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On Fortune.com, an article about slavery in Libya prefaced by a Dove commercial: “I don’t want there to be white marks,” a potential buyer says, inspecting a shirt while a lively tune plays in the background. The ad is for an invisible dry spray. I laugh...

Chapter 18 of the Vegetable Production Handbook.

Chapter 13 of the Vegetable Production Handbook.

Chapter 7 of the Vegetable Production Handbook.

Chapter 2 of the Vegetable Production Handbook

Chapter 8 of the Vegetable Production Handbook.

Recent increases in irrigated hectares in the Southeastern US have enabled growers to obtain higher yields through applying nutrients through irrigation water. Therefore, many growers apply nutrients through irrigation systems, known as fertigation. Currently, there are no practical decision-making tools available for variable-rate application of nitrogen (N) through overhead sprinkler irrigation systems. Therefore, field tests were conducted on cotton (Gossypium hirsutum L.) during the 2016 and 2017 growing seasons to 1) adapt the Clemson sensor-based N recommendation algorithms from a single side-dress application to multiple applications through an overhead irrigation system; and 2) to compare sensor-based VRFS with conventional nutrient management methods in terms of N use efficiency (NUE) and crop responses on three soil types. Two seasons of testing Clemson N prediction algorithms to apply multiple applications of N were very promising. The multiple applications of N compared to the grower’s conventional methods (even though less N was applied) had no impact on yields in either growing season. There was no difference in cotton yields between 101 and 135 kg/ha N applications in either management zone. Also, there were no differences in yield between sensor-based, multiple N applications and conventional N management techniques. In relation to comparisons of the sensor methods only applying N in three or four applications, statistically increased yields compared to single or split applications in 2016. Applying N in four applications, statistically increased yields compared to single, split or triple applications in 2017. When the sensor-based methods were compared to the grower’s conventional methods averaged over four treatments, the sensor-based N applications reduced fertilizer requirement by 69% in 2016 and 57% in 2017 compared to grower’s conventional methods. When comparing N rates among the four sensor-based methods (three or four) applications, increased N rates by 22 kg/ha in 2016 and 26 kg/ha in 2017 compared to single or split applications but increased the cotton lint yields by 272 and 139 kg/ha, for 2016 and 2017, respectively.

This chapter covers production of cucurbits, such as cantaloupe, cucumber, squash, watermelon, and pumpkin.

Cotton growers in the southern USA are facing new production problems that are reducing farm profits and sustainability: 1) herbicide-resistant weeds are spreading throughout the Southeast, 2) thrips are consistently ranked as an important insect pest group Beltwide, 3) the most effective tool for managing nematodes and thrips (aldicarb) currently is only available in the southeastern USA in limited amounts, and 4) fuel costs have increased significantly over the last ten years. An interseeding system was developed at Clemson University that allows planting of cotton into standing wheat, about 2 - 3 weeks before wheat harvest. This system, which combines benefits of crop residue and minimum tillage operations, has the potential to alleviate many of the production problems cited above, while enhancing farm profits and soil properties. Crop residue associated with the interseeding production system reduced weed populations and required significantly less herbicide inputs compared with the conventional system. Columbia lance nematodes populations were reduced in the interseeding system by 83% without an application of nematicide. Populations of thrips were reduced by 74% in the interseeding production system. No differences were observed between the yields from interseeded and the conventional full-season cotton. However, revenues from the interseeding system were higher due to harvest of the wheat crop. In addition, the interseeding system consumed 35% less fuel than the conventional production systems.

Cotton root growth is often hindered in the Southeastern U.S. due to the presence of root-restricting soil layers. Tillage must be used to temporarily remove this compacted soil layer to allow root growth to depths needed to sustain plants during periods of drought. However, the use of a uniform depth of tillage may be an inefficient use of energy due to the varying depth of this root-restricting layer. Therefore, the objective of this project was to develop and test equipment for controlling tillage depth “on-the-go” to match the soil physical parameters, and to determine the effects of site-specific tillage on soil physical properties, energy requirements, and plant responses in cotton production. Site-specific tillage operations reduced fuel consumption by 45% compared to conventional constant-depth tillage. Only 20% of the test field required tillage at recommended depth of 38-cm deep for Coastal Plain soils. Cotton taproot length in the variable-depth tillage plots was 96% longer than those in the no-till plots (39 vs. 19.8 cm). Statistically, there was no difference in cotton lint yield between conventional and the variable-depth tillage. Deep tillage (conventional or variable-rate) increased cotton lint yields by 20% compared to no-till.

Nutrients are injected through overhead irrigation systems at a uniform rate in a process known as fertigation. The highly variable soils in the Southeastern US pose challenges for effective fertigation. Currently, there is no variable-rate fertigation system available to apply the correct amount of N within a field through an overhead irrigation system. Therefore, the objective of this study was to develop and test a variable-rate N application system that works independently of irrigation water flow for site-specific N application. The variable-rate fertigation system (VRFS) was designed to apply different rates N using a pulse width modulation technique. The VRFS utilized the Clemson Lateral Irrigation Control software which controlled the solenoids in each zone by turning the N supply on and off (pulsing) for each zone. In this study, four tests were conducted to determine the uniformity of the VRFS. In test # 1, the pump output showed a linear slope relationship and was the same for water and N. In test # 2, nozzle flow and uniformity were determined using four different irrigation system travel speeds at N application rates of 31, 59, 88, and 113 kg/ha. There was a strong correlation (R2 = 0.9998) between irrigation system speed and N rate. In test # 3, the uniformity across the length of the irrigation system was determined. The nozzles produced an average flow of 31.1, 58.7, 87.6, and 112.7 kg N/ha with an overall average error of 0.1% across all N rates. Results also showed the system was capable of accurately applying N based on prescription maps with an error of less than 1.8%. Test # 4 was conducted to determine the accuracy of the map-based controller system for applying variable rate N. There was a strong correlation between target N and actual N rates (R2 = 0.9999). In summary, the VRFS applied the correct amounts of N within each zone by either manually controlling the pulsing mechanism or utilizing a prescription map to apply different rates throughout the field.

Nutrient application systems are designed to apply a relatively uniform amount of a fertilizer to agricultural fields. However, considerable variation in soil texture and other characteristics often occurs within and across production fields, which could have a major impact on fertilizer management strategies. Therefore, uniform application of a fertilizer over the entire field can be both costly and environmentally unsound. Due to their rugged and fool-proof design, crankshaft type piston pumps are widely used in agriculture. The on-the-go outlet flow of these pumps can only be varied by changing the drive shaft speed for each pump stroke setting. But only a limited range of flow rates can be achieved by changing the drive shaft speed. There is a need for an electronic controller, which can adjust the pump stroke on-the-go, for real-time, variable-rate application of crop nutrients. The Clemson “Electro-me-chanical controller for adjusting pump stroke on-the-go” was designed to replace the current manual stroke adjustment system on positive displacement piston pumps. This affordable system can be retrofitted on most John Blue - piston pumps for real-time adjustment of the pump stroke and can be controlled using pre-described position sequences (map-based) or real-time sensor commands (such as optical, pressure, and flow sensors) combined with fertilizer calculation algorithms. In addition, it can adjust pump stroke manually, using an eclectic dial from the tractor’s cab.

Applying insufficient nitrogen (N) in a highly responsive crop, such as corn, results in lower grain yield, quality, and profits. On the other hand, when nitrogen is applied in excess of crop needs, profit is reduced and negative environmental consequences are likely. The objective of this study was to develop and employ a sensor-based algorithm to determine the mid-season N requirements for deficit-irrigated corn in Coastal Plain soils. The algorithm was developed using varied prescription rate N plot on two soil types. The test plots received nine different rates of N fertilizer, replicated 5 times in plots of each soil type using a Randomized Complete Block design. A 6-row GreenSeeker optical sensor was used to measure plant NDVI, between the V6 to V8 growth stages. The sensor readings were used to develop an algorithm to be used in the estimation of side-dress N application in corn. The NDVI sensor readings were collected at the V6 to V8 growth stage during the 2015 and 2016 growing seasons correlated with actual corn yields (R2 > 0.68, p < 0.001). In-Season Estimated yield (INSEY) was used along with the actual yield to produce a yield potential for each growing season for deficit-irrigated corn crop. In summary, the algorithm developed from the NDVI readings reduced N application rates by 21% and 34% in soil types 1 and 2, respectively, compared to the normal grower practice (226 kg N/ha) with no reduction in corn yields.

Soil compaction is a significant problem in the Southeastern USA. This compacted zone or hardpan limits root penetration below this layer and reduces potential yield and makes plants more susceptible to drought induced stresses. Soil compaction in this region is managed using costly annual deep tillage at or before planting and there is a great interest in reducing and/or eliminating annual tillage operations to lower production costs. Deep rooted cool season cover crops can penetrate this compacted soil zone and create channels, which cash crop roots, such as cotton, could follow to capture moisture and nutrients stored in the subsoil. The cool season cover crop roots would reduce the need for annual deep tillage prior to planting, increases soil organic matter, which provides greater water infiltration and available water holding capacity. Field studies were conducted for two years with three different soil series to determine the effects of tillage systems and cool season cover crops on the soil chemical and physical properties, yield responses, and pest pressure. Results showed that cool season cover crops significantly reduced soil compaction, increased cotton lint yield and soil moisture content, reduced nematode population densities, and increased soil available P, K, Mn, and organic matter content compared to the conventional no-cover crop.

Dizzied by sweat-reek and getting-it-on, a pastor leans over the bed for his house shoes with the gossipy soles. Cricket in a tree outside the cracked window like a pacemaker. Peacemaker, for years he’d Jesused his way through rent and cheap groceries, his wife’s sleep a sentence missing its period while he finds his hands fluffing another woman’s thighs to lie on. You do not finish this story, so I do not believe it is true though your words smash onward, are steeds in a pouty romance novel percussing the night into grain and curiosity. You kiss my neck and a horseshoe spirals my throat, a moat gathering momentum in a glut of yeses. I say Jesus meaning more, meaning lock the door, the winds can be nosy. I say the cricket is a maddened wife, her nose pressed to the glass like an altar. We all kneel to pray, the weight of God on our shoulders as we, guilt-shaken, scream as He enters.