Precision vegetable seeders were found to have unexpected variation in seed spacing uniformity. A belt seeder and vacuum seeder were evaluated using cabbage (Brassica oleracea L. capitata group) seeded at different seed spacings to determine if seeder uniformity improved with increasing seed spacing. Seeding uniformity of the belt seeder was not affected by seed spacing, but uniformity of the vacuum seeder was. Variation in seed spacing with the vacuum seeder was consistent in absolute units, thus seed spacing nonuniformity (expressed as a percentage of theoretical spacing) decreased with increasing seed spacing. Operating the vacuum seeder with the air pressure seed release mechanism disengaged improved seeder precision. Uniformity and precision of the belt seeder were better than that of the vacuum seeder.
Regina P. Bracy, Richard L. Parish, and Joe E. McCoy
Regina P. Bracy and Richard L. Parish
Stanhay, Carraro, and Gaspardo precision vegetable seeders were evaluated for seeding uniformity with seeds of five vegetable crops—cabbage (Brassica oleracea L. Capitata group), carrot (Daucus carota L.), cucumber (Cucumis sativus L.), onion (Allium cepa L. Cepa group), and spinach (Spinacia oleracea L.). Five measurements [mean, percentage of misses, percentage of multiples, quality of feed, and precision (defined as the coefficient of variation after misses and multiples were discarded)] were used to evaluate seeder uniformity. Using all five measurements provided a more complete determination of the metering uniformity of the seeders than was possible in prior work when only mean and coefficient of variation were used. The belt seeder (Stanhay) was effective at singulating spherical seeds (cabbage) and nearly spherical seeds (onion)as the most precise vacuum seeder (Carraro). Seeding uniformity of all seeders with elongated (carrot and cucumber) or angular (spinach) seeds was inadequate for precision seeding.
Regina P. Bracy and Richard L. Parish
Manufacturers of certain vegetable seeders have promoted their products as precision seeders and implied that their products are more accurate at seeding uniformity than typical agronomic seeders. A comparison of the seeding uniformity of several vegetable seeders and agronomic seeders was made to evaluate this assumption. Two vegetable seeders and two agronomic seeders were evaluated for seeding uniformity and precision using soybean seed. The Stanhay S870 (belt-type) vegetable seeder had the best seeding uniformity and precision spacing of all the seeders tested. The Gaspardo SV255 (vacuum) vegetable seeder and the John Deere 7200 MaxEmerge (fingermeter) agronomic seeder were comparable in seeding uniformity and precision, although fewer skips were noted with the John Deere. The Great Plains 8030 (brushmeter) agronomic seeder had a large number of skips and multiples and poor seeding precision.
R.L. Parish and R.P. Bracy
Prior studies have demonstrated that a Gaspardo vacuum seeder provides less uniform seed spacing than a Stanhay belt seeder. It was hypothesized that the difference was primarily because of the greater seed drop height on the Gaspardo seeder. A Gaspardo metering unit was modified by adding a slide or an enclosed tube to guide the seeds from the release point (seed plate) to 1.0 inch (25 mm) above the bottom of the seed furrow. Seed uniformity tests were conducted with cabbage (Brassica oleracea), onion (Allium cepa), and mustard (Brassica juncea) seeds. The modified planter unit was compared with an unmodified unit. No improvement in seeding uniformity was noted with either the slide or the tube. In fact, seed placement uniformity was degraded with the addition of the slide and tube. Although it is probable that the seed spacing nonuniformity was caused by drop height, attempts to control the seed trajectory were unsuccessful.
Richard L. Parish and Regina P. Bracy
An Earthway garden seeder (model 1001B) is frequently used for seeding small research and demonstration plots as well as home gardens. Seeding uniformity tests were conducted with 18 species of vegetable in this seeder using the planter plates recommended by Earthway, alternate plates, and plates modified by taping off metering ports to change the seeding rates and spacings. Performance with the Earthway seeder with most vegetable seeds would not qualify it as a precision seeder, but the Earthway seeder can do an acceptable job of planting many vegetable seeds in small plots at less than 1/10th the cost of a commercialquality precision seeder. A table giving specific recommendations for each of the 18 species has been prepared to aid research and extension personnel as well as home gardeners.
Davut Karayel and Aziz Özmerzi
The purpose of this research was to examine the effects of different forward speeds of hill dropping melon (Cucumis melo) and watermelon (Citrullus lanatus) seeds with reference to hill dropping uniformity. For this purpose, melon and watermelon seeds were hill dropped with three different seed plates at the forward speeds of 0.5, 1.0, 1.5, and 2.0 m·s–1 (1.64, 3.28, 4.92, and 6.56 ft/s). A precision vacuum seeder unit was used in laboratory tests involving a grease belt test stand. Mean hill distance was not affected by forward speed and seed plates, but mean seed number in hill was affected. In terms of the coefficients of variation of hill distance and seed number in hill, the most suitable forward speed was 0.5 m·s–1. The scattering distance ratios of forward speed of 0.5 and 1.0 m·s–1 were about 20% to 30%, indicating an acceptable level for hill dropping of melon and watermelon.
Richard L. Parish and Regina P. Bracy
Selecting the proper seeder setup to meter a given seed lot effectively can be very difficult for a vegetable grower, especially if the seed lot is not graded for size uniformity. A belt-type seeder should effectively singulate the seeds if the seeds are spherical and uniform because the holes are specifically sized. Seeds that are not graded for size uniformity may not be singulated effectively by a belt-type seeder. A vacuum-type seeder should uniformly meter a wider range of seed sizes better than a belt-type seeder since the holes in the seed plate must only be smaller than the smallest seeds in the lot. Seed lots (graded and ungraded) of two turnip (Brassica rapa L. rapifera group) cultivars were metered with a belt seeder using belts with holes 6/64 inch (2.4 mm) or 7/64 inch (2.8 mm) in diameter or with a vacuum seeder. Neither the belt nor vacuum seeder satisfactorily singulated any of the seed lots. With the larger (7/64 inch) belt holes, there were excessive incidences of multiple seeds per drop. With the smaller (6/64 inch) belt holes, multiple drops and missed seed were excessive. The vacuum seeder also resulted in excessive misses and multiples.
) evaluated belt and vacuum seeders using cabbage seeded at different seed spacings to determine if seeder uniformity was affected by seed spacing. Seeding uniformity of the belt seeder was not affected by seed spacing, but seeding uniformity of the vacuum
dioxide at less than 1.0%. EFFECTIVE USE OF AN INEXPENSIVE GARDEN SEEDER IN RESEARCH PLOTS AND GARDENS An inexpensive garden seeder can deliver adequate seeding uniformity for use in research and demonstration plots as well as gardens. Parish and Bracy (p
Rolston St. Hilaire, Theodore W. Sammis, and John G. Mexal
students with clear guidance on how to sow seeds uniformly and how to determine the planting depth of lettuce seeds based on time of sowing. Yet, 25% of the students did not sow seeds uniformly ( Fig. 2D ) or translate the instructions given in the lecture