Three-Point Sprayers: A Beginners Guide

A 3-point sprayer is a type of agricultural sprayer designed to be mounted on the three-point hitch of a tractor. These sprayers are commonly used for crops, large gardens, pastures, and other fields due to their versatility, simplicity, and relative cost.

The primary defining aspect of a 3-point sprayer is the way it attaches to the tractor. Unlike pull-type sprayers, skid sprayers, or self-propelled sprayers, they connect to the rear 3-point arms of the tractor. The tractor provides the power for the pump, either PTO or hydraulic, and also lifts the boom.

At one time, 3-point sprayers were widely used in large-scale agriculture, but over the decades, the sizes of farms have increased, and the need for larger pull-behind or self-propelled sprayers has taken over. 3-point sprayers still have their place, but they are limited in their functional size because they rely on the tractor’s 3-point lift system to be able to safely handle the weight.

Basic Three-Point Sprayer Setup

A basic three-point sprayer mounts to the back of a tractor using the three-point hitch and is powered by either the PTO or a hydraulic-driven pump, although a 12-volt pump can be used. It includes a tank (usually 25 to 300 gallons), a pump to pressurize the liquid, and either a spray boom or boomless nozzles to apply it.

Booms have multiple nozzles spaced evenly for wide, even coverage, while boomless setups use one or two nozzles for spraying rough or tight areas. A pressure regulator controls flow, and a gauge helps monitor it.

The system is plumbed with chemical-resistant hoses and may include a filter and an agitator to keep the mix uniform. It’s a simple, effective setup for spraying fields, lawns, or pastures.

3-Point Sprayer Diagram

Key Components of a 3-Point Sprayer

• Tank: The tank of a 3-point sprayer typically holds between 100 and 300 gallons of liquid, depending on the size of the tractor.
• Three-Point Hitch: These are the connection points that secure the sprayer to the tractor’s three-point hitch.
• Pump: Common types of pumps used in 3-point sprayers include roller pumps and centrifugal pumps. You can also find diaphragm pumps on a 3-point sprayer, but they are less common.
• Plumbing: This includes all the necessary hoses and fittings that transport the liquid from the tank to the sprayer boom or nozzle.
• Sprayer Boom: The boom is typically 20 to 30 feet wide, although the size can be limited by the size of the tractor it is mounted on.

Advantages of a 3-Point Sprayer

• Compact and Maneuverable: The compact design of a 3-point sprayer makes it easy to maneuver and store.
• Simplicity and Lower Cost: These sprayers are simpler and often less expensive than pull-type sprayers. The tractor powers the pump via the PTO (Power Take-Off) or hydraulic system.
• Versatility: Many 3-point sprayers come with a roll of hose and a hand trigger wand, allowing for spot spraying in hard-to-reach areas like ravines, ditches, and around trees.
• Ease of Control: Controls for the sprayer can be easily mounted within reach of the tractor operator, making it user-friendly. While electronic controls and valves can be added, manual controls are often preferred to keep costs low and operations simple.

Disadvantages of a 3-Point Sprayer

• Limited Size and Capacity: The tank size is limited by the carrying capacity of the tractor. Smaller tractors may struggle with even a 100-gallon tank due to weight constraints.
• Limited Boom Width: The width of the sprayer boom is also limited, as it must be sized according to what the tractor can safely handle.
• Manual Operation: Smaller 3-point sprayers may not have hydraulic cylinders to open and close the booms automatically, requiring you to physically move the boom arms from the transport to the spraying position.

Common Uses of a 3-Point Sprayer

3-point sprayers are versatile and can be used for a variety of applications:

1) Row Crops

Typical goal: pre-plant burndown, early post-emerge herbicide, foliar feeds, and in-season fungicide passes on corn/soy/small grains or food-plot crops.

Example 3-Point Sprayer Setup for Row Crops:

• Target: ~10–15 GPA, 6–9 mph, 35–50 PSI, depending on nozzle/orifice
• Tractor: ~55–75 hp, Category II 3-pt
• Sprayer: 250–300 gal poly tank, 30–40 ft boom with 20″ spacing
• Pump: PTO roller or centrifugal with bypass regulator
• Nozzles: AIXR 11003 or 11004 for coarse-to-very-coarse droplets to help with drift (swap to twinjet for canopy penetration on fungicide)

2) Lawns & Turf (large lawns, sports fields, golf)

Typical goal: even coverage for broadleaf control, pre-emergent, foliar iron, and fungicides.

Example 3-Point Setup for Turf:

• Target: 0.4–1.0 GPA/1,000 sq ft (≈ 17–44 GPA) depending on product; 4–6 mph, 30–45 PSI
• Tractor: 25–40 hp compact utility
• Sprayer: 150–200 gal, foam marker or GPS lightbar
• Boom: 20–30 ft with drift-guarded flat fans
• Nozzles: AIXR 11002/110025 for coarse droplets that still give a clean pattern on short turf
• Pastures: Useful for managing pastures. Especially 3-point sprayers equipped with boomless nozzles.

3) Pastures (with emphasis on boomless)

Typical goal: broadleaf control, brush edges, spot-treating problem patches, covering rough ground fast.

Example 3-Point Sprayer Setup for Pastures (Boomless):

• Tractor: 40–60 hp, good rear ballast (full tank weight swings handling)
• Sprayer: 200–300 gal with one or two boomless tips on a center mount bar
• Nozzles: Boomless (e.g., 30–40 ft effective width per pair) with coarse/very-coarse droplets
• Target: 12–20 GPA, 5–8 mph, 35–60 PSI depending on nozzle and width

3-Point Sprayer Operation

3-point sprayer controls can be set up in several ways. They range from simple manual controls to more sophisticated options that provide more convenience, but these are more expensive. Let’s look at the basic control aspects.

Controls

The simplest way to control a 3-point sprayer is to use manual on/off valves paired with a pressure-regulating valve. This setup eliminates the need for electronic controls or automated systems, keeping costs low and maintenance minimal. This article on sprayer control provides a detailed breakdown. However, you may want to use larger plumbing to accommodate higher flow rates than the lawn sprayer shown in the article.

3-Point Sprayer Pumps

PTO-driven pumps are a natural fit for 3-point sprayers because they leverage the tractor’s existing Power Take-Off (PTO) system to drive the pump.

Roller and centrifugal pumps are the most common PTO-driven options for 3-point sprayers. Roller pumps are affordable and versatile, handling herbicides, pesticides, and fertilizers with flow rates up to 20 GPM and pressures around 300 PSI. They are compact but require regular maintenance for roller wear.

Centrifugal pumps, known for high flow rates (up to 200 GPM), are ideal for large booms, but they do offer lower pressure (up to about 60 PSI).

PTO-driven pumps are popular for their reliability, simplicity, and compatibility with tractor power, making them ideal for several different spraying tasks.

How Much Area Can a 3-Point Sprayer Cover?

The area a 3-point sprayer can cover depends on several factors, including the tank capacity, the spray boom width, and the application rate. Here’s a general approach to estimate the coverage:

1. Tank Capacity: This is typically measured in gallons. Common sizes for 3-point sprayers range from 50 to 300 gallons.
2. Boom Width: The width of the boom determines how wide an area can be covered in one pass. Boom widths can vary, often ranging from 10 to 30 feet or more.
3. Application Rate: This is the amount of liquid applied per unit area, typically measured in gallons per acre (GPA). This rate depends on the type of spray nozzles, pressure, and speed of the tractor.

Calculating Coverage

1. Determine the Application Rate: Assume you are applying at a rate of 20 GPA (a common rate for herbicides).
2. Calculate Tank Coverage: If you have a 100-gallon tank, the area covered per tank is:
   • Area Covered= Tank Capacity/Application Rate = 100 gallons/20 GPA = 5 acres
3. Consider Boom Width and Tractor Speed: How fast you can cover this area is another aspect to consider. Efficiency can be influenced by the boom width and the tractor’s speed.

For more details, take a look at this guide on how much area different sprayer sizes can cover.

Key Takeaways

A 3-point sprayer is a practical and economical choice for many agricultural and landscaping needs. Its compact design, ease of use, and cost-effectiveness make it a valuable tool for farmers and gardeners alike. However, the limitations in tank and boom size, as well as some manual operations, should be considered when choosing the right sprayer for your needs.