Recently, rising energy costs have led to a dramatic increase in the price of synthetic fertilizer ( Huang, 2009 ). Between 2002 and 2007 the cost of synthetic fertilizer N per acre rose by over 200% for pecan ( Wells, 2009a ). This sharp increase
I.E. Yates and Darrell Sparks
We gratefully acknowledge the technical assistance of Lamar Jenkins, Donnie Maxey, and Joyce Lambert and the cooperation of Frank P. Wetherbee and use of his pecan trees at Flint River Pecan Co., Albany, Ga. Trade names are used in this
Humberto Núñez-Moreno, James L. Walworth, Andrew P. Pond, and Michael W. Kilby
Spraying zinc (Zn) solutions onto the tree canopy is the standard method for supplying this nutrient to pecan trees [ Carya illinoinensis (Wangenh.) K. Koch]. Zinc applied to soil reacts with hydroxyls and carbonates in alkaline and calcareous
Bruce W. Wood
Pecan [Carya illinoinensis (Wangenh.) K. Koch] nursery transplants performed best on establishment in nonirrigated orchards when using large trees planted early in the dormant season. After 6 years, growth and survival of bare-root transplants were equal to that of containerized transplants when established during the dormant season. Reducing transplant trunk height by ≤75% at planting did not affect subsequent tree survival, although rate of height growth and tree vigor increased such that there was no difference between pruned and nonpruned trees after 3 years, except that pruned trees appeared to possess greater vigor. There also were no differences in growth or survival between augured and subsoil + augured planting sites within 6 years of transplanting, and there were no differences between root pruned (severe tap or lateral root pruning) and nonpruned trees.
Michael W. Smith, Becky L. Carroll, and Becky S. Cheary
`Dodd' pecan seedlings [Carya illinoinensis (Wangenh.) K. Koch] were chilled at 6C for 0 to 1800 hours in 300-hour intervals and percent budbreak and days to budbreak recorded. Chilling duration required for ≥ 50% budbreak was 900 hours. Chilling > 900 hours increased budbreak percentage and reduced time to budbreak. `Dodd' seedlings chilled at 1, 5, or 9C for 0 to 2500 hours in 500-hour intervals had more lateral budbreak after 1000 hours of chilling at SC than at 1 or 9C. When chilling hours ranged from 1500 to 2500, 1C increased budbreak of the first lateral bud compared with 5 or 9C. As chilling was increased from 1000 to 2500 hours, the days to budbreak declined, and the uniformity of budbreak increased.
Bruce W. Wood
Irregularity of fruit set is a common problem of commercial pecan ( C. illinoinensis ) orchards and can be partially due to poor flower fertilization. Poor fertilization of pistillate flowers can be due to several factors, some of which are
Bruce W. Wood and Deane Stahmann
An ever increasing cost:price squeeze on the profitability of pecan (Carya illinoinensis) farming is driving a search for alternate husbandry approaches. `Wichita' and `Western' trees maintained at relatively high tree population density, by mechanized hedge pruning and topping, produced greater nut yield than an orchard treatment in which tree population density was reduced by tree thinning (144% for `Wichita' and 113% for `Western Schley'). Evaluation of three different hedge pruning strategies, over a 20-year period, identified a discrete canopy hedge pruning and topping strategy using a 2-year cycle, as being superior to that of a discrete canopy hedge pruning and topping strategy using an 8-year cycle, but not as good as a continuous canopy hedge pruning and topping strategy using a 1-year cycle. An evaluation of 21 commercial cultivars indicated that nut yields of essentially all cultivars can be relatively high if properly hedge pruned [annual in-shell nut yields of 2200 to 3626 lb/acre (2465.8 to 4064.1 kg·ha-1), depending on cultivar]. Comparative alternate bearing intensity and nut quality characteristics are reported for 21 cultivars. These evaluations indicate that pecan orchards can be highly productive, with substantially reduced alternate bearing, when managed via a hedge-row-like pruning strategy giving narrow canopies [3403 lb/acre (3814.2 kg·ha-1) for `Wichita' and 3472 lb/acre (3891.5 kg·ha-1) for `Western Schley']. North-south-oriented (N-S) hedgerows produced higher yields that did east-west (E-W) hedgerows (yield for N-S `Wichita' was 158% that of E-W trees and N-S `Western Schley' was 174% that of E-W trees).
These data indicate that mechanized hedge pruning and topping offers an attractive alternative to the conventional husbandry paradigm.
Bruce W. Wood
Natural selection operating over evolutionary time has produced pecan as an economically important species that exhibits pronounced biennial-like alternations in seed production as a strategy for ensuring long-term reproductive success. This year
Marisa Y. Thompson, Jennifer Randall, Richard J. Heerema, and Dawn VanLeeuwen
Alternate bearing (AB) poses a major challenge for the pecan [ Carya illinoinensis (Wangenh.) K. Koch.] industry ( Wood, 2003 ). AB refers to a tendency for wide season-to-season fluctuations in cropping intensity. This is often expressed as a
W.A. (Bill) Gustafson Jr. and Todd M. Morrissey
The Northern Pecan Research Program was established in 1979 and designed to determine the potential of growing the northern pecan as both an ornamental shade tree and as a possible crop in Nebraska. In 1983, 2 year old seedlings planted in 1981 were grafted to 54 superior pecan clones/cultivars (total of 324 trees) in a two-acre orchard in Lincoln, NE. Most of these clones were selected from native trees growing in and along the Mississippi River Valley in Northeast Iowa/Northwest Illinois, and the Missouri River Valley in Northwest Missouri/Northeast Kansas. These pecans were specifically selected for having the potential to survive winter temps to -35° F and produce crops in a 130-180 day growing season. There is now a need to research the production of pecans in a commercial orchard situation. The past 9 years of research has demonstrated that pecans will survive and produce an edible crop with excellent quality and food value.