scholarly journals Compensating for missing plot observations in forest inventory estimation

2003 ◽  
Vol 33 (10) ◽  
pp. 1990-1997 ◽  
Author(s):  
Ronald E McRoberts

The Enhanced Forest Inventory and Analysis program of the U.S. Forest Service has established a nationwide array of permanent field plots, each representing approximately 2400 ha. Each plot has been assigned to one of five interpenetrating, nonoverlapping panels, with one panel selected for measurement on a rotating basis each year. As with most large surveys, observations for some plots are not obtained. Several techniques for dealing with missing observations were compared with respect to the bias and precision of stratified estimates of mean volume per unit area using data from the State of Indiana in the north-central region of the United States for illustrative purposes. For the proportion of missing plots ranging from 1% to 10%, acceptable results were obtained for techniques that both ignored and replaced missing plot observations, but only when the techniques accounted for differences between plots in private and public ownerships.

2004 ◽  
Vol 18 (1) ◽  
pp. 23-46 ◽  
Author(s):  
Ronald E. McRoberts ◽  
William H. McWilliams ◽  
Gregory A. Reams ◽  
Thomas L. Schmidt ◽  
Jennifer C. Jenkins ◽  
...  

1992 ◽  
Vol 9 (3) ◽  
pp. 82-89 ◽  
Author(s):  
Mark H. Hansen ◽  
Jerold T. Hahn

Abstract This paper describes the procedures used by North Central Forest Experiment Station's Forest Inventory and Analysis Work Unit (NCFIA) in determining stocking, forest type, and stand-size class. The stocking procedure assigns a portion of the stocking to individual trees measured on NCFIA 10-point field plots. Stand size and forest type are determined as functions of the stocking, size, and species of these trees and the physiographic classification of the site. One stand-size classification algorithm used in all states inventoried by NCFIA is described. Three separate forest type classification algorithms used in the Lake States (MI, MN, and WI), Plains States (KS, NE, ND, and SD) and Central States (IA, IL, IN, and MO) are presented. North. J. Appl. For. 9(3):82-89.


2009 ◽  
Vol 10 (1) ◽  
pp. 8 ◽  
Author(s):  
Alison E. Robertson ◽  
Silvia R. Cianzio ◽  
Sarah M. Cerra ◽  
Richard O. Pope

Phytophthora root and stem rot (PRR), caused by the oomycete Phytophthora sojae, is an economically important soybean disease in the north central region of the United States, including Iowa. Previous surveys of the pathogenic diversity of P. sojae in Iowa did not investigate whether multiple pathotypes of the pathogen existed in individual fields. Considering the many pathotypes of P. sojae that have been reported in Iowa, we hypothesized multiple pathotypes could exist within single fields. In the research reported herein, several soil samples were collected systematically from each of two commercial fields with a history of PRR in Iowa, and each soil sample was baited separately for isolates of P. sojae. Numerous pathotypes of P. sojae were detected from both fields. As many as four pathotypes were detected in some soil samples (each consisting of six to eight soil cores), which suggests that a single soybean plant could be subjected to infection by more than one pathotype. This possibility presents important implications in breeding resistant cultivars and in the management of PRR. Accepted for publication 14 July 2009. Published 8 September 2009.


Author(s):  
Robin L. Ewing

Document delivery is a service offered by academic libraries that allows distance education students to access or obtain the research materials required for their studies. These services find the document and send a copy of it to the student (Calvert, 2001). Document delivery services aim to provide the same level of service to on-campus students and to off-campus students. They provide access to library materials at the student’s home institution as well as from other libraries. Document delivery services for distance students are generally part of a library’s Interlibrary Loan Department but document delivery can be a separate department. Some libraries have a division or department dedicated to serving distance students and document delivery is handled there when they exist. In the United States, regional accreditation agencies consider document delivery services to be a vital part of a distance education program. For example, the North Central Association of Colleges and Schools’ Guidelines for Distance Education emphasize that students should have access to the appropriate library resources for the field of study (2000).


2019 ◽  
Vol 118 (3) ◽  
pp. 289-306 ◽  
Author(s):  
Zachary Wurtzebach ◽  
R Justin DeRose ◽  
Renate R Bush ◽  
Sara A Goeking ◽  
Sean Healey ◽  
...  

Abstract In 2012, the US Forest Service promulgated new regulations for land-management planning that emphasize the importance of scientifically credible assessment and monitoring strategies for adaptive forest planning and the maintenance or restoration of ecological integrity. However, in an era of declining budgets, the implementation of robust assessment and monitoring strategies represents a significant challenge for fulfilling the intent of the new planning rule. In this article, we explore opportunities for using data and products produced by the USDA Forest Service’s Forest Inventory and Analysis (FIA) Program to support the implementation of the 2012 Planning Rule. FIA maintains a nationally consistent statistical sample of field plots that covers most national forests with hundreds of plots. We suggest that leveraging FIA data and products can generate efficiencies for assessment, planning, and monitoring requirements detailed in the 2012 Planning Rule, and help fulfill the adaptive intent of the new planning rule. However, strong national leadership and investment in regional-level analytical capacity, FIA liaisons, and decision-support tools are essential for systematically realizing the benefits of FIA data for forest planning across the National Forest System.


2017 ◽  
Vol 27 (5) ◽  
pp. 718-730 ◽  
Author(s):  
David C. Zlesak ◽  
Randy Nelson ◽  
Derald Harp ◽  
Barbara Villarreal ◽  
Nick Howell ◽  
...  

Landscape roses (Rosa sp.) are popular flowering shrubs. Consumers are less willing or able to maintain landscape beds than in years past and require plants that are not only attractive, but well-adapted to regional climatic conditions, soil types, and disease and pest pressures. Marketing and distribution of rose cultivars occurs on a national level; therefore, it is difficult for U.S. consumers in the U.S. Department of Agriculture (USDA) Plant Hardiness Zones 3 to 5 to identify well-adapted, cold-hardy cultivars. Identifying suitable cultivars that have strong genetic resistance to pests and disease and that will tolerate temperature extremes without winter protection in the USDA Plant Hardiness Zones 3 to 5 is of tremendous value to consumers and retailers in northern states. Twenty landscape rose cultivars, primarily developed in north-central North America, were evaluated at five locations in the United States (three in the north-central United States, one in the central United States, and one in the south-central United States) using the low-input, multiyear Earth-Kind® methodology. Six roses had ≥75% plant survival at the end of the study and were in the top 50% of performers for overall mean horticultural rating at each of the three north-central U.S. sites: ‘Lena’, ‘Frontenac’, ‘Ole’, ‘Polar Joy’, ‘Sunrise Sunset’, and ‘Sven’. Five of these six roses met the same criteria at the central United States (exception ‘Lena’) and the south-central United States (exception ‘Polar Joy’) sites. Cultivar, rating time, and their interaction were highly significant, and block effects were not significant for horticultural rating for all single-site analyses of variance. Significant positive correlations were found between sites for flower number, flower diameter, and overall horticultural rating. Significant negative correlations were found between flower number and diameter within each site and also between black spot (Diplocarpon rosae) lesion size from a previous study and overall horticultural rating for three of the five sites. Cane survival ratings were not significantly correlated with overall horticultural rating, suggesting some cultivars can experience severe winter cane dieback, yet recover and perform well. Data from this study benefit multiple stakeholders, including nurseries, landscapers, and consumers, with evidence-based regional cultivar recommendations and breeders desiring to identify regionally adapted parents.


Plant Disease ◽  
2018 ◽  
Vol 102 (9) ◽  
pp. 1779-1784 ◽  
Author(s):  
X. Zhang ◽  
M. Babadoost

This study was conducted to determine characteristics of Xanthomonas cucurbitae, the causal agent of bacterial spot of pumpkin, and survival of the bacterium in pumpkin seeds. Fourteen X. cucurbitae isolates from the north central region of the United States, along with the X. cucurbitae strain 23378 from the American Type Culture Collection, were included in this study. The range of minimum, optimum, and maximum temperatures for colony development of X. cucurbitae were 4 to 6°C, 24 to 30°C, and 34 to 36°C, respectively. Optimum pH for colony development ranged from 6.5 to 8.0. Leaves of 3-week-old pumpkins ‘Howden’ and ‘Dickinson’ were inoculated with X. cucurbitae isolates (108 CFU/ml). There was a significant difference in the postinoculation periods for appearance of bacterial lesions on the leaves among the isolates; however, there was no significant difference in diameters of the lesions on each of the pumpkin cultivar 7 days after inoculation. Four of the isolates caused significantly larger lesions on ‘Dickinson’ leaves than ‘Howden’ leaves. Naturally infected ‘Howden’ pumpkin and inoculated ‘Dickinson’ pumpkin seeds with X. cucurbitae were stored at 4 and 22°C. X. cucurbitae was isolated from both naturally infected and inoculated seeds 24 months after storage at both 4 and 22°C, and the isolated bacteria were pathogenic.


2019 ◽  
Vol 112 (4) ◽  
pp. 1722-1731 ◽  
Author(s):  
Daniela T Pezzini ◽  
Christina D DiFonzo ◽  
Deborah L Finke ◽  
Thomas E Hunt ◽  
Janet J Knodel ◽  
...  

Abstract Stink bugs (Hemiptera: Pentatomidae) are an increasing threat to soybean (Fabales: Fabaceae) production in the North Central Region of the United States, which accounts for 80% of the country’s total soybean production. Characterization of the stink bug community is essential for development of management programs for these pests. However, the composition of the stink bug community in the region is not well defined. This study aimed to address this gap with a 2-yr, 9-state survey. Specifically, we characterized the relative abundance, richness, and diversity of taxa in this community, and assessed phenological differences in abundance of herbivorous and predatory stink bugs. Overall, the stink bug community was dominated by Euschistus spp. (Hemiptera: Pentatomidae) and Chinavia hilaris (Say) (Hemiptera: Pentatomidae). Euschistus variolarius (Palisot de Beauvois) (Hemiptera: Pentatomidae), C. hilaris and Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) were more abundant in the northwestern, southeastern and eastern parts, respectively, of the North Central Region of the United States. Economically significant infestations of herbivorous species occurred in fields in southern parts of the region. Species richness differed across states, while diversity was the same across the region. Herbivorous and predatory species were more abundant during later soybean growth stages. Our results represent the first regional characterization of the stink bug community in soybean fields and will be fundamental for the development of state- and region-specific management programs for these pests in the North Central Region of the United States.


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