Inputs

Target Crop: The default is citrus. As of November 2021, only citrus tree model was available in the model.

Mean Tree/Row Height: This is the average height of trees or row measured from the ground. The model assumes that the upper spray nozzles are adjusted to tree or row height.

Skirt Height: This is the average height of the base of the tree canopy measured from the ground. The model assumes that the lower spray nozzles are adjusted to skirt height.

Canopy Diameter: This is the distance from canopy boundary to canopy boundary across the row. For well spaced trees, the model assumes that the canopy is symmetric around the trunk axis.

Foliage Density: This is a measure of how much foliage area is available in the tree canopy and can be estimated qualitatively. The model uses fixed average values based on actual measurements as follows: 3.0 m²/m³ for low, 3.8 m²/m³ for medium, and 5.4 m²/m³ for high density.

Trees per Row: This is the number of trees in a single row including missing trees, if any. The model simulation assumes that spray is continuously applied from start to end of row, as in conventional application.

Number of Rows: This is the number of tree rows to be sprayed.

Tree Spacing: This is the distance from tree trunk to tree trunk within a row.

Row Spacing: This is the distance from tree trunk line in one row to tree trunk line in an adjacent row.

Number of Missing Trees: This is the number of missing trees in all rows of the application area.

Air Temperature: This is the air temperature at the time of application. Increasing air temperature increases the rate of spray droplet evaporation.

Relative Humidity: This is the relative humidity at the time of application. Increasing relative humidity decreases spray droplet evaporation which reduces spray drift potential.

Wind Speed: This is the wind speed at the time of application. Increasing wind speed increases spray drift potential.

Sprayer: The default is Rears Power Blast - PTO. As of November 2021, the parameters for only this sprayer were in the model.

Nozzle type/side: The first input (dropdown menu) is the type of nozzle. The default is Disc-core. The second input (text field) is the total number of open nozzles on each side of the sprayer.

Upper: This is the upper nozzle size (dropdown menu) and number of upper nozzles (text field) on each side of the sprayer.

Lower: This is the lower nozzle size (dropdown menu) and number of lower nozzles (text field) on each side of the sprayer.

Operating pressure: This is the indicated operating pressure of the sprayer from a properly functioning pressure gauge.

Ground speed: This is the calibrated ground travel speed of the sprayer.