Dacia M. Meneguzzo

Mapping trees outside forests using high-resolution aerial imagery: a comparison of pixel- and object-based classification approaches

Discrete trees and small groups of trees in nonforest settings are considered an essential resource around the world and are collectively referred to as trees outside forests (ToF). ToF provide important functions across the landscape, such as protecting soil and water resources, providing wildlife habitat, and improving farmstead energy efficiency and aesthetics. Despite the significance of ToF, forest and other natural resource inventory programs and geospatial land cover datasets that are available at a national scale do not include comprehensive information regarding ToF in the United States. Additional ground-based data collection and acquisition of specialized imagery to inventory these resources are expensive alternatives. As a potential solution, we identified two remote sensing-based approaches that use free high-resolution aerial imagery from the National Agriculture Imagery Program (NAIP) to map all tree cover in an agriculturally dominant landscape. We compared the results obtained using an unsupervised per-pixel classifier (independent component analysis—[ICA]) and an object-based image analysis (OBIA) procedure in Steele County, Minnesota, USA. Three types of accuracy assessments were used to evaluate how each method performed in terms of: (1) producing a county-level estimate of total tree-covered area, (2) correctly locating tree cover on the ground, and (3) how tree cover patch metrics computed from the classified outputs compared to those delineated by a human photo interpreter. Both approaches were found to be viable for mapping tree cover over a broad spatial extent and could serve to supplement ground-based inventory data. The ICA approach produced an estimate of total tree cover more similar to the photo-interpreted result, but the output from the OBIA method was more realistic in terms of describing the actual observed spatial pattern of tree cover.

Michigan's forests 2004

The first annual inventory of Michigans forests, completed in 2004, covers more than 19.3 million acres of forest land. The data in this report are based on visits to 10,355 forested plots from 2000 to 2004. In addition to detailed information on forest attributes, this report includes data on forest health, biomass, land-use change, and timber-product outputs.

Minnesota's Forests 2008

The second full annual inventory of Minnesotas forests reports 17 million acres of forest land with an average volume of more than 1,000 cubic feet per acre. Forest land is dominated by the aspen forest type, which occupies nearly 30 percent of the total forest land area. Twenty-eight percent of forest land consists of sawtimber, 35 percent poletimber, 35 percent sapling/seedlings, and 2 percent is nonstocked. Additional forest attribute and forest health information is presented along with information on agents of change including changing land use patterns and the introduction of nonnative plants, insects, and disease. Detailed information on forest inventory methods, data quality estimates, and important resource statistics can be found on the Statistics and Quality Assurance DVD included in this report.

Minnesota's forests 1999-2003 (Part A)

The first completed annual inventory of Minnesotas forests reports more than 16.2 million acres of forest land. Additional forest attribute and forest health information is presented along with information on agents of change including changing land use patterns and the introduction of nonnative plants, insects, and diseases.

Indiana's Forests 2008

The second full annual inventory of Indianas forests reports more than 4.75 million acres of forest land with an average volume of more than 2,000 cubic feet per acre. Forest land is dominated by the white oak/red oak/hickory forest type, which occupies nearly a third of the total forest land area. Seventy-six percent of forest land consists of sawtimber, 16 percent contains poletimber, and 8 percent contains sapling/seedlings. The volume of growing stock on timberland has been rising since the 1980s and currently totals more than 8.5 billion cubic feet. The average annual net growth of growing stock on forest land from 2004 to 2008 is approximately 312 million cubic feet per year. This report includes additional information on forest attributes, land use change, carbon, timber products, forest health, and statistics and quality assurance of data collection.

South Dakota's forests 2005

The first completed annual inventory of South Dakotas forests reports almost 1.7 million acres of forest land. Softwood forests make up 74 percent of the total forest land area; the ponderosa pine forest type by itself accounts for 69 percent of the total.

Iowa's Forests 2008

The second full annual inventory of Iowas forests (2004-2008) reports more than 3 million acres of forest land, almost all of which is timberland (98 percent), with an average volume of more than 1,000 cubic feet of growing stock per acre. American elm and eastern hophornbeam are the most numerous tree species, but silver maple and bur oak predominate in terms of live tree volume. Iowas forest land is comprised of 65 percent sawtimber, 19 percent poletimber, and 16 percent sapling/seedling or nonstocked size classes. Average annual net growth of growing-stock trees on Iowas timberland increased during the past decade to the current estimate of nearly 105 million cubic feet. This report includes additional information on forest attributes, land use change, carbon, timber products, and forest health. A DVD included in this report includes 1) descriptive information on methods, statistics, and quality assurance of data collection, 2) a glossary of terms, 3) tables that summarize quality assurance, 4) a core set of tabular estimates for a variety of forest resources, and 5) a Microsoft Access database that represents an archive of data used in this report, with tools that allow users to produce customized estimates.

New Jersey Forests 2013

The second full annual inventory of New Jersey’s forests reports more than 2.0 million acres of forest land and 77 tree species. Forest land is dominated by oak/hickory forest types in the north and pitch pine forest types in the south. The volume of growing stock on timberland has been rising since 1956 and currently totals 3.3 billion cubic feet. Average annual net growth of growing stock from 2008 to 2013 was about 65.7 million cubic feet per year. This report includes additional information on forest attributes, land-use change, carbon, timber products, and forest health. The following information is available online at https://doi.org/10.2737/NRS-RB-109: 1) detailed information on forest inventory statistics, methods, and quality assurance of data collection, 2) a glossary of terms, 3) tables that summarize quality assurance, 4) a core set of tabular estimates for a variety of forest resources, and 5) a Microsoft® Access database that represents an archive of data used in this report, with tools that allow users to produce customized estimates.

Shape indexes for semi-automated detection of windbreaks in thematic tree cover maps from the central United States

Abstract Windbreaks are an important ecological resource across the large expanse of agricultural land in the central United States and are often planted in straight-line or L-shaped configurations to serve specific functions. As high-resolution (i.e.,

Iowa Forests, 2013

The third full annual inventory of Iowas forests (2009-2013) indicates that just under 3 million acres of forest land exists in the State, 81 percent of which is in family forest ownership. Almost all of Iowas forest land is timberland (96 percent), with an average volume of more than 1,000 cubic feet of growing stock per acre on timberland and more than 1,500 cubic feet of all live volume (for trees at least 5 inches diameter at breast height) per acre on timberland. American elm and eastern hophornbeam are the most numerous tree species, but bur oak and silver maple predominate in terms of live-tree volume. Iowas forest land is composed of 70 percent sawtimber, 17 percent poletimber, and 13 percent sapling/seedling or nonstocked size classes. Average annual net growth of growing-stock trees on Iowa’s timberland decreased during the past decade to the current estimate of 71 million cubic feet. This report includes additional information on forest attributes, land-use change, carbon, timber products, wildlife habitat, forest health, and future projections. The following information is available online at http://dx.doi.org/10.2737/NRS-RB-102: 1) descriptive information on methods, statistics, and quality assurance of data collection, 2) a glossary of terms, 3) tables that summarize quality assurance, 4) a core set of tabular estimates for a variety of forest resources, and 5) a Microsoft® Access database that represents an archive of data used in this report, with tools that allow users to produce customized estimates.