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- Author or Editor: David R. Hershey x
Scientific terms should have a single definition to avoid confusion. The noun “herb” has two broad categories of definitions, the first as a plant used in perfumery, as a dye, in cooking as flavoring, etc. and the second as a description of plant habit. Examination of over 30 definitions for the latter meaning of herb revealed great differences. Herb is variously defined as a “nonwoody plant” or as a plant with “annual aboveground stems”, allowing woody plants with annual stems to be called herbs, e.g. Buddleia or Vitex in colder climates. Other definitions restrict herbs to certain portions of the plant kingdom, such as “seed plants” or “vascular plants”. The adjective “herbaceous” is also defined in numerous ways, e.g. “not woody”, “dying to the ground each year”, “having the texture, color, etc. of an ordinary foliage leaf”. The same plant may be termed herb or herbaceous using some definitions, but not others. Since herb and herbaceous have been defined in so many different ways, the terms should be avoided, unless the definition being used is given, and more specific terms used, e.g. nonwoody plant.
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.
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.
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).
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.
Ten women horticulturists who made important contributions to their science are briefly profiled, since virtually no horticulture textbooks mention notable women horticulturists.
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).
Abstract
Probe pH meters are marketed by many horticultural suppliers and cost from $5 to $21. A probe pH meter consists of an analog meter attached to one or two metal probes. To measure pH a probe is pushed into moist growing medium, and the indicator needle points to the pH. Despite low cost and seemingly simple operation, probe pH meters have been criticized as being unsuitable for horticultural use (1, 3). I, therefore, evaluated the accuracy of a probe pH meter for measuring growing media pH.
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).