Spray Hoods Evolve

Reconfigured Accessories Can Help Win Battle Against Dicamba Drift

Jim Patrico
By  Jim Patrico , Progressive Farmer Senior Editor
The 642E hooded spray rig attaches to a tractor's three-point hitch and folds in the center. It comes in 30- and 40-foot-wide models. (Progressive Farmer photo courtesy of the manufacturer)

Roundup brought Steve Claussen into the hooded-sprayer business more than 20 years ago. But his company, Willmar Fabrication, probably has never been busier making hoods than it is now. Dicamba and 2,4-D have made hoods a hot item.

The inventive Claussen and his brother Robert created Redball Hooded Sprayers in the early 1990s as "chemical cultivation" tools to spray Roundup between rows of cotton while protecting the crop from overspray. With the advent of Roundup Ready Flex cotton, the hoods morphed to a torpedo shape to lift and separate the canopy to spray multiple herbicides on weeds below.


With dicamba and 2,4-D-resistant crops on the scene, Redball hoods have morphed again, this time into a tool to fight drift.

Instead of running between the rows, broadcast hoods now cover the crop. Nozzle tips under the hoods apply chemicals to the crop, and the rounded poly structures prevent most droplets from escaping into the atmosphere to do damage to nearby sensitive plants. The first Redball broadcast hoods appeared in 1993. After some recent tweaks to better control drift, Generation II hoods appeared in 2013.

Those hoods became part of two-year field trials conducted at the University of Nebraska and at Mississippi State University in 2015-16. The trials compared the amount of chemical drift when using an open boom sprayer versus using a hooded sprayer in similar wind conditions. Researchers used a variety of spray tips in a sequence of runs over a 600-foot-long field. Result: a marked reduction of drift with hoods compared to open booms.

"It's really clear from this study that we have a tool [hoods] that can significantly reduce drift. It's one of those tools that will help us in the [current challenging] application situation," says weed scientist and application technology specialist Greg Kruger, who led the trials in Nebraska.

Any reduction in drift is good news to growers and applicators when applying dicamba or 2,4-D products near sensitive areas. While hoods can be great tools, it's important to remember that it will take a whole toolbox to defeat drift, Kruger says: "Application systems are complex, and there is not going to be a silver bullet for any technology, so we are going to stack all kinds of technologies to optimize those systems."


Tweaking Redball's broadcast hood designs was tricky, Claussen says. "We tried to close every possible crack or opening so wind couldn't gather a droplet of spray and take it out of the hood."

To further contain droplets, engineers also lengthened the wind curtains that hang from the hoods. They now touch the crop canopy to create a kind of sealed enclosure.

Claussen had new herbicide-tolerant technologies like dicamba and 2,4-D in mind with the new design. Redball needed to accommodate the angle and ultracoarse spray pattern they required. "For the TTI [Turbo TeeJet Induction] tips, we had to make a special bracket because the spray comes out tilted. We had to change the angle of where the nozzle body comes into the hood," he says.

Because hoods are so effective at reducing drift, Claussen says, they are ideal for using near buffer strips. Hoods also can give better coverage, waste less product and, in the end, are more cost effective than open boom sprayers. If a hooded system were to prevent one drift-related accident, it could pay for itself immediately in saved damage or even legal bills, Claussen says.

Of course, farmers and applicators should always follow the label for any herbicide product.


Hoods do have their drawbacks, including time efficiency. The current widest version of Redball hoods is 60 feet for the SPK645 retrofit kit for self-propelled sprayers. While that is plenty wide for many situations, it could make for longer days compared to 90- or 120-foot booms.

The 60-foot limit is due in part to weight issues. The SPK645 covers only the inner boom sections of a 90-foot machine. The outer boom sections, Claussen explains, are made of lighter materials and might not have the strength to support hoods weighing about 9 pounds per linear foot. Also, having hoods all the way to the end boom sections could restrict folding and make the vehicle too wide for transport.

In most field situations, Claussen says, open outside booms will spray in tandem with hooded inner sections to give the full 90-foot spraying width.


Thorough cleanout between chemicals is critical in the dicamba era to avoid accidental contamination and possible crop damage. Hoods add an extra step to that cleanout process. The poly in the hood is very smooth, Claussen says, but it does catch mist and has to be power-washed after using products like dicamba. That cleaning process is equivalent, he says, to having to clean the outside of the sprayer or tractor, which also collect mist and dust.

The extra time and effort might discourage some. But Claussen suggests that an ideal solution would be to dedicate a hooded sprayer to apply dicamba products only, especially around sensitive areas.

In the end, some farmers and applicators will opt out of hoods because it's just one more thing to deal with. Others will see hoods as a worthwhile investment in time and money to reduce potentially damaging drift.


The SPK645 comes in 20-inch segments that can be bolted together to fit almost any commercial self-propelled sprayer. Aluminum brackets mount to the sprayer's frame, and the hoods slip onto the brackets. It takes about 10 hours to install a 60-foot system. But once installed, the hoods are easy to remove or reinstall in only 10 to 15 minutes.

When properly installed, the hoods don't affect a self-propelled sprayer's plumbing and rate controls, or auto boom height and anti-sway functions, Claussen says. Operators don't have to reduce ground speed because of hoods.

Cost of a 60-foot SPK645 kit is $17,500.

Redball hoods also come as complete tractor-mounted packages.

"I consider this our best buffer or small-acreage machine," Claussen says of the tractor-mounted 642E model, which comes in 30- and 40-foot widths.

The 642E models come with a 300-gallon materials tank and a 9-gallon freshwater safety tank. They also have all the necessary plumbing except spray tips, screens and caps. Triple nozzle bodies are included and employ a 1/2-inch quick-attach diaphragm.

Controllers on the boom are solenoid and manual, with optional in-cab pressure adjustment capability. Spray height is adjustable with gauge wheel settings.

The 642E folds in the center, and Redball offers an optional trailer hitch for easy towing. Travel widths are 18 feet, 6 inches and 21 feet, 9 inches. Travel heights are 11 and 13 feet. The larger 642E model sells for about $21,500.

Jim Patrico