Orchard Spray Rates
How to Determine the Amount of
Pesticide and Water to Use in Your Orchard

Bulletin 892-01

Examples for Review

To help review the information presented in the last few pages, here is a series of four sample calculations, all based on Provado 1.6F insecticide, which is labeled for application to apples for leafminer control at a dilute rate of 2 fluid ounces per 100 gallons. The Provado label does not state a rate per acre.

Example 1: How much Provado 1.6F should a grower use per acre for an orchard of big old apple trees, for a dilute application, if these trees require 400 gallons of water per acre to the point of runoff?

(dilute rate) x (dilute volume) = (amount of product per acre)   2 oz. 100 gal. water x 400 gal. water acre = 8 oz. per acre

Example 2: How much Provado 1.6F should a grower use per acre for an orchard of semidwarf apple trees, for a dilute application, if these trees require 180 gallons of water per acre to the point of runoff?

(dilute rate) x (dilute volume) = (amount of product per acre)   2 oz. 100 gal. water x 180 gal. water acre = 3.6 oz. per acre

Example 3: How much Provado 1.6F should a grower use per acre for an orchard of semidwarf apple trees, for a concentrate application, if these trees require 180 gallons of water per acre to the point of runoff, and the grower's airblast sprayer uses 60 gallons of water per acre? And what concentration is this?

(dilute rate) x (dilute volume) = (amount of product per acre)   2 oz. 100 gal. x 180 gal. acre = 3.6 oz. per acre   dilute volume concentrate volume = concentration     180 60 = 3 This is a 3X concentration.

You might have noticed that the block of semidwarf trees used in Examples 2 and 3 required the same amount of Provado per acre for either a dilute or a concentrate application, but the amount of water used per acre was different for the two types of applications.

Example 4: How much Provado 1.6F should a grower use per acre for an orchard of semidwarf apple trees, for a concentrate application, if these trees are in rows 18 feet apart, the tree canopy width is 10 feet, and the tree height is 10 feet? And what spray concentration is used when an airblast sprayer applies 85 gallons per acre?
First, check the chart on page 19. For 18-ft. rows and trees 10-ft. wide and 10-ft. tall, your dilute volume would be 169 gallons per acre.

dilute volume = 169 gal. per acre, based on the chart on page 19

For the final step multiply (the dilute rate by the grower's dilute volume to determine the amount of pesticide to use per acre.

(dilute rate) x (your dilute volume) = amount of product per acre   2 oz. 100 gal. x 169 gal. acre = 3.4 oz. per acre

Another way to do the final step is to note in the tree-row volume chart that the trees are 42% of standard. Then take 42% of the full rate of Provado.

amount of pesticide per 100 gal. water x standard dilute volume of water per acre = full rate of pesticide per acre   2 oz. per 100 gal. water x 400 gal. water per acre = 8 oz. per acre (the full rate)

42% of the full rate: (8 oz. per acre) x (0.42) = 3.4 ounces per acre

The concentration is 169 gallons per acre divided by 85 gallons per acre which equals approximately 2, so it is a 2X application.

dilute volume concentrate volume = concentration   169 gal. per acre 85 gal. per acre = approximately 2 This is a 2X concentration.

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