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  • Author or Editor: David R. Hershey x
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Abstract

Electrical conductivity (EC) measurement is widely used in horticulture to estimate salinity and fertilizer levels in irrigation waters, nutrient solutions, soils, and growing media (1–4). EC often is referred to as specific conductance (5), conductivity (1), or soluble salts; however, the term EC has been used widely in scientific literature (2–4).

Open Access

Abstract

The pH of a plant growing medium is a major determinant of nutrient availability and plant growth (1), so monitoring the pH of growing media is an important management practice. The pH of growing media can be measured colorimetrically with test papers or indicator solutions (2, 4) or potentiometrically with a glass electrode pH meter (1, 2, 6). Colorblind people, estimated to be 10% of the male population, cannot use colorimetric methods (3).

Open Access

Abstract

ASHS specifies that minimum heights for poster lettering be 25 mm for the titles, authors, and institutions and 12.5 mm for everything else (ASHS, 1988). A survey of 167 posters in Poster Session 1 at the 1988 Annual Meeting indicated that these required minimum lettering sizes are usually not met (Table 1). One reason why these minimums are rarely met is that the minimum heights are unrealistic. The minimum heights were established for 2.4 × 1.2-m posters and not reduced when poster area was halved to 1.2 by 1.2 m. The 1:1 ratio between title and author/institution letter heights is not proportional because title lettering is nearly always taller than author/institution lettering. For example, HortScience titles are 5 mm tall with author/institution lettering 2.5 mm high. Thus, the smaller lettering for authors/institutions compared to titles on ASHS posters is understandable.

Open Access

Abstract

Byrne (1988) discussed the confusion between the words “pollenizer” and “pollinator”. A mnemonic device to remember the difference between the terms is to associate the “t” in pollinator with the word “transfer”, since the definition of pollinator is “the agent of pollen transfer” (Byrne, 1988).

Open Access

Abstract

Shoot or leaf cuttings can be rooted in flats of perlite under intermittent mist for use in a static solution culture system (Hershey and Merritt, 1986). However, removing perlite from the roots before transfer to hydroponics is tedious and damages the roots; also, all the perlite cannot be removed, which causes errors in dry mass and nutrient concentration determinations. A hydroponic propagation system was constructed of inexpensive, readily available materials that allowed rooting of large numbers of cuttings under intermittent mist.

Open Access

Abstract

It is hoped that Science Editor Lipton’s opinion [ASHS Newsletter 5(2):1–2] that horticultural research publications are free of fraud is correct, as fraud is typically very difficult to prove and there are considerable pressures to “publish or perish”, even in horticulture. Unfortunately, a type of fraud seems widespread in commercial horticulture in the form of “miraculous” claims for horticultural products, such as fertilizers and biocatalysts. This type of fraud reflects badly on horticultural science; therefore, horticultural scientists have a duty to conduct research that tests such claims.

Open Access

Abstract

The saturated medium extract (SME) method of container media testing for pH, electrical conductivity (EC), and nutrient levels is generally considered the best procedure for research and routine analysis (1, 5-8). However, various soil : water ratio methods (e.g., 1:1.5, 1:2, 1:5) are widely used (1, 2), partly because they do not require a vacuum extraction, as does the SME method. The use of so many different methods creates considerable confusion (5). Vacuum extraction of saturated media is traditionally performed with a porcelain Buchner funnel ($26 for 9-cm size) and a side-arm, glass vacuum flask ($13 for 500ml size) (2, 6). Less-expensive, unbreakable polypropylene Buchner funnels and vacuum flasks are available. However, they have several disadvantages: they easily tip over when the Buchner funnel contains saturated media, are difficult to dry quickly if several samples need to be run in succession with only one vacuum flask, and only are available through scientific instead of horticultural suppliers.

Open Access

Abstract

As horticultural scientists, we are greatly concerned with numbers—the number of refereed articles we can publish, the number of research grant dollars we can obtain, the number of people served by our extension programs, and the number of students enrolled in our horticultural curricula. One number that we do not usually consider is the distribution number for the horticultural periodicals in which we publish.

Open Access