre plots near the summit of Mt. Mitchell. These plots were re-surveyed in 1978, 1985 and 2002. The purpose of this study was to re-census those plots and use those data to analyze long-term trends in forest composition for fir, spruce-fir, and spruce-fir-hardwood forest types. Since the 1960s and 1970s, all three forest types have experienced a transition away from an understory with a preponderance of Fraser fir (Abies fraseri (Pursh) Poir.) seedlings and saplings, to forests with higher densities of canopy and sub-canopy fir. Canopy red spruce (Picea rubens Sarg.) has similarly increased in density in the fir and spruce-fir types but declined in the spruce-fir-hardwood forest type. In all types, there has been a sharp decline in hardwood seedlings/saplings since a hardwood seedling explosion in 1978. The current analyses indicate that fir and spruce-fir forests have regenerated since the most severe die-offs and that each forest type will experience future impacts from balsam woolly adelgid but these will occur in a non-synchronous pattern.

No description available.