Crop Sprayer Research Articles

Performance of Different Spray Nozzles in the Application of Defoliant on Cotton Plants (Gossypium hirsutum L.)

Defoliant spraying is an important link in the mechanized cotton harvest because adequate and uniform spraying can improve defoliation quality and reduce cotton trash content. In defoliant application, application volume and spraying technology are extremely important. In this study, the effectiveness of defoliant application to cotton plant that has come to harvest with two different application volumes and three different types of nozzles with a standard field crop sprayer was determined. Application rates were 250 and 400 L/ha and spraying nozzles were: (1) standard flat fan nozzle (TP8006), (2) air induction nozzle (AI 11002-VS) and (3) dual pattern nozzle (AI307003VP). A tracer (BSF) and defoliant were applied to mature cotton with approximately 60% open bolls and samplings for BSF deposition and spray coverage on cotton plant were done at two plant height (upper layer, lower layer) of plant. Before and after spraying, bolls open and leaves rate on cotton plants were calculated and filter papers were used to detect BSF deposition and water sensitive papers (WSP) were used to measure coverage rate of spraying methods used. Spectrofluorophotometer was used to detect the amount of tracer deposition on targets and an image process computer program was used to measure coverage rate on WSP. In analysis conclusions showed that air induction nozzle (AI 11002-VS), achieved better results than the dual pattern and standard flat fan nozzles in terms of higher depositions, coverages and leaf defoliations and boll opening rates. AI nozzles operating at 250 L/ha application rate provide the highest deposition and coverage rate on applications of defoliant, in addition, BSF as an indicator of the defoliant used reached on leaf beneath in merely this spray nozzle. After defoliation boll opining rate was 85-% on the 7th and 12th days after spraying and falling rate of leaves was 76-% at application rate of 250 L/ha with air induction (AI1102) nozzle.

A new system for measuring boom displacement in a field crop sprayer

This study proposes an innovative system for measuring the displacement of a sprayer boom’s tips and calculating their velocity and acceleration in the horizontal and the vertical plane. The system measures the length of measuring cables which are attached at the end of a sprayer boom’s tips. Two supports are mounted in the central part of the sprayer boom. Absolute rotary encoders with measuring reels and tension springs are attached to the supports, which enables the system to determine changes in the position of boom arms in two perpendicular directions. The signals generated by each encoder are transmitted to a computer by a rapid data acquisition device, and they are transposed to the indicated parameters. The designed system can be used to measure sprayer boom displacement both in the field and in laboratory experimental tracks.

Influence of the instability of the field crop sprayer boom on the spraying uniformity

The purpose of the paper was to determine the influence of the instability of the sprayer field boom on the amount of working fluid applied to the sprayed plants. To achieve such aim, experiment was planned with the use of an obstacle course specially designed for this purpose and using artificial plants. Three nozzles of different types were investigated, i.e., universal flat-jet ISO F-03-110 (F110), low-drift ISO LD-03-110 (LD) and injector (anti-drift) ISO-03-110 MiniDrift (MD). Obtained results indicate that obstacles have clearly noticeable influence of spraying quality, understood as level and stability of working fluid deposition values. The worst results were obtained for MD nozzle while the best results were obtained for LD nozzle, both in terms of under/overdosing the working fluid (maximum 36% of overdose) and stability of results, what can lead to the conclusion that LD nozzles should be recommended for spraying fields with rough surfaces. • Influence of the sprayer boom instability on the spraying quality was evaluated. • Obstacle course was prepared according to the guidelines of the ISO 22763 standard. • Evaluated were three types of nozzles. • Variability of working fluid deposition was the biggest for anti-drift nozzle. • Low-drift nozzle seems to be the most appropriate for spraying uneven fields.

Development and Evaluation of a Prototype Self-Propelled Crop Sprayer for Agricultural Sustainability in Small Farms

In most Asian countries, farmers have smallholdings ranging from one to two hectares. The tractor-mounted boom sprayers cannot practically be used in small size farms with divided plots and complex terrain. To cope with these issues, a prototype self-propelled crop sprayer was developed, including a 20-hp engine, 300 L liquid tank, and hydraulically-controlled spray boom with eight hollow cone nozzles. The spray symmetry of the hollow cone nozzle was evaluated under four pressures (2.5, 3, 3.5, and 4 bar) in the laboratory. The operating parameters of the sprayer, such as forward speed (4, 6, and 8 km h−1), spray height (40, 55, and 70 cm), and pressure (3, 5, and 7 bar) were optimized by measuring three spray characteristics including droplet density, coverage percentage, and Volume Median Diameter (VMD) in the cotton field. The results revealed that the nozzle spray was symmetrical at 2.5 and 3 bar pressure as the R2 value was higher than 0.96. The field test result showed that in all treatments, treatments T14 (6 km h−1, 55 cm, 5 bar) and T22 (8 km h−1, 55 cm, 3 bar) were suitable for spraying medium-to-low concentration solution (post-emergence herbicides and fungicides) and high concentration solution (insecticides and pre-emergence herbicides), respectively. The spray characteristics at treatments T14 and T22 were 64.7 droplets cm−2, 26.7%, 230 µm, and 39 droplets cm−2, 14.9%, and 219.8 µm respectively. The field efficiency of the sprayer was 61%. The spraying cost per unit area was 55–64% less compared to manual labor cost. In conclusion, a prototype self-propelled crop sprayer is an efficient and environment-friendly technology for small farms. Operating the sprayer at the optimal parameters also saves operational costs and time.

The influence of rotor downwash on spray distribution under a quadrotor unmanned aerial system

• Computational Fluid Dynamics model of sprays interaction with propeller airflow. • CFD model for multi nozzle/propeller crop sprayer, crosswind and forward flight. • Experimental validation of CFD model using a spray pattonator. • CFD model can be used to model the distribution of the spray’s impact with the crop. • Modelled distributions can be used for spray mission planners. • Spray distribution heavily effected by propeller downwash. • Higher propeller thrust leads to a peakier and less uniform distribution. This paper investigates how sprays are influenced by rotor downwash produced by a quadrotor Unmanned Aerial System when crop spraying. Computational Fluid Dynamics simulations, using RANS modelling for the flow field and Lagrangian particle tracking for the spray, are conducted for several single-rotor and multi-rotor cases with the spray injected underneath the centre of the rotor. The rotor is modelled using a Blade Element actuator disc model. The accuracy of the computational approach is demonstrated by good agreement with experiment for both thrust and deposited spray pattern for a single rotor in an indoor environment. Both the experimental and computational results show that the peak in the spray distribution under a single rotor increases as rotor thrust increases, whilst increasing the rotor height above the ground causes this peak to decrease. The validated Computational Fluid Dynamics method is then used to simulate flight conditions for single-rotor and multi-rotor cases. These show the existence of a critical flight speed, above which the spray impinging on the ground no longer contains a notable peak. This behaviour is seen to be due to the streamtube detaching from the ground and no longer carrying the spray directly to the ground plane. Above this critical speed the spray is seen to become suspended in the air behind the Unmanned Aerial System. This behaviour makes realistic simulation more difficult, as details of the ambient turbulence conditions would be needed to model the subsequent spray transport. The reliance on turbulence to transport the spray is undesirable from a practical point of view due to the increased likelihood of significant spray drift.

Parameter Optimization of Newly Developed Self-Propelled Variable Height Crop Sprayer Using Response Surface Methodology (RSM) Approach

The number of spray deposits plays an important role in effective and efficient spraying. The spraying equipment is one of the most significant factors that affect the number of spray deposits. Therefore, the study was focused on the parameter optimization of a newly developed self-propelled variable height crop sprayer. Response surface methodology (RSM) along with Box–Behnken design (BBD) was used to study the effect of the independent variables (forward speed, spray height, and spray pressure) on response variables such as droplet density, coverage per-centage, and Volume Median Diameter (VMD). The experiment was conducted in the cotton field. Additionally, the RSM model was validated in this research. The results revealed that the coefficient of determination (R2) values was good for all response variables in the quadratic polynomial model. The optimized parameters were 6.5 km/h, 60 cm, 4 bar for fungicide application, and 8 km/h, 70 cm, 3 bar for insecticide and herbicide application. The predicted response variable values at the optimal conditions were 60.4 droplet/cm2, 27%, 230 µm for fungicides and 37.8 droplet/cm2, 19.1%, 225.4 µm for insecticide and herbicides application. The model validation is confirmed by the mean of actual response variable values at the optimal condition for insecticide and herbicides application, which was 41.35 ± 3.67 droplet/cm2, 21.10 ± 1.72%, 227.43 ± 1.22 µm, and the prediction error was 8.46%, 9.2%, and 0.9% for droplet density, coverage percentage, and VMD, respectively. This study can provide support for further optimizing the parameters of the sprayer.

Smart tree crop sprayer utilizing sensor fusion and artificial intelligence

Delivering the appropriate amount of chemicals for each plant based on their needs is essential for reducing costs, waste, and labor. Smart agricultural machinery can provide variable-rate technologies using artificial intelligence (AI) and machine vision to optimize spraying applications. In this research, a low-cost smart sensing system for controlling airblast tree crop sprayers was designed and evaluated using citrus as a case study. The prototype comprised a LiDAR, machine vision, GPS, flow meters, sensor fusion, and AI to scan trees for tree height, tree classification, and fruit counting. Specifically, this smart sensing system can detect and classify objects to tree or non-tree (e.g., human, field constructions), measure tree height and canopy density, and detect and count fruit. Based on this information, it controls spraying nozzles to optimize spraying applications. A novel software was written in C++ and ran on an Nvidia Jetson Xavier NX embedded computer to process and control the data utilizing data fusion and AI techniques. The smart sensing system's results for tree height estimate indicated a relatively low average error of 6%. A convolutional neural network (CNN) was used to perform tree classification with an average accuracy of 84% in classifying the collected imagery into mature, young, dead, and non-tree objects. The fruit count module (also a CNN) had an F1 score of 89%, compared to ground-truth labeled images of mature and immature citrus fruits. Finally, the adoption of this new sensing method reduced spraying volume by 28%, compared to traditional spraying applications.

Design and Implementation of Low-Cost Field Crop Sprayer Electronic Flow Control System

The purpose of this research is to present the designs required and methodology of prototype production to control electronically a mechanical-controllable system on a case study. The system under consideration is a field crop sprayer. The reason for the investigation of this system is operator exposure to the harmful chemical and inefficiency of flow control. It is necessary to precisely start and end the chemical flow at the requested location, to close a certain part of the spraying line, and to prevent overdosing during the pulverization. An Arduino system was designed to control a precise electronic flow system. In this regard, Mechanical flow-control valves are equipped with 16 bar pressure-resistant and chemical resistant solenoid valves. Designs were produced and prototypes were presented. Low-cost sprayer control systems (SCS) chemical losses were reduced by 6% to 20%. The ergonomic design increased the productivity of the operator. Moreover, this system reduced fuel consumption by 2% to 6%. It is 40% more economical than existing systems. As a result, productive electronic control was achieved in the field crop sprayer.

Investigation of internal efforts in the components of the crop sprayer boom section

Purpose: Development results allow the defects in the boom section of a crop spraying machine design to be found, the most loaded structural components to be determined and the most suitable design parameters to be chosen. Design/methodology/approach: Results of theoretical investigation of internal forces distribution in the components of a boom section of a crop spraying machine in the static statement of the problem have been presented. The applied under discussion enables the static indeterminacy to be realized whilst calculating the complex frame structures though it requires not only considerable records of the function of potential energy of deformation (even without taking into account the function of potential energy of deformation of normal and lateral forces) but application of applied computer programs. The technique of static indeterminacy realization by minimum of potential energy of deformation (MPED) method has been used to calculate the framework. Findings: Technique of static indeterminacy realization by minimum of potential energy of deformation (MPED) method has been used to calculate the framework. The results of theoretical calculation and simulation of the boom section of a crop spraying machine have been compared. The results of analytical calculation have been checked by the simulation of 3D model of the using the program complex «Lira-SAPR», where the finite elements method (FEM) has been implemented. Research limitations/implications: Horizontal components of the shear forces as well as the normal forces and as a consequence the corresponding potential deformation energy are neglected, which has some effect on the accuracy of the calculations. Practical implications: An effective tool for strength analysis with preliminary assessment and diagnostics structures based on the constructed calculation models of stress strain state load-bearing frames of typical geometry with an arbitrarily given distribution of external load. Originality/value: A universal algorithm records of the function of torque and bending moment, as well as the function of potential deformation energy of a spraying machine boom section.

PBTK model for assessment of operator exposure to haloxyfop using human biomonitoring and toxicokinetic data

Physiologically-based toxicokinetic (PBTK) models are mathematical representations of chemical absorption, distribution, metabolism and excretion (ADME) in animals. Each parameter in a PBTK model describes a physiological, physicochemical or biochemical process that affects ADME. Distributions can be assigned to the model parameters to describe population variability and uncertainty. In this study to assess potential crop sprayer operator exposure to the herbicide haloxyfop, a permeability-limited PBTK model was constructed with parameter uncertainty and variability, and calibrated using Bayesian analysis via Markov chain Monte Carlo methods. A hierarchical statistical model was developed to reconstruct operator exposure using available measurement data: experimentally determined octanol/water partition coefficient, mouse and human toxicokinetic data as well as human biomonitoring data from seven operators who participated in a field study. A chemical risk assessment was performed by comparing the estimated systemic exposure to the acceptable operator exposure level (AOEL). The analysis suggested that in one of the seven operators, the model estimates systemic exposure to haloxyfop of 49.04 ± 10.19 SD μg/kg bw in relation to an AOEL of 5.0 μg/kg bw/day. This does not represent a safety concern as this predicted exposure is well within the 100-fold uncertainty factor applied to the No Observed Adverse Effect Level (NOAEL) in animals. In addition, given the availability of human toxicokinetic data, the 10x uncertainty factor for interspecies differences in ADME could be reduced (EFSA, 2006). Thus the AOEL could potentially be raised tenfold from 5.0 to 50.0 μg/kg bw/day.

Design optimization and test for a pendulum suspension of the crop sprayer boom in dynamic conditions based on a six DOF motion simulator

Design optimization and test for a pendulum suspension of the crop sprayer boom in dynamic conditions based on a six DOF motion simulator

Field-crop-sprayer potential drift measured using test bench: Effects of boom height and nozzle type

Because of variations in environmental conditions, spray-drift field measurements following ISO 22866:2005 involve complicated and time-consuming experiments often with low repeatability. Therefore, simple, repeatable, and precise alternative drift assessment methods that are complementary to the official standards are required. One of the alternatives is the use of a drift test bench for field crop sprayers. Previous studies have demonstrated that the drift test bench can be considered an adequate complement to existing standard protocols for field drift measurements. In this study, in order to further improve the methodology and to evaluate the possibility of classifying different field-crop-sprayer settings according to drift risk using a test bench, a series of tests were performed in a test hall. A conventional mounted Delvano HD3 crop sprayer (Delvano, Kuurne, Belgium) equipped with an 800-l spray tank and a 15-m-wide stainless steel spray boom was used. Eight different sprayer setups were tested, involving three nozzle types (TeeJet XR 110 04, Agrotop TDXL 110 04 and Micron Micromax 3) and three boom heights (0.30, 0.50, and 0.70 m). For the drift classification, the reference sprayer drift behaviour was defined as that obtained using conventional flat fan TeeJet XR 110 04 nozzles operated at 0.30 MPa and at a boom height of 0.50 m. The different sprayer setups were successfully assigned to different drift reduction classes, and the results underlined the effects of nozzle type and boom height on the potential drift. The feasibility of the test-bench methodology for classifying field-crop-sprayer drift according to ISO 22369-1:2006 was demonstrated.

Performance of a Field Crop Sprayer Nozzle Used in Bangladesh

This study was carried out during the period from July'97 to May 99 in the department of Farm Power and Machinery, Bangladesh Agricultural University, Mymensingh. Naboti 910M was tested to evaluate its performances in the laboratory. The discharge increased significantly with the increase in pressure. The relationship between discharge and pressure was y = 470.58x0.377. The angle of sprays increased significantly with the increase in pressure from 1 to 4 kg/cm² and then the spray angle changed with increasing pressure. They were statistically identical. The relationship between spray angle and pressure was y = 88.17x0 .130. Curves of spray distribution flattened with increasing nozzle height, pressure and wind speed. Spray liquid distribution uniformity increased significantly with the increasing of nozzle height, pressure and wind speed. The nozzle showed 64.99% distribution efficiency at an interaction effect of pressure 6 kg/cm², nozzle height 60 cm and wind speed 2 m/s. Deposition decreased with the increase nozzle height and wind speed. The distribution uniformity of spray increased with increasing pressure and nozzle height. The lowest uniformity was found at 15 cm height and the highest uniformity was found at 60 cm of nozzle height at constant pressure. Distribution uniformity increased with increasing nozzle inclination from oº until it reached at 60° and then distribution uniformity decreased rapidly. The lowest value of distribution uniformity was 15.727% and it was found at combined effect of pressure 1 kg/cm² and nozzle height 15 cm and nozzle inclination. The highest value of distribution uniformity was 52.087% and it was found at combined effect of pressure 6 kg/cm² and nozzle height 60 cm.

Segurança na aplicação de agrotóxicos em cultura de batata em regiões montahosas

O presente estudo objetivou a quantificação das exposições na aplicação de agrotóxicos com o pulverizador convencional usado pelo produtor em cultura de batata em regiões montanhosas; a determinação das regiões do corpo dos trabalhadores mais expostas; a avaliação da eficiência de medidas de proteção individuais e coletivas; e a classificação das condições de trabalho quanto à segurança das recomendações de agrotóxicos registrados para o controle das principais pragas e doenças dessa cultura. Concluiu-se que a maior exposição ocupacional ocorreu na via dérmica; o trabalhador sofreu maior exposição com a utilização do pulverizador do produtor; o Knapik foi a medida de segurança coletiva mais eficiente no controle da exposição do trabalhador e a individual mais eficiente foi a Roupa Unesp; os membros inferiores foram as regiões do corpo mais exposta às caldas; sem a utilização das medidas de segurança, as 54 recomendações de agrotóxico para a essa cultura foram classificadas como inseguras para o trabalhador; todavia, com a utilização do protótipo de barra manual, apenas duas tornaram-se seguras; com o pulverizador Knapik, somente três; nove com o AZR; e dezesseis com a Roupa Unesp.

Design Optimisation for the Vertical Suspension of a Crop Sprayer Boom

The dynamics of a vertical suspension for a 39 m wide boom on a John Deere crop sprayer was optimised. The optimisation was based on a mathematical model of the suspension with an existing non-linear Koni® damper characteristic. During the optimisation, several tracks, which are based on power spectral densities of measurements in different field conditions, are applied to the suspension. The objective function to be minimised is the standard deviation of the absolute boom rotation around the horizontal axis while applying the tracks. As the model is simple but accurate, computation time is small such that many different field situations can be imposed during optimisation. By playing with the distance to the rotation point of the damper and selection of the appropriate damping value, the optimum could be realised.

Avaliação do nível de ruído causado por diferentes conjuntos mecanizados

O presente estudo busca avaliar e comparar os níveis de ruído durante uma operação agrícola, desde a fase de aragem do terreno, até a colheita, para que, assim, em situação real de trabalho no campo, sejam feitas as devidas análises dos riscos a que estão sujeitos os operadores de máquinas, durante todo o manejo de uma cultura. Para realização dos ensaios, foram utilizados: trator (73cv), arado e grade de discos, aplicador de calcáreo, pulverizador e colhedora, onde foram feitos testes com o trator, tracionando cada um dos implementos, em velocidade e operações diferentes, com o motor mantido na rotação de 1700 rpm. Para a colhedora, foram utilizadas, também, velocidades de avanço diferentes, avaliando-se o nível de ruído à esquerda e à direita do operador. Em relação às médias dos níveis de ruído, os valores se encontraram muito elevados, ultrapassando os limites estipulados, gerando grande desconforto ao operador. A colhedora apresentou maior desconforto ao operador, não apresentando diferença significativa entre a mesma, parada ou em movimento. Mesmo estando o trator e/ou colhedora parados, os mesmos apresentaram níveis de ruído bem superior, ao mínimo estipulado apresentando assim, risco não só a quem opera, como também a quem está próximo dos mesmos.

CONTROL OF CABBAGE LOOPER, DIAMONDBACK MOTH AND IMPORTED CABBAGEWORM ON CABBAGE WITH MICROBIAL INSECTICIDE SPRAYS, 1998

CONTROL OF CABBAGE LOOPER, DIAMONDBACK MOTH AND IMPORTED CABBAGEWORM ON CABBAGE WITH MICROBIAL INSECTICIDE SPRAYS, 1999: 'Bravo' cabbage was planted in 1 row plots 35 ft. long on 26 Jul. Plants were spaced 22 inches apart in the row with 64 inches between rows. The treatments were arranged in a RCB design with 4 replications. The soil was a Norfolk A loamy sand. All spray treatments were mixed in 2.0 gal of water and applied with a custombuilt row crop sprayer. Each row was covered by 6 drop nozzles delivering 50 gpa at 30 psi. Treatments were applied on 18, 25 Aug, 1, 9, 14 and 23 Sep. Foliage injury was rated on a 1-6 scale as follows: 1= no apparent insect feeding; 2= minor insect feeding on wrapper or outer leaves, 0-1% leaf area eaten; 3= moderate insect feeding on wrapper or outer leaves with no head damage, 2-5% leaf area eaten; 4= moderate insect feeding on wrapper or outer leaves with minor feeding on head, 6-10% leaf head unmarketable during normal marketing conditions; 5= moderate to heavy feeding on wrapper and head leaves and moderate number of feeding scars on head, 11-30% of leaf area eaten 6= considerable insect feeding on wrapper and head leaves with head having numerous feeding scars, over 30% of leaf area eaten.

Control of Cabbage Looper, Diamondback Moth, and Imported Cabbageworm on Cabbage with Mi-Crobial Insecticides, 1997

Abstract ‘Bravo’ cabbage were planted in 35-ft-long 1-row plots on 19 Aug. Plants were spaced 22 inches apart in the row i with 72 inches between rows. The treatments were arranged in a RCB design with 3 replications. The soil was a Norfolk “A” loamy sand. All spray treatments were mixed in 2.0 gal of water and applied with a custom-built row crop sprayer. Each row was covered by 6 drop nozzles delivering 50 gal/acre at j 30 psi. Treatments were applied on 8, 15, and 22 Sep and 1, 7 Oct. Foliage injury was rated on 1-6 scale as follows: 1) no apparent insect feeding; 2) minor insect feeding on wrapper or outer leaves, 0-1% leaf area eaten; 3) moderate insect feeding on wrapper or outer leaves with no head damage, 2-leaf area eaten; 4) moderate insect feeding on wrapper or outer leaves with minor feeding on head, 6-10% leaf head unmarketable during normal marketing conditions; 5) moderate to heavy feeding on wrapper and head leaves and moderate number of feeding scars on head, 11-30% of leaf area eaten; 6) j considerable insect feeding on wrapper and head leaves with head having numerous feeding scars, over 30% of leaf area eaten.

Control of Cabbage Looper, Diamondback Moth, and Imported Cabbageworm on Cabbage with Pyrethroid Insecticides, 1997

Abstract ‘Bravo’ cabbage were planted in 35-ft-long 1-row plots on 31 Jul. Plants were spaced 22 inches apart in the row with 72 inches between rows. The treatments were arranged in a RCB design with 3 replications. The soil was a Norfolk “A” loamy sand. All spray treatments were mixed in 2.0 gal of water and applied with a custom-built row crop sprayer. Each row was covered by 6 drop nozzles delivering 50 gal/acre at ] 30 psi. Treatments were applied on 20 and 27 Aug; 5, 22 Sep and 1, 7 Oct. Foliage injury was rated on 1-6 scale as follows: 1) no apparent insect feeding; 2) minor insect feeding on wrapper or outer leaves, 0-1% leaf area eaten; 3) moderate insect feeding on wrapper or outer leaves with no head dam-1 age, 2-5% leaf area eaten; 4) moderate insect feeding on wrapper or outer leaves with minor feeding on head, 6-10% leaf head unmarketable during nor- j mal marketing conditions; 5) moderate to heavy feeding on wrapper and head leaves and moderate number of feeding scars on head, 11-30% of leaf area 1 eaten; 6) considerable insect feeding on wrapper and head leaves with head having numerous feeding scars, over 30% of leaf area eaten.

Colorado Potato Beetle Control on Potatoes with Foliar Insecticide Sprays, 1997

Abstract Kennebec’ potatoes were planted in 20-ft rows on 4 Apr. Plots consisted of a single treatment row. The distance between rows was 64 inches and the distance between plants within the row was 10 inches. Plots were arranged in RCB design with 4 replications. The soil was a Norfolk “A” loamy sand. All spray treatments were mixed in 1.5 gallons of water and applied with a custom-built compressed-air row crop sprayer. Each row was covered by 6 drop nozzles delivering 50 gpa at 30 psi. All plots were treated 28 May and 1, 10 Jul. Novodor plots were sprayed again on 5 and 18 Jun. Agri-Mek and Provado WG received a second application on 18 Jun. On 1 and 10 Jul the Agri-Mek and Novodor plots were sprayed with Provado 1.6 E at the rate of 0.047 lb (AI)/acre. The Agenda plots; were treated on 16 Jul. In evaluating the treatments, direct counts of the number of Colorado potato beetle adults, larvae, egg masses per 10 plants and % defoliation were recorded. Because of excessive soft rot, yields were not recorded.