The Wet Blade is rotary cutter in which herbicides are metered precisely out of the hub of the blade (Figure 24). The blade is similar to a lawn mower blade but has an aerodynamic design that holds fluid along the cutting edge even while the blade is spinning. Coupled with the blade is a radar gun to monitor equipment speed, a peristaltic pump that moves fluid from patented Flo-thru cells, and a computer that regulates the fluid flow onto the blade. As the blade cuts through a plant stem, herbicide is deposited on the stem.

The Brush Monitor separates the operations of mowing and applying herbicides into two specialized chambers (Figure 25). The first chamber has cutting blades capable of handling 2-3 inch diameter stems. The cut debris is blown to the side of the mower. The remaining cut stubble is treated with herbicide in the second chamber. In the enclosed herbicide chamber, the stubble encounters two treatment phases. First, a row of nozzles sprays herbicides directly onto the stubble. Then, the system catches any unabsorbed herbicides in a series of scrapers, brushes and chains, which wipe product onto the stubble in the second application stage.

Pelletized formulations vary in size with the product used. Smaller pellets can be applied with the same equipment used for applying granular formulations. The most common advantage of pellets is they can be spread by hand, with appropriate applicator protection. Backpack blowers have also been adapted to spread pelleted products. Pellets are a convenient method for treating inaccessible areas or small weed infestations. Several herbicide suppliers have developed hand applicators for use with their specific products.

Granular spreaders, which may be motorized or manually operated, are used to apply granular and pelletized formulations (Figure 26). They are of particular value in reaching areas not readily accessible to spray equipment. Granular applicators commonly used for rights-of-way sites distribute granular herbicides by spinning or whirling discs. The application is usually a broadcast treatment with even distribution over the entire area. Granular spreaders are typically inexpensive, simple in design, have minimal drift hazard, and afford less exposure hazard to the applicator. Granule formulations are typically more expensive per acre than liquid formulations and cannot be used for foliage applications because granules will not adhere to most foliage. Granule spreaders need to be calibrated for each product formulation, because formulations differ in particle size and bulk density, as well as for each operator. Some granular applicators are ground driven and it is important to maintain uniform speed so that application rates and swath width are not changed. Traveling too fast for ground conditions can cause bouncing of the equipment and uneven application. The spinning disc types may give poor lateral distribution, especially on side slopes. A granular applicator should be easy to clean and fill and have mechanical agitation over the outlet holes. This prevents clogging and helps keep the flow rate constant.

There is an array of equipment available for applying herbicides. Each is designed for specific application situations. It is the responsibility of each applicator to use equipment correctly. The applicator controls the quality of the results.