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Silver Spring, MD, United States

Gormally K.H.,University of Maryland University College | Gormally K.H.,Johns Hopkins University | McIntosh M.S.,University of Maryland University College | Mucciardi A.N.,TreeRadar Inc. | McCarty G.W.,U.S. Department of Agriculture
Soil Science Society of America Journal

The morphology and prevalence of macropores < 10 cm in diameter in forested riparian wetlands is largely unknown despite their importance as a mechanism for preferential flow of contaminants to stream channels. Here, we validate field procedures for detecting and mapping the three-dimensional structure of near-surface (15-65 cm deep) lateral macropore networks using non-invasive ground-penetrating radar (GPR) technology at a Mid-Atlantic riparian wetland field study site. Soil core samples used to ground truth the procedures showed that the detection predictions were 92% accurate and tracer dye transmission through the site corroborated the morphology predictions. The results demonstrate the feasibility of using GPR to map preferential flow networks in situ without disturbing environmentally sensitive wetland ecosystems. © Soil Science Society of America. Source

Gormally K.H.,University of Maryland University College | Gormally K.H.,Johns Hopkins University | McIntosh M.S.,University of Maryland University College | Mucciardi A.N.,TreeRadar Inc.
Soil Science Society of America Journal

Preferential flow of water through soil macropores is known to contribute to groundwater and surface water contamination as well as stream bank instability. However, research on the mechanisms and extent of soil macroporosity is limited due to the lack of a practical technique to study macropores in situ without disrupting the site's ecological function. In this paper, we present a ground-penetrating radar (GPR)-based methodology for detecting soil macropores smaller than 10 cm in diameter within 1 m of the soil surface and then creating a computerized tomogram of the macropore network. Manual and automated algorithms for macropore detection were tested for scan data collected using a 900-MHz radar antenna in a field experiment with a silt-loam soil. Buried polyvinyl chloride (PVC) pipes were used to simulate soil macropores of different diameters and fill contents intersected by GPR scan lines at four different angles. Pipes ≥ 3.00 cm in diameter were clearly detectable regardless of the scan line orientation relative to the target, and pipes with diameters as small as 1.85 cm were detected at perpendicular angles of intersection. In a second field experiment, PVC pipes of varying dimensions were buried at different depths to simulate a macropore network of preferential flow pathways. A branch-node algorithm was developed that referenced GPR scan line detections to create an accurate computer-generated three-dimensional map of the pipe network. © Soil Science Society of America. Source

Mucciardi A.N.,TreeRadar Inc. | Luley C.J.,Urban Forestry LLC | Gormally K.H.,Johns Hopkins University
Arboriculture and Urban Forestry

Arborists commonly use sounding during an initial evaluation of urban trees to determine the presence of advanced decay and hollows. Striking the trunk with a mallet produces stress waves that propagate through the wood and, in turn, generate characteristic audible sounds. Successful application of this procedure, however, requires subjective evaluation of the sonic variations that result from different wood species and densities, and various ambient noise conditions. Therefore, a statistical classification approach was developed for automatically identifying decay from stress waves captured using an accelerometer probe that is less subjective and more reproducible than an operator-in-the-loop approach. The classification algorithms were designed to detect the presence of decay from aberrant characteristics of the vibration waveform and do not rely on sonic velocity changes commonly used in most sonic testing for decay. The approach was tested in a preliminary study on 36 segmented trunk samples representing a wide range of typical urban tree species and decay types. The classifier successfully identified the decay status of 83% of the samples independent of species and trunk diameter. The results of this feasibility study cannot be transferred to real world tree inspection without additional testing on standing trees, but do demonstrate the potential of using accelerometers supplemented with a statistical classifier to support an initial assessment of decay in urban trees by an arborist. © 2011 International Society of Arboriculture. Source

Bassuk N.,Cornell University | Grabosky J.,Rutgers University | Mucciardi A.,TreeRadar Inc. | Raffel G.,Dynamic Tree Systems
Arboriculture and Urban Forestry

This study involved locating tree roots with a ground-penetrating radar (GPR) system and then examining excavated roots in the same soil volume to compare the accuracy of the GPR system with true root location. In 2003, Acer platanoides 'Emerald Queen' Norway maples were planted in trenches containing two compacted soils (native silt loam and CU-Structural Soil). The trenches were paved with 10 cm of concrete. In 2008, a GPR system consisting of a 900 MHz antenna mounted on a root-scanning cart was used to conduct linear scans on top of the concrete. Immediately after scanning, the concrete was removed for selected trees and whole root systems were excavated (as an entire system attached to the tree trunk) using an air excavation tool. Regression analysis using mixed effect models showed that the radar reliably predicted root presence in both the native and structural soils. The root count correlations were r 2 = 0.76 and r 2 = 0.81 for the native and structural soils, respectively. In the compacted native soil under concrete, the radar output overestimated the presence of roots at the minimum detection diameter but did provide a signal associated with root presence at this detection level. In the structural soil under concrete, the radar output reliably predicted roots with only slight overestimation. This study showed that GPR data reliably predicted the presence and locations of roots under the concrete pavement in two compacted soils. © 2011 International Society of Arboriculture. Source

TreeRadar Inc. | Date: 2008-09-26

Radar imaging systems for non-invasive assessment of tree and root health, comprised of radars, image processors, software, mobile mounts, carriages, printed instructions and carrying cases, all sold together as a unit. Scientific and technological services, namely, measuring, imaging and analyzing internal and sub-surface wood structure, viability and decay and root masses, and quantitative analysis of tree health and structural integrity.

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