associated with compaction can reduce turfgrass quality, percentage of cover, total nonstructural carbon, shoot density, verdure, and root growth ( Carrow, 1980 ). Sand has a relatively large volume of macropore space and is inherently low in silt and clay
Alexander R. Kowalewski, John N. Rogers III, James R. Crum, and Jeffrey C. Dunne
Lewis W. Jett, Ronald D. Morse, and Charles R. O'Dell
There is a strong consumer demand for single-head broccoli (Brassica oleracea L. var. italica) that yields more florets per unit weight than bunching broccoli. Two spatial arrangements (single vs. twin row) and five plant densities (10.8, 7.2, 5.4, 4.3, and 3.6 plants/m2) were examined for single-head broccoli production. Spatial arrangement had no significant effect on any measured attribute, although the twin-row arrangement resulted in less plant damage with each harvest. For exclusive production of quality, single-head broccoli with high yields of marketable florets, 3.6 plants/m2 (46-cm within-row spacing) should be used.
Sylvie Jenni and Gaetan Bourgeois
initiation, crisphead lettuce leaves continue to grow, overlapping onto each other to form a head of increasing density and size. At harvest time, maturity is evaluated on the basis of density and size ( Garrett et al., 1969 ; Goddard et al., 1972
Ossama Kodad and Rafel Socias i Company
, a high fruit set is considered for a desirable trait in almond, although the adequate level of fruit set in any cultivar must be related to its flower bud density and to its flower quality ( Bernad and Socias i Company, 1998 ; Socias i Company et al
Susan L. Barkley, Sushila Chaudhari, Jonathan R. Schultheis, Katherine M. Jennings, Stephen G. Bullen, and David W. Monks
important component in the study. A sweetpotato crop is established with nonrooted cuttings (slips), which are vegetatively produced in field propagation beds. North Carolina growers use a wide (24 to 73 bu/1000 ft 2 ) range of seed root densities to produce
Daljeet S. Dhaliwal and Martin M. Williams II
relies heavily on established grain-type soybean management guidelines; however, research to confirm or deny their appropriateness is lacking. One fundamental decision for growing a crop is to determine the target plant population density, hereafter
Stefano Musacchi, Federico Gagliardi, and Sara Serra
; Weber, 2001 ). The dwarfing rootstock series Gisela ® , developed at the Liebig University of Giessen in Germany, induce early bearing of sweet cherry. Gisela ® 5 and Gisela ® 6, in particular, show promise for use in high-density cherry orchards
Watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai] cultivars StarBrite and Crimson Sweet were grown during 1991 and 1992 in rows 1.5 m apart at plant spacings of 0.9, 1.5, or 2.2 m. Total fruit yield, marketable fruit yield, fruit-weight distribution, and estimated gross returns were determined for each spacing treatment. Total and marketable fruit yields were greater overall for `StarBrite' than for `Crimson Sweet'. Except for 1991 `Crimson Sweet' yields, marketable fruit yields per unit land area increased 29% to 34% as plant spacing decreased from 2.2 to 0.9 m. The yield component contributing the most to increased yields with high-density plantings was increased fruit count per unit land area. Average fruit weight responded only slightly to decreased plant spacing. Fruit-weight distribution on a relative frequency scale was stable regardless of plant spacing or production year. The potential for increasing gross returns per unit land area exists by increasing watermelon plant populations beyond the current Georgia recommendation of 2500 to 3000 plants/ha.
Theodore J.K. Radovich and Matthew D. Kleinhenz
Volume measurements are useful in crop quality management because they offer three-dimensional estimates of commodity size, which is often closely related to commodity weight and density. The objective of this study was to compare volume estimates calculated with the sphere and spherical ellipsoid volume formulae with direct measures of volume via water displacement across a population of cabbage (Brassica oleracea Capitata Group) heads varying widely in shape. A total of 157 heads with polar (P): equatorial (E) diameter ratios ranging between 0.5 (flat) to 2.1 (tall) were harvested at horticultural maturity from plants grown in 2002 and 2003 at the Ohio Agricultural Research and Development Center (OARDC) in Wooster, Ohio. The sphere formula underestimated volume in heads with P:E ratios <1 and overestimated volume in heads with P:E ratios >1. Use of the spherical ellipsoid formula reduced the shapedependency of volume estimates and was determined to be a valuable tool for the accurate, precise, and rapid measurement of head volume.
Martin M. Williams II
changed little over the last 80 years in the United States despite 6-fold yield gains ( Egli, 2015 ). The sink limitation has been largely overcome in grain corn by improving plant density tolerance (also known as crowding stress tolerance) and planting