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1

Greene, Roger H. "Airborne Video Digital Data for Resource Analysis and Management in the Northeast." Northern Journal of Applied Forestry 5, no. 2 (June 1, 1988): 117–20. http://dx.doi.org/10.1093/njaf/5.2.117.

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Abstract Airborne video data in digital form provides an inexpensive alternative to aerial photography to provide up-to-date information on the size, kinds, and distribution of forest types. Its capability to be incorporated into a geographic information system can augment the value of information produced during analysis. In Maine, Landmark Applied Technologies has developed and is using a system which includes acquiring the video imagery, extracting scenes in digital form, analyzing these data, and incorporating them into an Intergraph GIS to provide a mechanism for rapid updating of spatial data bases. North. J. Appl. For. 5:117-120, June 1988.
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2

Barton, Andrew M., and Daniel J. Grenier. "Dynamics of jack pine at the southern range boundary in downeast Maine." Canadian Journal of Forest Research 38, no. 4 (April 2008): 733–43. http://dx.doi.org/10.1139/x07-176.

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Great Wass Island in Maine supports a large population of Pinus banksiana Lamb. (jack pine) at its southern range boundary. Nearly monospecific stands occur on outcrops and coastal plateau bogs. In contrast to typical populations of this species, six stands exhibited old trees, multiaged structure, and continuous but pulsed establishment despite a lack of widespread fire. Unfavorable soil conditions appear to explain the presence of self-perpetuating populations in this study area, across the geographic range for P. banksiana, and for similar shade-intolerant pine species. Pinus banksiana stands on outcrops exhibited synchronous age structure peaks and included many trees over 150 years old. In contrast, coastal plateau bog stands were younger, were not synchronized in terms of age structure, and contained few large dead trees, suggesting turn-of-the-20th century invasion of these bogs. Analysis of historical aerial photographs furthermore reveals substantial infilling of bogs by P. banksiana since 1940. Although it appears to be an inconsistent and slow process, coastal plateau bog infilling warrants further investigation because of the regional rarity of this ecosystem type.
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3

Small, Erin D., Jeremy S. Wilson, and Alan J. Kimball. "Methodology for the Re-location of Permanent Plot Markers Using Spatial Analysis." Northern Journal of Applied Forestry 24, no. 1 (March 1, 2007): 30–36. http://dx.doi.org/10.1093/njaf/24.1.30.

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Abstract A well-designed method of establishing, maintaining, and remeasuring permanent plots plays an essential role in long-term data collection. This article describes the re-location of plots set up 25 years earlier using conventional techniques of paced distances and compass directions. As a result, we needed to design and use a method for re-locating plot markers originally established without the benefit of spatial coordinates. Preplanned ground searches using a GIS, digital orthophotoquads, landmark maps, and aerial photographs improved our plot location efficiency and success. In 2003, we were able to re-locate 90% of the plots set up in 1978 to measure the vegetation dynamics after a fire in Baxter State Park, Maine. The spatial coordinates of these permanent plots were documented for future measurement. Lessons learned and techniques developed for this project can facilitate the re-location of permanent plots in other studies and can also be used to improve the documentation of newly established plot locations.
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4

Kelly, Kevin. "Determination of Lobster Trap Density near Midcoastal Maine by Aerial Photography." North American Journal of Fisheries Management 13, no. 4 (November 1, 1993): 859–63. http://dx.doi.org/10.1577/1548-8675(1993)013<0859:doltdn>2.3.co;2.

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5

Kamioka, Hisaaki, and Nobuyuki Abe. "Estimating Stand Structure Using Digitalized Aerial Photography." Journal of Forest Research 4, no. 2 (May 1999): 75–78. http://dx.doi.org/10.1007/bf02762229.

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6

Gillis, Mark D., and Donald G. Leckie. "Forest inventory update in Canada." Forestry Chronicle 72, no. 2 (April 1, 1996): 138–56. http://dx.doi.org/10.5558/tfc72138-2.

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Modern forest management presents ever increasing demands for accurate and up-to-date forest inventory information. The process of inventory update is critical. Inventory update in Canada is examined including update for harvest, burns, insect and disease, silviculture, roads and other changes. The magnitude and requirements of the update task are documented. The procedures used are described and summarized by province in table form. Usage, advantages and disadvantages of current methods (e.g. conventional 9 × 9 aerial photography, supplemental aerial photography, satellite imagery, and aerial reconnaissance) are examined, new methods discussed and trends highlighted. Also outlined are issues related to the incorporation of silviculture and insect and disease information into inventories and the structure and responsibilities for update. Key words: forest inventory, inventory update, harvest, burns, insect and disease, blowdown, silviculture, aerial photography, satellite imagery, Global Positioning System, aerial reconnaissance, video
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7

Sypitkowski, Eben, Curtis Bohlen, and William G. Ambrose. "Estimating the frequency and extent of bloodworm digging in Maine from aerial photography." Fisheries Research 101, no. 1-2 (January 2010): 87–93. http://dx.doi.org/10.1016/j.fishres.2009.09.010.

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8

Spencer, Ray D. "Small format aerial photography: methods and achievements in Australian forestry." Australian Forestry 61, no. 4 (January 1998): 267–74. http://dx.doi.org/10.1080/00049158.1998.10674751.

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9

Spencer, R. D. "FILM TRIALS OF AERIAL PHOTOGRAPHY FOR FORESTRY IN VICTORIA, AUSTRALIA." Photogrammetric Record 9, no. 51 (August 26, 2006): 391–403. http://dx.doi.org/10.1111/j.1477-9730.1978.tb00431.x.

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10

Blinn, Charles R., Al Lyons, and Edward R. Buckner. "Color Aerial Photography for Assessing the Need for Fertilizers in Loblolly Pine Plantations." Southern Journal of Applied Forestry 12, no. 4 (November 1, 1988): 270–73. http://dx.doi.org/10.1093/sjaf/12.4.270.

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Abstract Color aerial photography was used to assess crown color classes in loblolly pine (Pinus taeda L.) plantations. Three distinct Munsell color classes were delineated on the resulting photographs. Foliar N levels and, to a lesser degree, foliar K levels were directly related to color. Significant relationships between color and site index and color and basal area were shown. Application of color aerial photography, combined with Munsell color coding, could expedite land classification and also make possible more efficient use of fertilizers. South J. Appl. For. 12(4):270-273.
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11

Williams, Jerry R. "A Private Landowner Perspective of State Policy, Economics and Responsibility in Spruce Budworm Control." Forestry Chronicle 61, no. 5 (October 1, 1985): 388–94. http://dx.doi.org/10.5558/tfc61388-5.

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International Paper Company owns 800 000 acres of timberland in Maine stocked with spruce-fir that has experienced damage from the spruce budworm (Choristoneura fumiferana (Clemens)). Until 1982, these lands were included in the State of Maine-conducted aerial spray protection program. Following changes in state policy and administration, program costs, landowner objectives, and marketing requirements, IP withdrew from the state program to conduct its own program in 1983. Various economic and legal considerations with benefit/cost ratios from protection are described. In addition, the future wood supply is questioned and the state is encouraged to spin off the spray program to the private sector and to concentrate its efforts on resource analysis, insect survey and detection and research.
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12

Fensham, R. J., and R. J. Fairfax. "Assessing woody vegetation cover change in north-west Australian savanna using aerial photography." International Journal of Wildland Fire 12, no. 4 (2003): 359. http://dx.doi.org/10.1071/wf03022.

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Models to calibrate tree and shrub cover assessed from aerial photography with field measurements were developed for a range of vegetation types in north-western Australia. The models verify previous studies indicating that woody cover can be successfully determined from aerial photography. The calibration models were applied to estimates of woody vegetation cover determined for 279 randomly located sample areas in the Ord–Victoria Rivers region using aerial photography from 1948 to 1950 and 1988 to 1997. Overstorey cover increased from a regional average of 11.5% to 13.5% and understorey cover increased from 1.3% to 2.0%. Downs, Limestone Hills and Alluvia land-types showed the most substantial increases in overstorey cover while overstorey cover in the Limestone plains land-type decreased. Relatively open structured vegetation is most susceptible to thickening. Rainfall records reveal an extreme multi-year rainfall deficit in the study area in the 1930s and relatively wet times in the 1970s and 1980s. Interpretation of a limited set of aerial photographs taken between 1964 and 1972 suggests that most of the increases in cover have occurred since this time. The study highlights the possibility that the average trend of vegetation thickening represents recovery during the relatively wet times after the 1970s. There was no relationship between structural change and a grazing intensity surrogate (distance of sample points to stock watering-points). However, the causes of structural change are undoubtedly multi-factored and the relative contributions of climate, fire and grazing vary for different landscapes and tree species.
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13

Fairfax, R. J., and R. J. Fensham. "Corrigendum to: Assessing woody vegetation cover change in north-west Australian savanna using aerial photography." International Journal of Wildland Fire 13, no. 1 (2004): 131. http://dx.doi.org/10.1071/wf03022_co.

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Models to calibrate tree and shrub cover assessed from aerial photography with field measurements were developed for a range of vegetation types in north-western Australia. The models verify previous studies indicating that woody cover can be successfully determined from aerial photography. The calibration models were applied to estimates of woody vegetation cover determined for 279 randomly located sample areas in the Ord–Victoria Rivers region using aerial photography from 1948 to 1950 and 1988 to 1997. Overstorey cover increased from a regional average of 11.5% to 13.5% and understorey cover increased from 1.3% to 2.0%. Downs, Limestone Hills and Alluvia land-types showed the most substantial increases in overstorey cover while overstorey cover in the Limestone plains land-type decreased. Relatively open structured vegetation is most susceptible to thickening. Rainfall records reveal an extreme multi-year rainfall deficit in the study area in the 1930s and relatively wet times in the 1970s and 1980s. Interpretation of a limited set of aerial photographs taken between 1964 and 1972 suggests that most of the increases in cover have occurred since this time. The study highlights the possibility that the average trend of vegetation thickening represents recovery during the relatively wet times after the 1970s. There was no relationship between structural change and a grazing intensity surrogate (distance of sample points to stock watering-points). However, the causes of structural change are undoubtedly multi-factored and the relative contributions of climate, fire and grazing vary for different landscapes and tree species.
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14

Mustonen, Jukka, Petteri Packalén, and Annika Kangas. "Automatic segmentation of forest stands using a canopy height model and aerial photography." Scandinavian Journal of Forest Research 23, no. 6 (December 2008): 534–45. http://dx.doi.org/10.1080/02827580802552446.

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15

Smith, James L., Shepard M. Zedaker, and Richard C. Heer. "Estimating Pine Density and Competition Condition in Young Pine Plantations Using 35mm Aerial Photography." Southern Journal of Applied Forestry 13, no. 3 (August 1, 1989): 107–12. http://dx.doi.org/10.1093/sjaf/13.3.107.

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Abstract A prediction system was developed that estimated pine density and hardwood competition levels in young plantations using simple measurements made on 35mm aerial photographs. The precision of the prediction system was found to be moderate to good. The use of these photo-based modelsin a decision-making situation was examined. Ground-based decisions regarding replanting, spraying for competition control, or no treatment were compared to similar decisions reached strictly from the aerial photographic measurements. Approximately 80% of all decisions agreed, and 90% of theno-treatment decisions agreed. While aerial photographs do not totally eliminate the need for field work, it is clear that photographic information can often produce reliable decisions with reduced field efforts. South. J. Appl. For. 13(3):107-112.
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16

Biggs, P. H., and R. D. Spencer. "New approaches to extensive forest inventory in Western Australia using large-scale aerial photography." Australian Forestry 53, no. 3 (January 1990): 182–93. http://dx.doi.org/10.1080/00049158.1990.10676076.

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17

McTague, John Paul. "Estimation of Stand Density with Probability Proportional to Size from Aerial Photography." Western Journal of Applied Forestry 3, no. 3 (July 1, 1988): 89–92. http://dx.doi.org/10.1093/wjaf/3.3.89.

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18

Hall, R. J., and A. H. Aldred. "Forest regeneration appraisal with large-scale aerial photographs." Forestry Chronicle 68, no. 1 (February 1, 1992): 142–50. http://dx.doi.org/10.5558/tfc68142-1.

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The operational feasibility of using large-scale aerial photographs to quantify coniferous forest stocking and regeneration density, was assessed over 6 cutovers with a 1,700 ha total area. The project involved two stages: one to pre-stratify cutover stocking levels using 1:10,000 general-coverage, colour photos; and the second to sample intensively, stocking and density using 1:500 large-scale photos. The accuracy, cost and practical problems in using large-scale sampling photos for regeneration assessment were determined. Accuracy assessment included detectability of young trees, species interpretation, and reliability of stocking and density measurements. Stocking estimates were on average, only five percent lower than field survey results but could be calibrated using regression techniques. Large differences between field survey and photo estimates of density in stems/ha suggested such counts should not be made from large-scale photos. Density count differences were attributable to seedlings occurring in dense patches or clumps where field counts were also difficult. If survey objectives and methods are carefully planned, large-scale photos can be a suitable tool for assessing and monitoring the stocking and survival rates of coniferous forest regeneration. Key words: Forest regeneration appraisal, silviculture, inventory, sampling, large-scale photography.
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19

Parker, William H., Annette van Niejenhuis, and Laird Van Damme. "Base-line selection of black spruce by large-scale aerial photography." Canadian Journal of Forest Research 18, no. 3 (March 1, 1988): 380–83. http://dx.doi.org/10.1139/x88-056.

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Following selection of black spruce (Piceamariana (Mill.) B.S.P.) for growing space efficiency using a base line of basal area increment vs. crown length × crown radius, the corresponding crown data were determined by large-scale (1:1250) aerial photography for 174 ground-measured trees to determine whether aerial photography would provide a more accurate and cost-effective alternative for plus-tree selection. Values obtained for ground- and photo-measured tree heights and crown lengths corresponded closely, but values of crown radii measured from the ground by a right-angle prism did not correspond in the same manner to values derived from crown horizontal projection areas on the photos. Nonetheless, the different base lines of basal area increments vs. various ground- and photo-measured crown parameters generally identified the same trees as having the greatest growing space efficiency. The inclusion of crown length together with crown radius did not improve the goodness of fit for regressions of basal area increments vs. crown parameters. Apparently, the two horizontal dimensions are adequate to describe growing space for black spruce, perhaps because its crown form is relatively constant. Our results indicate that large-scale aerial photography is well suited to plus-tree selections of black spruce if ground mesurements are not also required to establish base lines; the extra cost of the photos is offset by the greater speed in measuring tree heights or crown horizontal projection areas. Thus, while the technique is sufficiently accurate, it is not cost effective for establishing growing space efficiency base lines where the basal area increment is determined directly from increment cores.
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20

Iqbal, I. A., J. Osborn, C. Stone, A. Lucieer, M. Dell, and C. McCoull. "Evaluating the robustness of point clouds from small format aerial photography over a Pinus radiata plantation." Australian Forestry 81, no. 3 (July 3, 2018): 162–76. http://dx.doi.org/10.1080/00049158.2018.1482799.

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21

Zimmerman, Gregory, F. Wayne Bell, John Woodcock, Aaron Palmer, and Jorma Paloniemi. "Response of Breeding Songbirds to Vegetation Management in Conifer Plantations Established in Boreal Mixedwoods." Forestry Chronicle 87, no. 02 (April 2011): 217–24. http://dx.doi.org/10.5558/tfc2011-009.

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We examined the response of breeding songbird communities 11 years after four vegetation management treatments were applied. Post-treatment vegetation was characterized by manually interpreting large-scale aerial photography and estimating proportional cover of eight vegetation classes. Songbird abundance was assessed by territory mapping. Using GIS layers, number of registrations and average vegetation proportions were compared among treatments. Ordination of the relative abundance of the 11 most frequent bird species suggested differences between Vision® and untreated areas. These results show that effects of vegetation management on songbirds may be more persistent than previous studies suggest and that monitoring should continue.
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22

Morgan, Jessica L., and Sarah E. Gergel. "Automated analysis of aerial photographs and potential for historic forest mapping." Canadian Journal of Forest Research 43, no. 8 (August 2013): 699–710. http://dx.doi.org/10.1139/cjfr-2012-0492.

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Historic information regarding forest status is essential to management and conservation. Manual interpretation of aerial photography has long been the standard for forest inventory; however, manual interpretation can be subjective, inconsistent, and labor-intensive. This research compares automated techniques with manual interpretation results. First, we used an automated process (called segmentation) to delineate homogeneous stands of forests (or objects), analogous to the goal of manually delineating of polygons. Second, we used classification and regression tree (CART) analysis to classify polygons into the forest and terrain schemes used in British Columbia. Most characteristics of objects created via segmentation were similar to manually delineated polygons, as >70% of attributes were statistically similar across local, polygon, and landscape-level comparisons. Using manual interpretations for comparative reference, automated classifications produced overall accuracies ranging from 62% to 86% with per-class accuracies ranging from 0% to 96%. Automated methods yielded classifications meeting provincial overlap accuracy targets and helped identify classifications most suited to automation. Automated procedures have potential for aiding swift utilization of extensive historical photography archives with several caveats for future consideration. While automated techniques may never replicate all aspects of forest inventory classification, automated techniques may be valuable in assisting different phases of the process.
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Biggs, P. H. "Aerial tree volume functions for eucalypts in Western Australia." Canadian Journal of Forest Research 21, no. 12 (December 1, 1991): 1823–28. http://dx.doi.org/10.1139/x91-251.

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Large-scale, fixed-base aerial photography is being used together with ground sampling in a major inventory of eucalypt forest in Western Australia. This paper describes the aerial tree volume functions derived for that inventory, covering species in the jarrah (Eucalyptusmarginata) forest. The equations, derived from ground measurements, predict gross bole volume from estimates of total height and vary with the site quality of the forest. They are used to predict volume from photomeasurements of total height that have been corrected for measurement error. The functions appear suitable for this forest type, although the volumes of veteran trees with severely damaged crowns are underestimated.
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24

Zagalikis, G., A. D. Cameron, and D. R. Miller. "The application of digital photogrammetry and image analysis techniques to derive tree and stand characteristics." Canadian Journal of Forest Research 35, no. 5 (May 1, 2005): 1224–37. http://dx.doi.org/10.1139/x05-030.

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Ground-based forest inventory surveys can provide highly accurate measurements of tree and stand characteristics, but these are expensive to carry out. Aerial photography has been used for several decades as a tool in forest management and inventory. However, conventional methods of interpretation are both time-consuming and costly, with results varying among interpreters. With continuing development of personal computer technology, aerial photographs have become more accessible for digital analysis. This paper presents the potential operational use of digitized aerial photographs for the estimation of tree and stand characteristics of two forest plantations of Sitka spruce (Picea sitchensis (Bong.) Carrière) in Scotland. The digitized aerial photographs were processed using softcopy photogrammetry, and image analysis techniques were used for individual tree crown delineation. For the first site the estimations of stand top height, basal area, volume, biomass, and density (–23.7%) were similar to the ground-measured stand characteristics (±10%), whereas for the second site the estimations were less accurate mainly because of the nonoptimal illumination conditions during the acquisition of the aerial photographs.
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25

Alemdag, I. S. "Estimating ovendry mass of trembling aspen and white birch using measurements from aerial photographs." Canadian Journal of Forest Research 16, no. 1 (February 1, 1986): 163–65. http://dx.doi.org/10.1139/x86-030.

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A pilot study tested the estimation of stem, crown, and whole-tree biomass of single trees from measurements of total tree height and crown area taken from large-scale aerial photographs. The results indicated the feasibility of this method, provided that time of photography is optimal. More extensive testing is required to confirm these encouraging preliminary results.
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26

Arkin, Jeremy, Nicholas C. Coops, Txomin Hermosilla, Lori D. Daniels, and Andrew Plowright. "Integrated fire severity–land cover mapping using very-high-spatial-resolution aerial imagery and point clouds." International Journal of Wildland Fire 28, no. 11 (2019): 840. http://dx.doi.org/10.1071/wf19008.

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Fire severity mapping is conventionally accomplished through the interpretation of aerial photography or the analysis of moderate- to coarse-spatial-resolution pre- and post-fire satellite imagery. Although these methods are well established, there is a demand from both forest managers and fire scientists for higher-spatial-resolution fire severity maps. This study examines the utility of high-spatial-resolution post-fire imagery and digital aerial photogrammetric point clouds acquired from an unmanned aerial vehicle (UAV) to produce integrated fire severity–land cover maps. To accomplish this, a suite of spectral, structural and textural variables was extracted from the UAV-acquired data. Correlation-based feature selection was used to select subsets of variables to be included in random forest classifiers. These classifiers were then used to produce disturbance-based land cover maps at 5- and 1-m spatial resolutions. By analysing maps produced using different variables, the highest-performing spectral, structural and textural variables were identified. The maps were produced with high overall accuracies (5m, 89.5±1.4%; 1m, 85.4±1.5%), with the 1-m classification produced at slightly lower accuracies. This reduction was attributed to the inclusion of four additional classes, which increased the thematic detail enough to outweigh the differences in accuracy.
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Suárez, Juan C., Carlos Ontiveros, Steve Smith, and Stewart Snape. "Use of airborne LiDAR and aerial photography in the estimation of individual tree heights in forestry." Computers & Geosciences 31, no. 2 (March 2005): 253–62. http://dx.doi.org/10.1016/j.cageo.2004.09.015.

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Dell, M., C. Stone, J. Osborn, M. Glen, C. McCoull, A. Rimbawanto, B. Tjahyono, and C. Mohammed. "Detection of necrotic foliage in a young Eucalyptus pellita plantation using unmanned aerial vehicle RGB photography – a demonstration of concept." Australian Forestry 82, no. 2 (April 3, 2019): 79–88. http://dx.doi.org/10.1080/00049158.2019.1621588.

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Ucar, Zennure, Pete Bettinger, Krista Merry, Jacek Siry, J. M. Bowker, and Ramazan Akbulut. "A comparison of two sampling approaches for assessing the urban forest canopy cover from aerial photography." Urban Forestry & Urban Greening 16 (2016): 221–30. http://dx.doi.org/10.1016/j.ufug.2016.03.001.

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Maltamo, M., J. Malinen, P. Packalén, A. Suvanto, and J. Kangas. "Nonparametric estimation of stem volume using airborne laser scanning, aerial photography, and stand-register data." Canadian Journal of Forest Research 36, no. 2 (February 1, 2006): 426–36. http://dx.doi.org/10.1139/x05-246.

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In forest management planning and forestry decision-making there is a continuous need for higher quality information on forest resources. The aim of this study was to improve the quality of forest resource information acquired by airborne laser scanning by combining it with aerial images and current stand-register data. A k-MSN (most similar neighbor) application was constructed for the prediction of the plot and stand volumes of standing trees. The application constructed used various data sources, including laser scanner data, aerial digital photographs, class variables describing a stand, and updated old stand volumes. The ability of these data sources to predict stem volume was tested together and separately. In the airborne laser scanner data based k-MSN application, characteristics of canopy quantiles were used as independent variables. The results show that with respect to individual plot and stand volume estimation approaches, the laser-based technique is a superior one. The results were improved further when other information sources were used together with the laser scanner data. Using a combination of laser scanner data, aerial images, and class variables (on the grounds of the current forest database) improved the root mean square error (RMSE) of the estimated plot volume by 15% (from 16% to 13%) as compared to using laser scanner data on their own. When the results were averaged at the stand level, the accuracy improved considerably, but the use of other information sources together with airborne laser scanner data did not further improve the results as it did at the plot level. The RMSE of stand volume was about 6% in all data combinations where airborne laser scanning information was used. One conclusion is that making use of additional available data sources together with laser material improves the reliability of plot volume estimates. As these additional data typically mean no extra material costs (since they are available in any case), making combined use of these data and laser scanner data improves the cost efficiency of a forest inventory.
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Rodrigues-Eklund, Gabriela, Matthew C. Hansen, Alexandra Tyukavina, Stephen V. Stehman, Klaus Hubacek, and Giovanni Baiocchi. "Sample-Based Estimation of Tree Cover Change in Haiti Using Aerial Photography: Substantial Increase in Tree Cover between 2002 and 2010." Forests 12, no. 9 (September 14, 2021): 1243. http://dx.doi.org/10.3390/f12091243.

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Recent studies have used high resolution imagery to estimate tree cover and changes in natural forest cover in Haiti. However, there is still no rigorous quantification of tree cover change accounting for planted or managed trees, which are very important in Haiti’s farming systems. We estimated net tree cover change, gross loss, and gross gain in Haiti between 2002 and 2010 from a stratified random sample of 400 pixels with a systematic sub-sample of 25 points. Using 30 cm and 1 m resolution images, we classified land cover at each point, with any point touching a woody plant higher than 5 m classified as tree crown. We found a net increase in tree crown cover equivalent to 5.0 ± 2.3% (95% confidence interval) of Haiti’s land area. Gross gains and losses amounted to 9.0 ± 2.1% and 4.0 ± 1.3% of the territory, respectively. These results challenge, for the first time with empirical evidence, the predominant narrative that portrays Haiti as experiencing ongoing forest or tree cover loss. The net gain in tree cover quantified here represents a 35% increase from 2002 to 2010. Further research is needed to determine the drivers of this substantial net gain in tree cover at the national scale.
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Laquerre, Simon, Brian D. Harvey, and Alain Leduc. "Spatial analysis of response of trembling aspen patches to clearcutting in black spruce-dominated stands." Forestry Chronicle 87, no. 1 (February 1, 2011): 77–85. http://dx.doi.org/10.5558/tfc87077-1.

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While expansion of intolerant hardwoods, including trembling aspen, has been recognized as a problem by boreal forestmanagers in eastern Canada, the problem has mostly been associated with the boreal mixedwood and, with a few exceptions,the spatial aspects of the phenomenon have not been well documented in the scientific literature. The objective ofthis study is to evaluate how the density and size of aspen patches influence the change in density, size and persistence ofpatches following clearcutting of black spruce forests in the claybelt region of northwestern Quebec. To do this, we finelyinterpreted: 1) aerial photos taken between 1970 and 1979 of 12 mature black spruce-dominated stands containing varyingsizes and densities of aspen patches prior to being clearcut harvested and 2) aerial photos taken between 1992 and1995 of the 12 resulting clearcuts, 11 to 18 years after harvesting. Sketch maps of pre- and post-harvest aspen presencewere rasterized and changes in aspen patch size and cover were determined. As well, the probabilities of aspen colonizationwith increasing distance from pre-harvest patches were calculated for each site. Black spruce forests of the claybeltcontaining no aspen prior to harvesting are relatively resistant to aspen invasion. However, when forests do contain aspenpatches with cover values ≤25%, almost 60% of these patches increase to a higher density class. Aspen patches less than 2ha in area had about a 50% probability of disappearing following clearcutting whereas larger patches had about a 96%chance of persisting as a result of clearcutting. In the black spruce forest of the claybelt, thick organic layers appear to havea negative effect on aspen recruitment. Distances of regenerating aspen from pre-harvest patches suggest that recruitmentfrom seed is more important than previously thought. Key words: encroachment, trembling aspen, clearcutting, black spruce, claybelt, aerial photography
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Pitt, Douglas G., Robert G. Wagner, Ronald J. Hall, Douglas J. King, Donald G. Leckie, and Ulf Runesson. "Use of remote sensing for forest vegetation management: A problem analysis." Forestry Chronicle 73, no. 4 (August 1, 1997): 459–77. http://dx.doi.org/10.5558/tfc73459-4.

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Forest managers require accurate and timely data that describe vegetation conditions on cutover areas to assess vegetation development and prescribe actions necessary to achieve forest regeneration objectives. Needs for such data are increasing with current emphasis on ecosystem management, escalating silvicultural treatment costs, evolving computer-based decision support tools, and demands for greater accountability. Deficiencies associated with field survey methods of data acquisition (e.g. high costs, subjectivity, and low spatial and temporal coverage) frequently limit decision-making effectiveness. The potential for remotely sensed data to supplement field-collected forest vegetation management data was evaluated in a problem analysis consisting of a comprehensive literature review and consultation with remote sensing and vegetation management experts at a national workshop. Among curently available sensors, aerial photographs appear to offer the most suitable combination of characteristics, including high spatial resolution, stereo coverage, a range of image scales, a variety of film, lens, and camera options, capability for geometric correction, versatility, and moderate cost. A flexible strategy that employs a sequence of 1:10,000-, 1:5,000-, and 1:500-scale aerial photographs is proposed to: 1) accurately map cutover areas, 2) facilitate location-specific prescriptions for silvicultural treatments, sampling, buffer zones, wildlife areas, etc., and 3) monitor and document conditions and activities at specific points during the regeneration period. Surveys that require very detailed information on smaller plants (<0.5-m tall) and/or individual or rare plant species are not likely to be supported by current remote sensing technologies. Recommended areas for research include : 1) digital frame cameras, or other cost-effective digital imagers, as replacements for conventional cameras, 2) computer-based classification and interpretation algorithms for digital image data, 3) relationships between image measures and physical measures, such as leaf-area index and biomass, 4) imaging standards, 5) airborne video, laser altimeters, and radar as complementary sensors, and 6) remote sensing applications in partial cutting systems. Key words: forest vegetation management, regeneration, remote sensing, aerial photography
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34

Tickle, P. K., A. Lee, R. M. Lucas, J. Austin, and C. Witte. "Quantifying Australian forest floristics and structure using small footprint LiDAR and large scale aerial photography." Forest Ecology and Management 223, no. 1-3 (March 2006): 379–94. http://dx.doi.org/10.1016/j.foreco.2005.11.021.

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35

Nandris, D., Tran van Canh, J. P. Geiger, H. Omont, and M. Nicole. "Remote sensing in plant diseases using infrared colour aerial photography: applications trials in the Ivory Coast to root diseases of Hevea brasiliensis." Forest Pathology 15, no. 1 (March 1985): 11–21. http://dx.doi.org/10.1111/j.1439-0329.1985.tb01038.x.

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36

Massada, Avi Bar, Yohay Carmel, Gilad Even Tzur, José M. Grünzweig, and Dan Yakir. "Assessment of temporal changes in aboveground forest tree biomass using aerial photographs and allometric equations." Canadian Journal of Forest Research 36, no. 10 (October 1, 2006): 2585–94. http://dx.doi.org/10.1139/x06-152.

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Studies of forest biomass dynamics typically use long-term forest inventory data, available in only a few places around the world. We present a method that uses photogrammetric measurements from aerial photographs as an alternative to time-series field measurements. We used photogrammetric methods to measure tree height and crown diameter, using four aerial photographs of Yatir Forest, a semi-arid forest in southern Israel, taken between 1978 and 2003. Height and crown-diameter measurements were transformed to biomass using an allometric equation generated from 28 harvested Aleppo pine (Pinus halepensis Mill.) trees. Mean tree biomass increased from 6.37 kg in 1978 to 97.01 kg in 2003. Mean plot biomass in 2003 was 2.48 kg/m2 and aboveground primary productivity over the study period ranged between 0.14 and 0.21 kg/m2 per year. There was systematic overestimation of tree height and systematic underestimation of crown diameter, which was corrected for at all time points between 1978 and 2003. The estimated biomass was significantly related to field-measured biomass, with an R2 value of 0.78. This method may serve as an alternative to field sampling for studies of forest biomass dynamics, assuming that there is sufficient spatial and temporal coverage of the investigated area using high-quality aerial photography, and that the tree tops are distinguishable in the photographs.
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Mast, Joy Nystrom, Thomas T. Veblen, and Michael E. Hodgson. "Tree invasion within a pine/grassland ecotone: an approach with historic aerial photography and GIS modeling." Forest Ecology and Management 93, no. 3 (June 1997): 181–94. http://dx.doi.org/10.1016/s0378-1127(96)03954-0.

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38

Koch, Barbara. "Stand und Perspektiven der Nutzung neuer Fernerkundungstechnologien im Waldbereich | Status and perspectives of the application of new remote sensing technologies in forestry." Schweizerische Zeitschrift fur Forstwesen 162, no. 6 (June 1, 2011): 156–63. http://dx.doi.org/10.3188/szf.2011.0156.

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Remote sensing has been used in forestry for a long time. Aerial photography has mainly been used to support national and operational inventories and medium resolution satellite data for large area inventories. Today through the availability of new technologies there are greatly extended possibilities for remote sensing in the forestry sector. The major change is the better availability of 3-D information, which allows a much better modelling of forests and forest attributes. The paper presents an overview of the newest remote sensing technologies, such as the systems carried by satellite which can be used to record changes or degradation in the area covered by forest for the global forestry resources assessment of the UN World Food and Agriculture Organisation or are examined in connection with the United Nations REDD program. Besides these, other small scale applications are presented based on optical or laser systems carried by aircraft. The article finishes with an outlook on expected developments in the near future. It is expected that the future of forestry remote sensing will be characterized above all by the combination of information obtained from diverse sources, such as data based on terrestrial and on remotely sensed sources.
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Wright, G. G., K. B. Matthews, W. M. Cadell, and R. Milne. "Reducing the cost of multi-spectral remote sensing: combining near-infrared video imagery with colour aerial photography." Computers and Electronics in Agriculture 38, no. 3 (March 2003): 175–98. http://dx.doi.org/10.1016/s0168-1699(02)00141-2.

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40

Grybas, Heather, and Russell G. Congalton. "Evaluating the Capability of Unmanned Aerial System (UAS) Imagery to Detect and Measure the Effects of Edge Influence on Forest Canopy Cover in New England." Forests 12, no. 9 (September 15, 2021): 1252. http://dx.doi.org/10.3390/f12091252.

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Characterizing and measuring the extent of change at forest edges is important for making management decisions, especially in the face of climate change, but is difficult due to the large number of factors that can modify the response. Unmanned aerial systems (UAS) imagery may serve as a tool to detect and measure the forest response at the edge quickly and repeatedly, thus allowing a larger amount of area to be covered with less work. This study is a preliminary attempt to utilize UAS imagery to detect changes in canopy cover, known to exhibit changes due to edge influences, across forest edges in a New England forest. Changes in canopy cover with increasing distance from the forest edge were measured on the ground using digital cover photography and from photogrammetric point clouds and imagery-based maps of canopy gaps produced with UAS imagery. The imagery-based canopy gap products were significantly more similar to ground estimates for canopy cover (p value > 0.05) than the photogrammetric point clouds, but still suffered overestimation (RMSE of 0.088) due to the inability to detect small canopy openings. Both the ground and UAS data were able to detect a decrease in canopy cover to between 45–50 m from the edge, followed by an increase to 100 m. The UAS data had the advantage of a greater sampling intensity and was thus better able to detect a significant edge effect of minimal magnitude effect in the presence of heavy variability.
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Ota, Tetsuji, Oumer S. Ahmed, Sie Thu Minn, Tual Cin Khai, Nobuya Mizoue, and Shigejiro Yoshida. "Estimating selective logging impacts on aboveground biomass in tropical forests using digital aerial photography obtained before and after a logging event from an unmanned aerial vehicle." Forest Ecology and Management 433 (February 2019): 162–69. http://dx.doi.org/10.1016/j.foreco.2018.10.058.

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42

Newton, Michael, Elizabeth C. Cole, Maxwell L. McCormack, and Diane E. White. "Young Spruce-Fir Forests Released by Herbicides II. Conifer Response to Residual Hardwoods and Overstocking." Northern Journal of Applied Forestry 9, no. 4 (December 1, 1992): 130–35. http://dx.doi.org/10.1093/njaf/9.4.130.

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Abstract Responses of conifers and other vegetation to 9 aerial herbicide treatments were evaluated in a replicated conifer-release experiment in a 7-year-old spruce-fir clearcut in central Maine. Development of the naturally regenerated conifers was inversely related to residual hardwood cover and conifer stocking during the 9 years after treatment. All herbicides and rates of application initially reduced hardwood cover by 50% or more. Cover more than 1.5 m tall was nearly eliminated by several treatments, and release from overtopping provided long-term increase in conifer growth. Untreated hardwoods severely reduced dominance and stocking of conifers by age 16. Spruce heights and diameters were less affected by hardwood competition than were those of fir; current growth in released fir was greater than that in released spruce; but unreleased spruce, where present, grew faster than unreleased fir. Conifer growth was affected both by residual hardwood overtopping and by number of conifers within 0.91 m. North. J. Appl. For. 9(4):130-135.
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43

White, Joanne C., Michael A. Wulder, Darin Brooks, Richard Reich, and Roger D. Wheate. "Mapping mountain pine beetle infestation with high spatial resolution satellite imagery." Forestry Chronicle 80, no. 6 (December 1, 2004): 743–45. http://dx.doi.org/10.5558/tfc80743-6.

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The on-going mountain pine beetle outbreak in British Columbia has reached historic proportions. Recently, management efforts at the local level shifted from exhaustive mapping of the infestation, to detection and mitigation of sites with minimal levels of infestation, creating an operational need for efficient and cost-effective methods to identify red-attack trees in these areas. High spatial resolution remotely sensed imagery has the potential to satisfy this information need. This paper presents the unsupervised classification of 4 metre IKONOS multispectral imagery, for the detection of mountain pine beetle red-attack, at sites with minimal infestation (< 20% of trees infested). A 4-metre buffer (analogous to a single IKONOS pixel) was applied to the red-attack trees identified on the IKONOS imagery in order to account for positional errors. When compared to the independent validation data collected from the aerial photography, it was found that 70.1% (lightly infested sites) and 92.5% (moderately infested sites) of the red-attack trees existing on the ground were correctly identified through the classification of the remotely sensed IKONOS imagery. These results demonstrate the operational potential of using an unsupervised classification of IKONOS imagery to detect and map mountain pine beetle red-attack at sites with minimal levels of infestation. Key words: mountain pine beetle, remote sensing, accuracy assessment, IKONOS, red-attack
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44

Wulder, Michael A., Joanne C. White, Allan L. Carroll, and Nicholas C. Coops. "Challenges for the operational detection of mountain pine beetle green attack with remote sensing." Forestry Chronicle 85, no. 1 (January 1, 2009): 32–38. http://dx.doi.org/10.5558/tfc85032-1.

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Mountain pine beetle infestations are spatially correlated; current (green) attack is often located near previous (red) attack. This spatial correlation between the green and red attack stages enables operational survey methods, as detection of red attack trees—typically from an airborne survey such as a helicopter GPS survey or aerial photography—guides the location of subsequent ground surveys for green attack trees. Forest managers, in an attempt to understand beetle movement and infestation patterns, hope to utilize remotely sensed data to detect and map green attack trees, with the expectation that the spatial extent, accuracy, and timeliness afforded by remotely sensed data will greatly improve the efficacy of beetle treatment and control. In this communication, we present the biological, logistical, and technological factors that limit the operational utility of remotely sensed data for green attack detection and mapping. To provide context for these limitations, we identify the operational information needs associated with green attack and discuss how these requirements dictate the characteristics of any potential remotely sensed data source (e.g., spatial, spectral, and temporal characteristics). Based upon our assessment, we conclude that the remote detection of green attack is not operationally viable, and is unlikely to become so unless the limiting factors we have identified are altered substantially or removed. Key words: green attack, remote sensing, operational, insect survey, high spatial resolution, high spectral resolution
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45

Wyckoff, Peter H., and James S. Clark. "Tree growth prediction using size and exposed crown area." Canadian Journal of Forest Research 35, no. 1 (January 1, 2005): 13–20. http://dx.doi.org/10.1139/x04-142.

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We address the relationships between tree growth rate and growing environment for 21 co-occurring species. Tree growth rates are obtained from mapped plots at the Coweeta Long-Term Ecological Research site in the southern Appalachian Mountains. We employ high-resolution aerial photography to assess the light environment for trees growing in these plots, using exposed crown area (ECA) as a surrogate for light interception. The relationship between growth and ECA is compared with two other growth predictors: tree size and shade-tolerance classification. We find that ECA is an excellent predictor of tree growth (average R2 = 0.69 for nine species). When ECA is combined with tree size, growth rate prediction is improved (average R2 = 0.76). Tree size alone is also a strong predictor of tree growth (average R2 = 0.68). Shade-tolerance classification, by contrast, is a poor predictor of tree growth.
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46

Lister, Andrew J., Hans Andersen, Tracey Frescino, Demetrios Gatziolis, Sean Healey, Linda S. Heath, Greg C. Liknes, et al. "Use of Remote Sensing Data to Improve the Efficiency of National Forest Inventories: A Case Study from the United States National Forest Inventory." Forests 11, no. 12 (December 19, 2020): 1364. http://dx.doi.org/10.3390/f11121364.

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Globally, forests are a crucial natural resource, and their sound management is critical for human and ecosystem health and well-being. Efforts to manage forests depend upon reliable data on the status of and trends in forest resources. When these data come from well-designed natural resource monitoring (NRM) systems, decision makers can make science-informed decisions. National forest inventories (NFIs) are a cornerstone of NRM systems, but require capacity and skills to implement. Efficiencies can be gained by incorporating auxiliary information derived from remote sensing (RS) into ground-based forest inventories. However, it can be difficult for countries embarking on NFI development to choose among the various RS integration options, and to develop a harmonized vision of how NFI and RS data can work together to meet monitoring needs. The NFI of the United States, which has been conducted by the USDA Forest Service’s (USFS) Forest Inventory and Analysis (FIA) program for nearly a century, uses RS technology extensively. Here we review the history of the use of RS in FIA, beginning with general background on NFI, FIA, and sampling statistics, followed by a description of the evolution of RS technology usage, beginning with paper aerial photography and ending with present day applications and future directions. The goal of this review is to offer FIA’s experience with NFI-RS integration as a case study for other countries wishing to improve the efficiency of their NFI programs.
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47

Newton, Michael, Elizabeth C. Cole, Diane E. White, and Maxwell L. McCormack. "Young Spruce-Fir Forests Released by Herbicides I. Response of Hardwoods and Shrubs." Northern Journal of Applied Forestry 9, no. 4 (December 1, 1992): 126–30. http://dx.doi.org/10.1093/njaf/9.4.126.

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Abstract Responses of shrubs and hardwoods to 9 aerial herbicide treatments were evaluated in a replicated conifer-release experiment in a 7-year-old spruce-fir clearcut in west-central Maine. All herbicides and rates of application reduced hardwood and shrub cover by 50% or more in year 9, 2 years after treatment. Cover more than 1.5 m tall was nearly eliminated by treatments with triclopyr amine (Garlon 3A®), glyphosate (Roundup®), or a high rate of 2,4,5-T. Phenoxy herbicides (2,4-D and 2,4,5-T) led to short-term reductions in birches, maples, aspen, and raspberry, and little change in willows. Pin cherry was also controlled by these treatments but died out before year 16, regardless of whether it was sprayed. Untreated controls increased in total cover by about 50% between years 7 and 9 and also in abundance of cover >1.5 m tall. Much cover less than 1.5 m tall was left by all treatments other than triclopyr at a high rate. By the 16th year, major differences in height and cover still existed between all treatments and the controls. North. J. Appl. For. 9(4):126-130.
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48

Suziedelyte-Visockiene, Jurate, Arminas Stanionis, Egle Tumeliene, and Ruta Puziene. "Analyses of Archival Cartographic Materials for Geomorphological Changes of River Channel." Advances in Civil Engineering 2018 (July 19, 2018): 1–9. http://dx.doi.org/10.1155/2018/8502780.

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In Lithuania, the old archival topographic maps of locations of small and medium scale and 1 : 10,000 scale contour photo plans were created on the basis of aerial images. The material of these scales provides documented records on the condition of the objects in the location and the landscape at the moment of aerial photography. Those maps can be used to restore the accurate topographic image of the terrain and buildings in 1945–1951 and in later years and perform the necessary topographic, photogrammetric, and geodetic measurements of the parameters of objects, to identify the location of objects and changes. This information is necessary for a variety of disputed property issues and for building farmhouses in reserves, in areas of forestry land parcels, and for assessment of changes in the landscape. Studies of landscape changes are needed for the assessment of renaturalization processes. This paper presents the geodetic method used for geomorphological changes at the channel of River Žalesa during the period 1942–2017, based on the collected archival cartographic materials: historical topographic maps from archive of the Lithuanian State Company Land Fund, Land Information System, and land management projects and orthophoto maps from Lithuanian spatial information portal and free open-access Sentinel-1 satellite data from the Copernicus Open Access Hub.
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Budianti, Noviana, Hiromi Mizunaga, and Atsuhiro Iio. "Crown Structure Explains the Discrepancy in Leaf Phenology Metrics Derived from Ground- and UAV-Based Observations in a Japanese Cool Temperate Deciduous Forest." Forests 12, no. 4 (April 1, 2021): 425. http://dx.doi.org/10.3390/f12040425.

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Unmanned aerial vehicles (UAV) provide a new platform for monitoring crown-level leaf phenology due to the ability to cover a vast area while offering branch-level image resolution. However, below-crown vegetation, e.g., understory vegetation, subcanopy trees, and the branches of neighboring trees, along with the multi-layered structure of the target crown may significantly reduce the accuracy of UAV-based estimates of crown leaf phenology. To test this hypothesis, we compared UAV-derived crown leaf phenology results against those based on ground observations at the individual tree scale for 19 deciduous broad-leaved species (55 individuals in total) characterized by different crown structures. The mean crown-level green chromatic coordinate derived from UAV images poorly explained inter- and intra-species variations in spring leaf phenology, most probably due to the consistently early leaf emergence in the below-crown vegetation. The start dates for leaf expansion and end dates for leaf falling could be estimated with an accuracy of <1-week when the influence of below-crown vegetation was removed from the UAV images through visual interpretation. However, a large discrepancy between the phenological metrics derived from UAV images and ground observations was still found for the end date of leaf expansion (EOE) and start date of leaf falling (SOF). Bayesian modeling revealed that the discrepancy for EOE increased as crown length and volume increased. The crown structure was not found to contribute to the discrepancy in SOF value. Our study provides evidence that crown structure is a pivotal factor to consider when using UAV photography to reliably estimate crown leaf phenology at the individual tree-scale.
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Minnich, RA, and CJ Bahre. "Wildland Fire and Chaparral Succession Along the California Baja-California Boundary." International Journal of Wildland Fire 5, no. 1 (1995): 13. http://dx.doi.org/10.1071/wf9950013.

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The United States-Mexico international boundary from ElPaso, Texas to the Pacific Coast shows clear differences in plant communities that were homogeneous prior to being split by a continuous fence at the turn of the century. This study evaluates how disparate fire regimes in California (fire suppression) and northern Baja California (little or no fire control) have influenced succession in the chamise (Adenostoma fasciculatum) chaparral communities spanning the international boundary between the border towns of Jacume and Tecate. Fire history was reconstructed using U.S. Forest Service fire maps and repeat aerial photography. Once plotted onto topographic maps and dated, the burns were divided into age-classes and sampled using 50 m point-quarter transects to develop successional chronosequences. Although fires are more frequent and smaller on the Mexican side of the border, our repeat photographs of the boundary monument markers together with field samples show that chaparral succession is similar across the international boundary in species composition, stem densities, and average mass shrub height. Chamise chaparral appears to be stable under disparate fire regimes because sprouting habits and latent seed pools permit efficient stand establishment under either short or long fire intervals. Chaparral recovery during the period examined here is unrelated to fire size because recolonization of burns by long-range seed dispersal is not a trait of the majority of the local shrub species and the shrubs either resprout. or germinate from soil seed reservoirs.
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