Thesis (M.S.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on October 23, 2007) Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin-Madison, 1968. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 70-73).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1973. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

The black walnut, Juglans nigra L., is native to the United States (USA) and is a valuable timber and nut tree. Just before the beginning of the 21st century, several western states observed a decline in the health and, later, death of black walnut trees. The pathogen-vector complex now known as thousand cankers disease (TCD) was shown to be the cause. The disease, caused by Geosmithia morbida Kolařik, is vectored by the walnut twig beetle (WTB), Pityophthorus juglandis Blackman. Thousands of WTB will swarm and enter a tree vectoring the fungus at each entry point where cankers then develop, quickly expand, coalesce and kill the branch or stem. The disease has been confirmed across the USA and in parts of Europe. The research and development of resistant cultivars is important to maintain native populations and livelihoods. The purpose of this project was to evaluate black walnut and hybrid trees for resistance to TCD through direct inoculation with the pathogen G. morbida. Inoculation of limbs took place in early summer of 2015, 2016 and 2017 at the Cyril Reed Funk Research Farm in Richmond, UT and Dayton, ID. Inoculated limbs were removed from the tree after senescence and canker size measured. An average of 336 trees were inoculated. One tree consistently exhibited resistance to TCD indicated by no canker staining. An additional 14 trees exhibited resistance for two of the three years. The results of this project indicate that breeding for resistance to TCD could be a management option for the disease.

Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 25, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Robert L. Kallenbach. Vita. Includes bibliographical references.

Thesis--Virginia Polytechnic Institute and State University. / Also available via the Internet.

Silvopastoral management has potential to diversify and increase the output from livestock production systems. Silvopasture production offers solutions to many management issues associated with grazing systems in the Appalachian region. Several tree species have been proposed for silvopastures in humid temperate regions, but little data comparing animal performance from systems with different deciduous tree species are available. Forage and animal performance was compared from open systems (i.e., no trees) with that from silvopastures containing 13-yr-old honeylocust (Gleditsia triacanthos) or black walnut (Juglans nigra) trees. Cool-season grass-legume pastures were rotationally stocked with hair sheep crosses from mid-June through September. The objective of this project was to determine carcass characteristics and meat quality of hair sheep crosses grazing honey locust or black walnut silvopastures in comparison with traditional pasture systems. Forage production varied by year with black walnut having lower production, especially in the 2009 season with black walnut producing less forage compared to open pastures and honeylocust silvopastures (P=0.0008). Only small differences in forage nutritive value were observed. Total gains and average daily gains (ADG) did not differ by treatment in 2008, but during the 2009 season black walnut silvopastures produced half the total gains (P=0.0427) and ADG (P=0.0513) of open pastures and honeylocust silvopastures. Carcass characteristics evaluated did not vary among treatments except hot carcass weight with black walnut having lower weights (P=.0045). Meat quality characteristics did not vary among treatments (P>0.1). Shear force and fat content showed great differences and varied by year (P<0.05). Overall, carcass and meat quality was similar for all treatments showing great promise for silvopastures. / Master of Science

Incorporating high-sugar varieties of honeylocust (Gleditsia triacanthos L.) or black walnut trees (Jugulans nigra L.) into pasture systems may improve soil and water quality, increase biodiversity, and diversify farm incomes. Studies of productivity and management are needed to understand the trees' potential. Research was conducted in the agroforestry demonstration plots at Virginia Tech's Kentland Farms to 1) estimate both the variability of seedpod yield and nutritive value from juvenile Millwood honeylocust trees, 2) measure changes in nutritive value and digestibility over-winter in Millwood and wild-type honeylocust seedpods, and 3) estimate black walnut biomass productivity, timber quality, nut production, and kernel quality in response to tree density and topography within an emulated silvopasture. Ground Millwood seedpods were comparable to whole-ear dent corn in terms of nutritive value. Both ground pods and seeds were highly digestible (78.7 and 96.3%, respectively) and low in fiber and lignin. Seeds, with over 20% crude protein (CP), have potential as a CP supplement. Millwood trees displayed alternate bearing patterns with 3-yr average yields of approximately 12 kg tree-1. Total aboveground biomass for black walnut trees planted on toe-slopes (109.0 kg) was 72% greater than at back slopes (63.2 kg) and nearly 3-fold more than at shoulder-slopes (37.6 kg). Nut yields ranged from 0 to 7.9 kg of dried, hulled nuts tree-1 year-1. All walnut trees displayed alternate nut bearing patterns and nut production was marked by high variability. / Master of Science

Call number: LD2668 .T4 1978 B37 / Master of Science

Master of Science / Food Science - Human Nutrition / Delores Chambers / Researchers evaluated the flavor characteristics of seven black walnut (Juglans nigra L.) cultivars: Brown Nugget, Davidson, Emma K, Football, Sparks 127, Sparrow, and Tomboy using descriptive sensory analysis. Seven trained panelists developed a lexicon for the black walnuts and scored the intensities of the samples for 22 flavor and taste attributes. Results showed that the 7 samples differed significantly (P ≤ 0.05) on 13 of the attributes. For the majority of the attributes, only Emma K differed from the rest of the cultivars by being characterized with lower scores for black walnut ID, overall nutty, nutty-grain-like, nutty-buttery, floral/fruity, oily, and overall sweet. It also was higher in acrid, burnt, fruity-dark, musty/earthy, rancid, and bitter attributes. Researchers then incorporated the black walnut cultivars into a simple cookie recipe and evaluated the samples for differences in flavor attributes using the same trained panelists. Nine of the 25 attributes differed significantly across cultivars: black walnut ID, overall nutty, nutty-buttery, brown, toasted, acrid, rancid, overall sweet, and sweet (P ≤ 0.05). Lower mean scores in black walnut ID, overall nutty, and sweet and higher mean scores in rancid and acrid characterized the Emma K cookie. A PCA biplot revealed that cookies with Football, Sparks 127, and Sparrow walnuts related with one another and the attributes nutty-woody, leavening, and piney. A consumer acceptance test for six of the cookies (Tomboy cultivar was excluded) was also performed. There were four significant clusters of consumers that differed in their acceptance of the cookie samples. Cluster 1 preferred Football, clusters 2 and 3 each showed no overall preference, and cluster 4 preferred Emma K suggesting a set of niche consumers for black walnut cookies. Results presented in this paper can assist black walnut growers in determining which cultivars to plant and harvest. By knowing which cultivars have the most desirable flavor characteristics, growers can focus time and resources on select cultivars, therefore resulting in higher quality black walnuts as products to be sold to consumers in various formats. By consciously choosing which cultivars to harvest, black walnut growers can meet market demand and increase profit.