Annual applications of N, P, and K fertilizers were broadcast for 4 years around black walnut trees (Juglans nigra L.) in an upland plantation to determine their effect on nut production and foliar nutrient levels. Fertilization significantly (P = 0.05) increased nut production, treatments containing P with N and/or K being most effective. Doubling the rate of application did not produce a corresponding yield in nuts. Increases in leaf concentrations of N, P, and K were associated with increasing treatment levels of these elements. Levels of all elements tested, except P, were above deficiency levels. The modest gain in production suggests that soil fertility was not a major factor limiting nut production for trees in this study.
specifically nut crops is the major constraint for breeders ( van Nocker and Gardiner, 2014 ). One of the basic strategies for reducing the length of breeding cycle is the introduction of superior genotypes. Moreover, germplasm screening of fruit trees in
were adequately thinned. An objective of this study was to determine the maximum cropload ‘Pawnee’ trees in this study could carry and return a similar crop the next year. In addition, selected nut quality characteristics were correlated with cropload
CURRENT LIMITATIONS ON BLACK WALNUT PRODUCTION In 1955, there were 10 nut cracking plants specializing in black walnut nutmeat production, capable of processing 27.2 million kilograms of dried in-shell nuts, yielding 3.3 million kilograms of edible
, 2009 ). Japanese chestnut differs from Chinese chestnut in morphological characteristics such as nut size, leaf shape, and hair density on young leaves ( Woodroof, 1979 ). Japanese chestnut cultivars are believed to have been developed from wild
Persian walnut ( Juglans regia L.), widely cultivated for nut production, is an ancient species ( Fjellstrom and Parfitt, 1994 ; Vahdati, 2000 ) originating in areas of Central Asia, including Iran. Wild trees of this species are widely dispersed
Botanical Gardens, and Walter Hill, superintendent of Brisbane’s Botanical Gardens. The nut was named in honor of Mueller’s good friend, John Macadam, a prominent scientist, philosopher, and politician. The macadamia tree, a subtropical evergreen of the
did not increase orchard productivity, nut yield, or quality. Wood (2009) suggested that moderate-width (2.4 m from the tree axis), short-cycle (annual or biennial pruning) mechanical hedging did not appear efficacious for southeastern pecan
sources of food and construction materials. Even now, they are commercially grown throughout Japan for food, and chestnut orchards covered more than 21,400 ha in 2011, ranking fourth among woody fruit and nut crops in Japan after citrus, apple, and
Chestnut cultivation for nut production in the midwestern United States has experienced accelerated adoption in recent years, with the number of farms increasing 57% between 2012 and 2017, and more than 300 orchards reaching bearing age ( USDA