A sequential sampling plan was developed to estimate density of sistens of the invasive exotic hemlock woolly adelgid, Adelges tsugae (Annand), by counting adelgids on new shoots of four branch tips sampled from the lower half of the live crown of individual, asymptomatic eastern hemlock trees. The y-intercepts and slopes for the relationship between observed mean and variance of A. tsugae counts were similar for North Carolina and for 2 years of data collected from Virginia; thus, data were pooled to create one regression equation that was used to develop a count-based sequential sampling plan. Validation data sets were obtained in West Virginia and by randomly selecting half of the trees sampled in North Carolina and Virginia, trees not used previously to develop the sampling plan. Validation of the combined North Carolina–Virginia sampling plan showed that the model performed as specified. This plan should allow for estimation of adelgid population changes on a tree over time, provided the tree has not declined due to A. tsugae infestation. This plan can also be used to assess chemical or biological treatment effects on A. tsugae, provided such treatments do not fundamentally alter the mean–variance relationship.
{"title":"A Sequential Sampling Plan for Counts of Adelges tsugae on Individual Eastern Hemlock Trees","authors":"J. Fidgen, D. Legg, S. Salom","doi":"10.5849/SJAF.11-029","DOIUrl":"https://doi.org/10.5849/SJAF.11-029","url":null,"abstract":"A sequential sampling plan was developed to estimate density of sistens of the invasive exotic hemlock woolly adelgid, Adelges tsugae (Annand), by counting adelgids on new shoots of four branch tips sampled from the lower half of the live crown of individual, asymptomatic eastern hemlock trees. The y-intercepts and slopes for the relationship between observed mean and variance of A. tsugae counts were similar for North Carolina and for 2 years of data collected from Virginia; thus, data were pooled to create one regression equation that was used to develop a count-based sequential sampling plan. Validation data sets were obtained in West Virginia and by randomly selecting half of the trees sampled in North Carolina and Virginia, trees not used previously to develop the sampling plan. Validation of the combined North Carolina–Virginia sampling plan showed that the model performed as specified. This plan should allow for estimation of adelgid population changes on a tree over time, provided the tree has not declined due to A. tsugae infestation. This plan can also be used to assess chemical or biological treatment effects on A. tsugae, provided such treatments do not fundamentally alter the mean–variance relationship.","PeriodicalId":51154,"journal":{"name":"Southern Journal of Applied Forestry","volume":"37 1","pages":"75-80"},"PeriodicalIF":0.0,"publicationDate":"2013-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.5849/SJAF.11-029","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70978623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Extending a Model System to Predict Biomass in Mixed-Species Southern Appalachian Hardwood Forests","authors":"Charles O. Sabatia, T. Fox, H. Burkhart","doi":"10.5849/SJAF.12-005","DOIUrl":"https://doi.org/10.5849/SJAF.12-005","url":null,"abstract":"","PeriodicalId":51154,"journal":{"name":"Southern Journal of Applied Forestry","volume":"37 1","pages":"122-126"},"PeriodicalIF":0.0,"publicationDate":"2013-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.5849/SJAF.12-005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70978858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The natural range of shortleaf pine encompasses 22 states from New York to Texas, second only to eastern white pine in the eastern United States. It is a species of minor and varying occurrence in most of these states usually found in association with other pines, but it is the only naturally occurring pine in the northwestern part of its range in Oklahoma, Arkansas, and Missouri. Over the whole of this area, it is apparent that shortleaf pine hybridizes with loblolly pine, including areas of species overlap (sympatry) and nonoverlap (allopatry). In this study, we used 25 DNA markers to measure the levels of hybridization and introgression in populations of juvenile and mature shortleaf pine from a wilderness area within the allopatric range of shortleaf pine that bordered loblolly pine plantings. Frequency of hybrids ranged from 9.2 to 24.0% among the populations sampled, and we found that levels of hybridization correlates with distances to the nearest loblolly pine plantations. However, the rates of hybridization and introgression apparently remained the same among the parent and juvenile populations.
{"title":"Hybridization in naturally regenerated shortleaf pine as affected by the distance to nearby artificially regenerated stands of loblolly pine","authors":"John F. Stewart, C. Tauer, J. Guldin, C. Nelson","doi":"10.5849/SJAF.12-008","DOIUrl":"https://doi.org/10.5849/SJAF.12-008","url":null,"abstract":"The natural range of shortleaf pine encompasses 22 states from New York to Texas, second only to eastern white pine in the eastern United States. It is a species of minor and varying occurrence in most of these states usually found in association with other pines, but it is the only naturally occurring pine in the northwestern part of its range in Oklahoma, Arkansas, and Missouri. Over the whole of this area, it is apparent that shortleaf pine hybridizes with loblolly pine, including areas of species overlap (sympatry) and nonoverlap (allopatry). In this study, we used 25 DNA markers to measure the levels of hybridization and introgression in populations of juvenile and mature shortleaf pine from a wilderness area within the allopatric range of shortleaf pine that bordered loblolly pine plantings. Frequency of hybrids ranged from 9.2 to 24.0% among the populations sampled, and we found that levels of hybridization correlates with distances to the nearest loblolly pine plantations. However, the rates of hybridization and introgression apparently remained the same among the parent and juvenile populations.","PeriodicalId":51154,"journal":{"name":"Southern Journal of Applied Forestry","volume":"37 1","pages":"102-107"},"PeriodicalIF":0.0,"publicationDate":"2013-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.5849/SJAF.12-008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70979005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Relating Quantity, Quality, and Value of Lumber to Planting Density for Loblolly Pine Plantations","authors":"R. Amateis, H. Burkhart","doi":"10.5849/SJAF.12-012","DOIUrl":"https://doi.org/10.5849/SJAF.12-012","url":null,"abstract":"","PeriodicalId":51154,"journal":{"name":"Southern Journal of Applied Forestry","volume":"37 1","pages":"97-101"},"PeriodicalIF":0.0,"publicationDate":"2013-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.5849/SJAF.12-012","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70979056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
fine sandy loam (fine-loamy, siliceous, semiactive, thermic Typic Paleudult) with a slope of 1–10% (Kerr et al. 1980). The other complex (92° 38 W, 31° 8 N at 66 m above sea level) is comprised of Beauregard silt loam and Malbis fine sandy loam (fine-loamy, siliceous, subactive, thermic Plinthic Paleudult) with a slope of 1–5%. Before harvesting, Study 2 was a closed canopy, mature, loblolly pine (P. taeda L.)-hardwood forest. The understory vegetation was mostly hardwood trees, shrubs, and vines and scattered shade tolerant herbaceous plants. The study sites are within the humid, temperate, coastal plain and flatwoods province of the West Gulf Region of the southeastern United States (McNab and Avers 1994). The climate is subtropical. During the 12-year period, December had the lowest average mean temperature of 10.3° C and August had the highest average mean temperature of 28.2° C (National Climatic Data Center 2012). Annual precipitation averaged 1,463 mm with 1,059 mm during the growing season, which included the months of March through November. Both studies are on uplands suitable for restoring longleaf pine forests (Turner et al. 1999). Treatment Establishment In Study 1, the vegetation was rotary mowed and the large woody debris was hand cleared in June 1997. In Study 2, the mature loblolly pine-hardwood forest on both complexes was clearcut harvested in 1996, roller drum chopped, and prescribed fire was applied by October 1997. Primarily grasses dominated the plant community in Study 1, and trees and shrubs dominated the plant community in Study 2 for the next 6 years (Haywood 2005). On plots that were only prescribed burned (checks), 1st-year herbaceous plant mass was 2,058 kg/ha oven-dried weight at Study 1 and 1,055 kg/ha at Study 2. After 4 years, tree and shrub stocking was 18,031 stems/ha with an average total height of 0.06 m and crown width of 0.03 m at Study 1, whereas at Study 2, stocking was 29,270 stems/ha with an average total height of 0.6 m and crown width of 0.3 m. In 1997, four treatments were randomly assigned to the research plots in a randomized complete block design (Steel and Torrie 1980)—check, herbaceous plant control (HPC), woody plant control (WPC), and HPC WPC. In both studies, the 16 research plots (four blocks by four treatments) each measured 22 by 22 m (0.048 ha) and contained 12 rows of 12 seedlings arranged in a 1.83by 1.83-m spacing. The center 64 longleaf pine seedlings (eight rows of eight seedlings each) were the measurement plot. In Study 1, blocking was based on soils with two blocks established on each soil type. In Study 2, blocking was by complex (two blocks on each soil complex) and topographic location within each complex. Longleaf pine seeds from a standard Louisiana seed source were sowed in containers in May 1997. The 28-week-old seedlings were planted on both sites in November 1997 using a planting dibble with a tip of the correct size and shape for the 3.8-cm-wide and 14-cm-deep root plug.
细砂壤土(细壤土，硅质，半活性，热典型的古成年期)，坡度为1-10% (Kerr et al. 1980)。另一个复合体(92°38 W, 31°8 N，海拔66 m)由博勒加德粉砂壤土和马尔比斯细砂壤土(细壤土，硅质，亚活性，热底纪古生代)组成，坡度为1-5%。研究2在采伐前为封闭冠层成熟火炬松阔叶林。林下植被以阔叶树、灌木、藤本植物为主，间或有耐阴草本植物。研究地点位于美国东南部西海湾地区潮湿、温带、沿海平原和平坦森林的省份(McNab和Avers 1994)。这里是亚热带气候。12年期间，12月平均气温最低，为10.3℃，8月平均气温最高，为28.2℃(国家气候数据中心2012)。年平均降水量为1463毫米，生长期(3月至11月)为1059毫米。这两项研究都是在适合恢复长叶松林的高地进行的(Turner et al. 1999)。研究1于1997年6月对植被进行轮作刈割，并对大面积木屑进行人工清除。研究2于1996年采伐两个复区的火炬松-硬木成熟林，1997年10月前进行滚筒式砍伐，并进行规火处理。未来6年，研究1中植物群落以禾本科为主，研究2中以乔灌木为主(Haywood 2005)。在只规定焚烧(检查)的地块上，研究1的一年生草本植物质量为2058公斤/公顷，研究2的一年生草本植物质量为1055公斤/公顷。4年后，研究1的乔灌木蓄积量为18,031茎/ha，平均总高0.06 m，冠宽0.03 m，而研究2的蓄积量为29,270茎/ha，平均总高0.6 m，冠宽0.3 m。1997年，采用随机完全区组设计(Steel and Torrie 1980)，将4个处理随机分配到研究地块，分别为对照、草本植物对照(HPC)、木本植物对照(WPC)和HPC WPC。在这两项研究中，16块研究地块(4块4个处理)每块面积为22 × 22米(0.048公顷)，包含12行12棵幼苗，以1.83 × 1.83米的间距排列。中心64株长叶松苗(每行8株)为测量样地。在研究1中，拦阻是基于土壤的，每种土壤类型建立两个拦阻。在研究2中，通过复合体(每个土壤复合体上有两个地块)和每个复合体内的地形位置进行阻塞。1997年5月，来自路易斯安那州标准种子源的长叶松种子在容器中播种。这些28周大的树苗于1997年11月在两个地点种植，苗尖的大小和形状都与3.8厘米宽、14厘米深的根塞吻合。HPC采用两种除草剂:乙氧基(2-[1(乙氧基亚胺)丁基]-5-[2-(乙基硫基)丙基]-3-羟基-2-环己烯-1- 1)用于防治蓝茎草，hexazinone(3 -环己基-6-[二甲氨基]-1-甲基-1,3,5-三嗪-2,4[1H, 3H]-二酮)用于防治一般草本植物。研究1于1998年4月和1999年4月在长叶松幼苗行上以0.9 m波段施用两种除草剂。在0.9 m波段内，乙氧基肟和己嗪酮的有效成分含量分别为0.37 kg /ha和1.12 kg /ha。在研究2中，1998年4月和1999年4月，由于不需要乙氧基啶防治蓝茎草，只使用了己嗪酮。在这两项研究中，WPC都是用0.0048 kg酸当量/升的三氯吡啶([(3,5,6 -三氯-2-吡啶基)氧]乙酸进行的。1998年4月，将三氯吡虫啉与表面活性剂和水罐式混合，作为定向叶面喷雾剂施用于阔叶树和灌木。研究2在1999年6月进行了退耕，但研究1不需要退耕，因为1999年5月早些时候的一场大火将大部分木本植被顶灭。在2001年2月的两项研究中，回收的灌木都是手工砍伐的。在这两项研究中，作为一种正常的管理实践，常规地使用了规定的火。消防厅消防管理人员为了确保各场所或建筑物的边界，首先设置了逆火。然后，消防队员会用滴灌火炬或使用直升机上的点火系统点火，直到整个地点或建筑群被烧毁。研究1在1999年5月(种植后18个月)、2001年4月、2003年5月、2005年6月、2007年6月和2009年5月使用了规定的火。这六起火灾都是强烈的，这在成熟的草地上很常见(Haywood 2009, 2011)。在研究2中，第一次规定的火灾推迟到2000年6月(种植后31个月)，因为缺乏草的发育和随后的燃料床条件差。 2003年1月的一场野火烧毁了3号和4号街区，但长叶松幸免于难，因为这种物种通常能承受高强度的火灾(Haywood 2009, 2011)。另外两座楼宇则在二零零三年五月以订明火灭火。接下来的三场火灾分别发生在2005年5月、2007年6月和2009年5月。在7岁和12岁时对长叶松的总高度和胸径进行测量。7岁时用校准杆测量身高，12岁时用激光仪器(standard 400 Survey laser, laser Technology, Inc.， Centennial, CO .)测量身高。用直径卷尺测量树径。采用Baldwin和Saucier(1983)的计算公式，采用总高度和胸径计算外树皮孔体积。在第13个生长季节的9月，估计凋落物和林下植被的覆盖百分比为五种不同的紫杉草、牧草(包括禾本科植物和蕨类植物)、乔木、灌木(包括黑莓)和木本藤本植物。测量是在5个1.83 × 1.83米的正方形上进行的，这些正方形的角是长叶松幼苗的原始种植位置。每个地块的中间和每四分之一地块的中心都有一个广场。在每项研究中，采用随机完全区组设计模型(SAS Institute, Inc.， 1985)，比较四种处理的每公顷长叶松数、平均总高、每棵树的基面积和容积以及每公顷的基面积和容积。分析比较了7岁和12岁时的处理以及5年期间生长和产量的差异。用相同的模型对第13个生长期凋落物盖度进行了分析。对林下植被盖度的分析采用协方差分析模型，其中乔灌木盖度的协变量为第四季乔灌木盖度。对于木本藤本，协变量为第四个生长期每公顷的藤本数。对于草和牧草，协变量为南方。j:。对。研究1的第三生长期和研究2的第四个生长期盖度均为100%。如四种处理间有显著差异，采用Tukey 's Studentized Range Test进行均值比较，0.05。在分析之前对百分比进行反正弦变换以平衡方差(Steel和Torrie 1980)。在研究1中，经过7个生长季节后，HPC、WPC地块上的长叶松总高度显著大于对照和WPC地块(表1)。处理组合也使长叶松的基面积和单株体积大于对照。12个生长季后，处理组合的松树总高高于对照。4个处理间12年树龄基材面积和单株体积变化无显著性差异，5年总高、基材面积和单株体积变化无显著性差异。12年后，高枝样地的总高度从7 ~ 8 m不等，每棵树的基材面积从0.6 ~ 0.7 dm不等，每棵树的体积从25 ~ 34 dm不等。在研究2中，长叶松的总高、基材面积和单株体积在7个生长季节后显著高于对照和普通样地，并且在7个生长季节后，普通样地的总高大于普通样地(表1)。在12岁时，普通样地的总高大于普通样地，处理组合的基材面积和单株体积均大于普通样地。在5年期间，每棵树的基材面积变化在检查大于在HPC样地。12年后，HPC样地的总高度从11 m到12 m不等，每棵树的基底面积从1.2 dm到1.4 dm不等，每棵树的体积从69 dm到85 dm不等。在两项研究中，12个生长季节后的长叶松放养均未受到植后
{"title":"Effects of herbaceous and woody plant control on longleaf pine growth and understory plant cover","authors":"J. Haywood","doi":"10.5849/SJAF.11-045","DOIUrl":"https://doi.org/10.5849/SJAF.11-045","url":null,"abstract":"fine sandy loam (fine-loamy, siliceous, semiactive, thermic Typic Paleudult) with a slope of 1–10% (Kerr et al. 1980). The other complex (92° 38 W, 31° 8 N at 66 m above sea level) is comprised of Beauregard silt loam and Malbis fine sandy loam (fine-loamy, siliceous, subactive, thermic Plinthic Paleudult) with a slope of 1–5%. Before harvesting, Study 2 was a closed canopy, mature, loblolly pine (P. taeda L.)-hardwood forest. The understory vegetation was mostly hardwood trees, shrubs, and vines and scattered shade tolerant herbaceous plants. The study sites are within the humid, temperate, coastal plain and flatwoods province of the West Gulf Region of the southeastern United States (McNab and Avers 1994). The climate is subtropical. During the 12-year period, December had the lowest average mean temperature of 10.3° C and August had the highest average mean temperature of 28.2° C (National Climatic Data Center 2012). Annual precipitation averaged 1,463 mm with 1,059 mm during the growing season, which included the months of March through November. Both studies are on uplands suitable for restoring longleaf pine forests (Turner et al. 1999). Treatment Establishment In Study 1, the vegetation was rotary mowed and the large woody debris was hand cleared in June 1997. In Study 2, the mature loblolly pine-hardwood forest on both complexes was clearcut harvested in 1996, roller drum chopped, and prescribed fire was applied by October 1997. Primarily grasses dominated the plant community in Study 1, and trees and shrubs dominated the plant community in Study 2 for the next 6 years (Haywood 2005). On plots that were only prescribed burned (checks), 1st-year herbaceous plant mass was 2,058 kg/ha oven-dried weight at Study 1 and 1,055 kg/ha at Study 2. After 4 years, tree and shrub stocking was 18,031 stems/ha with an average total height of 0.06 m and crown width of 0.03 m at Study 1, whereas at Study 2, stocking was 29,270 stems/ha with an average total height of 0.6 m and crown width of 0.3 m. In 1997, four treatments were randomly assigned to the research plots in a randomized complete block design (Steel and Torrie 1980)—check, herbaceous plant control (HPC), woody plant control (WPC), and HPC WPC. In both studies, the 16 research plots (four blocks by four treatments) each measured 22 by 22 m (0.048 ha) and contained 12 rows of 12 seedlings arranged in a 1.83by 1.83-m spacing. The center 64 longleaf pine seedlings (eight rows of eight seedlings each) were the measurement plot. In Study 1, blocking was based on soils with two blocks established on each soil type. In Study 2, blocking was by complex (two blocks on each soil complex) and topographic location within each complex. Longleaf pine seeds from a standard Louisiana seed source were sowed in containers in May 1997. The 28-week-old seedlings were planted on both sites in November 1997 using a planting dibble with a tip of the correct size and shape for the 3.8-cm-wide and 14-cm-deep root plug.","PeriodicalId":51154,"journal":{"name":"Southern Journal of Applied Forestry","volume":"37 1","pages":"108-112"},"PeriodicalIF":0.0,"publicationDate":"2013-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.5849/SJAF.11-045","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70978969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Survival and Juvenile Growth of Loblolly and a Pitch x Loblolly Pine Hybrid in West-Central Arkansas","authors":"D. Burner","doi":"10.5849/SJAF.11-035","DOIUrl":"https://doi.org/10.5849/SJAF.11-035","url":null,"abstract":"","PeriodicalId":51154,"journal":{"name":"Southern Journal of Applied Forestry","volume":"37 1","pages":"59-62"},"PeriodicalIF":0.0,"publicationDate":"2013-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.5849/SJAF.11-035","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70978729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
density (Gingrich 1967, Lanner 1985). A site index curve is developed by plotting height and age data for a given species and forming a height-age growth curve (Avery 1975). A series of harmonized curves is then plotted, usually at 10-ft intervals at the base age, to generate a series of anamorphic site index curves (Schnur 1937). Users can then plot tree height and age data collected from the stand onto species-specific curves and determine site index. Husch et al. (1982) reinforced that site index varies according to species on a given site and that site index curves are prepared for individual species. Furthermore, index trees, or the trees from which total height and age are measured, were not suppressed from an overstory canopy during their lifetime; otherwise, the productive potential of the site for a particular species would be underestimated. Several problems exist when using index trees for site index determination. Spurr and Barnes (1980) noted that assigning dominant and codominant crown classes to individual trees for site index determination is subjective and not necessarily repeatable, though Meadows et al. (2001) developed a crown classification system to quantify bottomland hardwood tree crowns on the basis of crown position and condition. Furthermore, tree canopy status changes over time as individuals drop from a dominant or codominant crown class to lower crown classes through competition, reducing the repeatability of measuring the same index trees (Raulier et al. 2003). Determining tree heights accurately also may be difficult because of dense leaf layers in tree tops during the growing season. McNab (1989) noted that age is particularly difficult to measure accurately in hardwoods. Furthermore, questions arise as to how many index trees are needed to accurately determine site index (Mailly et al. 2004). Finally, there is a temptation to use site index curves beyond the range of data used to develop the height-age relationships. Additional problems have been noted using anamorphic site index curves (Tesch 1980). First, an assumption is made in developing anamorphic curves that height development of a species is similar across a variety of age classes and site conditions. Many authors have showed this to not be true (e.g., Carmean 1956, 1972, Hilt and Dale 1982). Curtis (1964) and Carmean (1972) indicated that harvesting was more likely to occur on good sites than poor sites because trees would reach merchantable size earlier on good sites. Therefore, older age classes in site index curve development would mostly be represented by trees growing on poor sites. Second, Carmean (1972) found different patterns of height growth for upland oak species, based on stem analysis data, compared with height development based on anamorphic site index curves; therefore, he used polymorphic height growth patterns to better explain differences in height growth within a species. Anamorphic site index curves are proportional curves that have a
密度(金里奇1967，兰纳1985)。通过绘制给定物种的高度和年龄数据并形成高度-年龄生长曲线来开发站点指数曲线(Avery 1975)。然后绘制一系列协调曲线，通常在基准年龄以10英尺的间隔绘制，以生成一系列变形站点指数曲线(Schnur 1937)。然后，用户可以将收集到的树木高度和年龄数据绘制到特定物种的曲线上，并确定站点指数。Husch et al.(1982)强调，在给定的地点，不同的物种会有不同的地点指数，而地点指数曲线是为单个物种准备的。此外，指数树，即测量总高度和树龄的树木，在其一生中不会受到上层冠层的抑制;否则，该地点对某一特定物种的生产潜力将被低估。在使用索引树确定站点索引时存在几个问题。Spurr和Barnes(1980)指出，为单个树木分配优势和共优势树冠类别以确定场地指数是主观的，不一定可重复，尽管Meadows等人(2001)开发了一个树冠分类系统，根据树冠位置和条件量化洼地硬木树冠。此外，树冠状态随着时间的推移而变化，个体通过竞争从优势或共优势树冠类下降到较低的树冠类，降低了测量相同指数树的可重复性(Raulier等，2003)。由于生长季节树顶的叶子层很密，所以准确地确定树高也很困难。McNab(1989)指出，硬木的年龄尤其难以准确测量。此外，问题是需要多少索引树才能准确确定站点索引(Mailly et al. 2004)。最后，人们倾向于使用超出用于发展高度-年龄关系的数据范围的站点指数曲线。使用变形位点指数曲线(Tesch 1980)还注意到其他问题。首先，在发展变形曲线时，假设一个物种的高度发育在不同的年龄和地点条件下是相似的。许多作者已经证明这是不正确的(例如，Carmean 1956, 1972, Hilt and Dale 1982)。Curtis(1964)和Carmean(1972)指出，在好地点比差地点更有可能采伐，因为在好地点，树木会更早达到可销售的大小。因此，在站点指数曲线发展中，年龄较大的类别将主要由生长在较差站点上的树木来代表。其次，Carmean(1972)基于树干分析数据发现了陆地栎树种高度生长的不同模式，并将其与基于变形立地指数曲线的高度发育进行了比较;因此，他使用多态高度生长模式来更好地解释物种内高度生长的差异。变形站点指数曲线是比例曲线，无论树龄如何，高度之间的比例都是恒定的(Carmean 1972)。多态位点指数曲线不成比例;因此，他们将有不同的身高比例取决于年龄的高度比较。例如，Carmean(1972)表明，黑栎(Quercus velutina Lam.)在后期的高度生长差异取决于场地质量。这些差异不会出现在变形位点指数曲线中，但它们确实出现在多态性位点指数曲线中。Carmean et al.(1989)发表了一组最全面的硬木立地指数曲线，共有31个种或种群的53条曲线。表1列出了所有已知的南方洼地阔叶树种立地指数曲线。其他的曲线可用于这些物种中的一些，但是为美国南部以外的地区开发的。在现有的9个物种的16个站点指数曲线中，只有3个是1976年以后发表的。Clatterbuck(1987)发表了樱桃栎(Quercus pagoda Raf.)和枫香(Liquidambar styraciflua L.)的立地指数曲线，作为旧田洪泛区立地发展研究的一部分，Cao和Durand(1991)发表了生长在密西西比河下游冲积河谷的东部棉木人工林的立地指数曲线。南方滩地阔叶树种立地指数信息少的原因有四个方面。首先，网站指数曲线的开发是昂贵的。需要相当大的努力来定位符合立地指数确定假设的林分:相对未受干扰的、平均年龄的林分。其次，海拔的微小变化强烈影响洪水、沉积、土壤质地和土壤ph。这些变化强烈影响物种组成和生产力(Hodges 1997; Wall and Darwin 1999)，使立地指数的确定变得困难。 第三，滥伐高等级等采伐行为极大地改变了低地阔叶林，导致适合指数树的林分很少。最后，由于堤坝/道路建设和城市发展导致的水期变化导致了洼地场址的不断变化，使场址指数成为一个流动的而不是静态的值。立地指数曲线仍将是确定立地指数的最常用技术，这是文献和森林管理人员培训中公认的一种措施。此外，在今天的许多增长和产量模型中，场地指数是一个关键变量(Hilt 1985)。然而，森林管理者必须意识到使用场地指数曲线的局限性。土壤-立地指数方程土壤-立地指数方程提供了一种定量的方法来估算基于土壤和立地变量的立地指数，这些变量直接或间接地影响树木的生长。变量可能包括表土的深度，土壤质地，有无平底锅，地形和地形。已经发表了几篇基于旧文献的土壤场地指数方程的综述(Carmean 1975,1977)。建立了几种阔叶树在旱地和洼地的土壤立地指数方程。由指数曲线确定的立地指数与旱地阔叶树方程的相关性(r 0.61 ~ 0.86)大于旱地阔叶树方程(r 0.38 ~ 0.68)，这主要是因为旱地阔叶树对立地指数的影响较大。南方洼地阔叶树种立地指数曲线(Francis 1984年更新)。物种来源地区(州)引用美国梧桐女士,电话和Ferrill (1958) Cherrybark橡树AR,洛杉矶,MS, TN布罗德富特Clatterbuck女士(1961)(1987)东部杨木,在肯塔基州,密苏里州Neebe博伊斯(1959)基于“增大化现实”技术,肯塔基州,洛杉矶,MS, TN布罗德富特(1960),亚历山大女士(1976)曹女士和杜兰(1991)绿灰AR,洛杉矶,MS, TN布罗德富特(1969)Nuttall橡树AR,洛杉矶,MS, TN布罗德富特(1969)沼泽blackgum GA Applequist(1959)枫香,FL, MS, SC的冬季和奥斯本(1935)基于“增大化现实”技术,洛杉矶,女士,TN Broadfoot和Krinard (1959) AL Lyle等人(1975)MS Clatterbuck (1987) Water tupelo GA Applequist (1959) Water oak AR, AL, LA, MS, TN Broadfoot(1963)和Nyssa biflora Walt。b Nyssa aquatica L. 6 SOUTH。j:。对。37(1) 2013坡度位置和坡向对高地树高生长的影响(例如，Trimble 1964, Graney 1977, Woolery et al. 2002)。由于地势相对平坦，地势对洼地的影响较小。然而，Beaufait(1956)发现，仅仅几英寸的海拔差异就会强烈影响粉土和粘土含量、洪水深度和持续时间以及土壤通气性，从而将这些地形特征与场地指数联系起来。Broadfoot(1969)反对在洼地阔叶林中使用土壤立地指数方程，特别是出于投资目的。由于洼地土壤的高度变异性，以及一些土壤属性(如化学性质)难以在野外测量，这些方程几乎没有实际应用价值。土壤-场地方程确实可以更好地理解各种土壤和场地特征对树高生长的影响。例如，Broadfoot(1969)开发了以下水栎(Quercus nigra L.)的立地指数方程:SI50 87.11 13.34(X1) 1.5
{"title":"Site index determination techniques for southern bottomland hardwoods","authors":"B. Lockhart","doi":"10.5849/SJAF.09-027","DOIUrl":"https://doi.org/10.5849/SJAF.09-027","url":null,"abstract":"density (Gingrich 1967, Lanner 1985). A site index curve is developed by plotting height and age data for a given species and forming a height-age growth curve (Avery 1975). A series of harmonized curves is then plotted, usually at 10-ft intervals at the base age, to generate a series of anamorphic site index curves (Schnur 1937). Users can then plot tree height and age data collected from the stand onto species-specific curves and determine site index. Husch et al. (1982) reinforced that site index varies according to species on a given site and that site index curves are prepared for individual species. Furthermore, index trees, or the trees from which total height and age are measured, were not suppressed from an overstory canopy during their lifetime; otherwise, the productive potential of the site for a particular species would be underestimated. Several problems exist when using index trees for site index determination. Spurr and Barnes (1980) noted that assigning dominant and codominant crown classes to individual trees for site index determination is subjective and not necessarily repeatable, though Meadows et al. (2001) developed a crown classification system to quantify bottomland hardwood tree crowns on the basis of crown position and condition. Furthermore, tree canopy status changes over time as individuals drop from a dominant or codominant crown class to lower crown classes through competition, reducing the repeatability of measuring the same index trees (Raulier et al. 2003). Determining tree heights accurately also may be difficult because of dense leaf layers in tree tops during the growing season. McNab (1989) noted that age is particularly difficult to measure accurately in hardwoods. Furthermore, questions arise as to how many index trees are needed to accurately determine site index (Mailly et al. 2004). Finally, there is a temptation to use site index curves beyond the range of data used to develop the height-age relationships. Additional problems have been noted using anamorphic site index curves (Tesch 1980). First, an assumption is made in developing anamorphic curves that height development of a species is similar across a variety of age classes and site conditions. Many authors have showed this to not be true (e.g., Carmean 1956, 1972, Hilt and Dale 1982). Curtis (1964) and Carmean (1972) indicated that harvesting was more likely to occur on good sites than poor sites because trees would reach merchantable size earlier on good sites. Therefore, older age classes in site index curve development would mostly be represented by trees growing on poor sites. Second, Carmean (1972) found different patterns of height growth for upland oak species, based on stem analysis data, compared with height development based on anamorphic site index curves; therefore, he used polymorphic height growth patterns to better explain differences in height growth within a species. Anamorphic site index curves are proportional curves that have a","PeriodicalId":51154,"journal":{"name":"Southern Journal of Applied Forestry","volume":"37 1","pages":"5-12"},"PeriodicalIF":0.0,"publicationDate":"2013-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.5849/SJAF.09-027","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70978236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Witt, C. Barton, J. Stringer, D. Bowker, R. Kolka
{"title":"Evaluating Best Management Practices for Ephemeral Stream Protection following Forest Harvest in the Cumberland Plateau","authors":"E. Witt, C. Barton, J. Stringer, D. Bowker, R. Kolka","doi":"10.5849/SJAF.11-041","DOIUrl":"https://doi.org/10.5849/SJAF.11-041","url":null,"abstract":"","PeriodicalId":51154,"journal":{"name":"Southern Journal of Applied Forestry","volume":"37 1","pages":"36-44"},"PeriodicalIF":0.0,"publicationDate":"2013-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.5849/SJAF.11-041","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70978781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. M. Secoges, W. Aust, J. Seiler, C. A. Dolloff, W. Lakel
Forestry best management practices (BMP) recommendations for streamside management zones (SMZs) are based on limited data regarding SMZ width, partial harvests, and nutrient movements after forest fertilization. Agricultural fertilization is commonly linked to increased stream nutrients. However, less is known about effectiveness of SMZ options for controlling nutrient movements after silvicultural fertilization. Diammonium phosphate and urea were applied to 12 subwatersheds in 3-year-old loblolly pine (Pinus taeda L.) plantations in the Virginia Piedmont. Three replicates of four SMZ treatments were superimposed on 12 subwatersheds in a previous SMZ harvest sediment study (7.6-m SMZ, 15.2-m SMZ thin, 15.2-m SMZ, and 30.5-m SMZ). Surface, near-surface, subsurface, and stream water samples were collected monthly for 1 year and analyzed for nitrate (NO3 ), ammonium (NH4 ), and orthophosphate (ortho-P). Transected measurements from streamside to fertilized plantations allowed interpretations of spatial nutrient measurements across SMZs. When compared with wider SMZs, 7.6-m SMZs had 3–10 surface water NO3 ,3 – 6 near-surface water NO3 , and 1–2 more stream water NO3 . No significant differences were detected for NH 4 for any SMZ treatment. The 15.2-m SMZ thin had small but significant increases (2– 8) in surface runoff for ortho-P relative to other SMZ treatments, perhaps because of increased surface water movement along thinning corridors. Across all SMZ treatments, comparisons of stream edges with fertilized stands indicated NO3 reductions of 33–98%, NH4 reductions of 68 –97%, and ortho-P reductions of 70 –98%. A 39% rainfall deficit during the study influenced results, but conventional SMZs 15.2 m protected streams from fertilization nutrient increases.
关于河滨管理区(SMZs)的林业最佳管理实践(BMP)建议是基于关于河滨管理区宽度、部分收成和森林施肥后养分流动的有限数据。农业施肥通常与河流养分增加有关。然而，对于SMZ方案在造林施肥后控制养分运动的有效性知之甚少。对弗吉尼亚山前山地区3年生火炬松人工林12个流域施用磷酸二铵和尿素。在之前的SMZ收获沉积物研究中，在12个子流域(7.6 m SMZ、15.2 m SMZ薄、15.2 m SMZ和30.5 m SMZ)叠加了4个SMZ处理的3个重复。每月收集地表、近地表、地下和溪流水样，分析硝酸盐(NO3)、铵(NH4)和正磷酸盐(orthp)。从河滨到施肥人工林的横切测量可以解释跨smz的空间营养测量。与较宽的SMZs相比，7.6 m SMZs的地表水NO3含量为3 - 10，近地表水NO3含量为3 - 6，溪流NO3含量为1-2。在任何SMZ处理中，nh4均未检测到显著差异。15.2 m薄层土壤地表径流的正磷含量较其他处理增加了2 ~ 8个百分点，这可能是由于沿变薄廊道的地表水运动增加所致。在所有SMZ处理中，河流边缘与施肥林分的比较表明，NO3减少33-98%，NH4减少68 -97%，正磷减少70 -98%。研究期间39%的降雨不足影响了结果，但常规的SMZs 15.2 m保护了溪流免受施肥养分增加的影响。
{"title":"Streamside Management Zones Affect Movement of Silvicultural Nitrogen and Phosphorus Fertilizers to Piedmont Streams","authors":"J. M. Secoges, W. Aust, J. Seiler, C. A. Dolloff, W. Lakel","doi":"10.5849/SJAF.11-032","DOIUrl":"https://doi.org/10.5849/SJAF.11-032","url":null,"abstract":"Forestry best management practices (BMP) recommendations for streamside management zones (SMZs) are based on limited data regarding SMZ width, partial harvests, and nutrient movements after forest fertilization. Agricultural fertilization is commonly linked to increased stream nutrients. However, less is known about effectiveness of SMZ options for controlling nutrient movements after silvicultural fertilization. Diammonium phosphate and urea were applied to 12 subwatersheds in 3-year-old loblolly pine (Pinus taeda L.) plantations in the Virginia Piedmont. Three replicates of four SMZ treatments were superimposed on 12 subwatersheds in a previous SMZ harvest sediment study (7.6-m SMZ, 15.2-m SMZ thin, 15.2-m SMZ, and 30.5-m SMZ). Surface, near-surface, subsurface, and stream water samples were collected monthly for 1 year and analyzed for nitrate (NO3 ), ammonium (NH4 ), and orthophosphate (ortho-P). Transected measurements from streamside to fertilized plantations allowed interpretations of spatial nutrient measurements across SMZs. When compared with wider SMZs, 7.6-m SMZs had 3–10 surface water NO3 ,3 – 6 near-surface water NO3 , and 1–2 more stream water NO3 . No significant differences were detected for NH 4 for any SMZ treatment. The 15.2-m SMZ thin had small but significant increases (2– 8) in surface runoff for ortho-P relative to other SMZ treatments, perhaps because of increased surface water movement along thinning corridors. Across all SMZ treatments, comparisons of stream edges with fertilized stands indicated NO3 reductions of 33–98%, NH4 reductions of 68 –97%, and ortho-P reductions of 70 –98%. A 39% rainfall deficit during the study influenced results, but conventional SMZs 15.2 m protected streams from fertilization nutrient increases.","PeriodicalId":51154,"journal":{"name":"Southern Journal of Applied Forestry","volume":"37 1","pages":"26-35"},"PeriodicalIF":0.0,"publicationDate":"2013-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.5849/SJAF.11-032","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70978658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Engber, J. Varner, Christopher J. Dugaw, Lenya Quinn-Davidson, J. Hiers
14 Duff fires have been implicated in overstory mortality and soil heating in long-unburned pine 15 forests. In the South’s punctuated climate, duff moisture can change rapidly, falling below 16 moisture thresholds that protect trees or increasing following brief downpours. To date, 17 managers lack an instantaneous measure of duff moisture, a hurdle to the implementation of 18 prescribed burns. Here we evaluate a low-cost tool, the Campbell Scientific Duff Moisture Meter 19 (DMM) 600, to estimate duff moisture content in the field. Comparisons of the DMM 600 20 outputs with paired oven-dried duff fuel samples revealed statistically significant differences, 21 with DMM 600 moisture output explaining 54 percent of the variation in oven-dried moisture 22 content. Comparisons with previously published data demonstrate that large variations in duff 23 moisture calculations may predict a broad range of observed duff consumption and overstory tree 24 mortality levels, limiting its applicability for some management objectives. DMM 600 outputs 25 were only weakly correlated with Keetch-Byram Drought Index (R = 0.30). In addition, we 26
{"title":"Utility of an Instantaneous Moisture Meter for Duff Moisture Prediction in Long-Unburned Longleaf Pine Forests","authors":"E. Engber, J. Varner, Christopher J. Dugaw, Lenya Quinn-Davidson, J. Hiers","doi":"10.5849/SJAF.11-034","DOIUrl":"https://doi.org/10.5849/SJAF.11-034","url":null,"abstract":"14 Duff fires have been implicated in overstory mortality and soil heating in long-unburned pine 15 forests. In the South’s punctuated climate, duff moisture can change rapidly, falling below 16 moisture thresholds that protect trees or increasing following brief downpours. To date, 17 managers lack an instantaneous measure of duff moisture, a hurdle to the implementation of 18 prescribed burns. Here we evaluate a low-cost tool, the Campbell Scientific Duff Moisture Meter 19 (DMM) 600, to estimate duff moisture content in the field. Comparisons of the DMM 600 20 outputs with paired oven-dried duff fuel samples revealed statistically significant differences, 21 with DMM 600 moisture output explaining 54 percent of the variation in oven-dried moisture 22 content. Comparisons with previously published data demonstrate that large variations in duff 23 moisture calculations may predict a broad range of observed duff consumption and overstory tree 24 mortality levels, limiting its applicability for some management objectives. DMM 600 outputs 25 were only weakly correlated with Keetch-Byram Drought Index (R = 0.30). In addition, we 26","PeriodicalId":51154,"journal":{"name":"Southern Journal of Applied Forestry","volume":"37 1","pages":"13-17"},"PeriodicalIF":0.0,"publicationDate":"2013-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.5849/SJAF.11-034","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70978675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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