To give you a better idea on how to get the best value for your money, here’s an overview of the tire and wheel options available for center-pivot systems.

No-flat solutions

Plastic tires – Manufacturers offer roto-molded plastic tires made of high-density poly. These tires simply bolt onto the irrigation system’s existing rims, eliminating the need to purchase rims with the tires, although they can be purchased as assemblies for quick unbolt/rebolt.

The main benefit of plastic tires is they never go flat. Not only does this save time repairing flats, but it also eliminates crop damage from bringing in service equipment to repair those flats.

Another advantage of this tire is its non-directional tread design, which allows it to be used universally in circles or wipers.

Plastic tires are fully UV-treated, allowing them to last longer than rubber, according to lab testing. The plastic concept is fairly new, but accelerated testing has proved a 10-plus-year life span is common for these types of tires.

They have a mid-range cost, comparable to that of a domestically manufactured rubber bias tire.

One of the main downfalls of plastic tires, however, is the tendency to cause ruts in heavier soils saturated with water. As a result, they’re not generally recommended for high-water applications or heavy, gumbo soils, where they may dig in more than rubber tires due to their relative inflexibility.

Additionally, plastic tires are somewhat limited in the number of sizes available. They can be found for most standard rims but are not always offered for specialty rims.

Steel wheels – Another no-flat option is steel wheels. Understandably, they have a higher up-front cost since the farmer has to purchase an entire wheel rather than just the rubber or plastic to go on an existing rim.

Additionally, there are several issues commonly associated with steel wheels. Welds may break, the wheels can rust, and customers often experience longer lead times.

Nonetheless, the solid-steel construction allows them to stand up well to heavy applications such as corner arms. Some farmers swear by steel, while others have had poor experiences, making it difficult to recommend this product across various applications.

In the end, the decision to go with steel wheels generally comes down to personal preference.

Tracks – There are two types of tracks for irrigation systems: over-the-wheel (available in plastic and metal) or complete track systems, which replace the entire wheel assembly.

Over-the-wheel tracks, which are installed over the existing tires, are only available on certain types of tires – particularly recaps, which have limited availability.

Track systems have the largest footprint and offer the most flotation when working in difficult soil conditions. However, they are the most expensive option on the market.

In addition to the high purchase price, track users can expect to pay more for maintenance because track systems have a lot of moving parts.

Depending on the amount of use, some users have to replace wear parts every three to four years. If over-the-wheel tracks are used, the moving parts and rubber tires are also subject to wear and air leakage.

Pneumatic-tire solutions

Bias tires – The most common tire option on irrigation systems is bias tires. All irrigation manufacturers offer bias tires as standard equipment.

These are the least expensive tire option, and they are available in many sizes to accommodate standard rims as well as larger specialty rims used for increased flotation and heavier loads.

Rubber tires are also sold in assemblies, which are very handy to have on hand to quickly unbolt and rebolt during irrigation season.

There are a wide variety of manufacturers who make bias tires. Domestically manufactured tires can be up to 30 percent more expensive than imports. In the past, domestic tires typically came with better warranties and warranty support, but in recent years import tire quality has improved. In fact, certain import brands now offer five-year warranty and domestic warranty support.

Recap or retread tires were more common in the ’70s and ’80s. Back then, there was a greater supply of good-quality tire casings from the trucking industry that were being recapped for use on irrigation systems.

As tire technology has improved over the years, tire carcasses now have many more miles (from extended use in the trucking industry), making the recaps less dependable in the field.

There is a trend toward lower-profile wider tires in the trucking industry, which also limits availability. As a result, few suppliers sell recap tires competitively today.

Despite which type of bias tire is used, air is a big disadvantage, since a flat tire can cost a lot of money in repair and downtime.

They generally require tubes, which add cost. Another drawback is the lack of flotation due to higher inflation pressure needed to keep the bead seated. Because of the old technology found in bias tires, flotation is reduced as the tires are inflated and lose footprint.

Radial tires – Radial tires take advantage of modern tire technology. They run at a lower psi, keeping the tread face flat on the ground to maximize their footprint, traction and flotation. Because radial tires flex, the tire cleans out better than bias tires.

Radial tires are constructed with tighter bead tolerances so they can be run at lower air pressure without the risk of bead breaks, eliminating the common problem of bead leaks in pivot tires. Also, manufacturers offer warranties up to eight years for radial irrigation tires.

Cost is a main deterrent of purchasing radial tires. They are higher-priced than bias tires and approximately 10 percent more expensive than plastic no-flat tires.

The other disadvantage is they are pneumatic, so there’s still the potential to go flat, even though they are constructed much stronger than traditional bias tires.

Now you know (sort of)

After understanding these five types of irrigation tires, the next step is to work with trusted suppliers who can help you determine the best option for your operation.

They can help you reach the right decision based on a combination of factors, including soil types and local farming practices.  FG

Loren Block is the marketing manager for Dawson Tire & Wheel.