Wet Blade (WB) Technology directs chemical to the cut portion of the leaf surface during mowing. This dual action of mowing and applying product eliminates the need for separate chemical application. Applying chemical to the cut portion of the leaf allows the product to move directly into the plant via xylem and phloem tissue. This action also limits the likelihood of herbicide movement from spray drift. Four field trials were conducted in 2004 in Blacksburg, VA to evaluate WB for herbicide, fertilizer, and plant growth regulator (PGR) application in comparison to traditional application methods. Smooth crabgrass (Digitaria ischaemum) control was evaluated with WB and foliar spray with single applications of quinclorac at 0.75 and 1.5 lbs ai/A, fenoxaprop at 0.06 and 0.11 lbs ai/A, MSMA at 2 lbs ai/A, and mesotrione at 0.5 lbs ai/A. White clover (Trifolium repens), dandelion (Taraxacum officinale), and broadleaf plantain (Plantago major) control was evaluated with WB and foliar spray with single applications of quinclorac at 0.38 and 0.75 lbs ai/A, a premixture of 2,4-D, dicamba, and mecoprop-p at 2.38, 0.22, and 0.63 lbs ai/A, respectively, and a premixture of 2,4-D, clopyralid, and dicamba at 2.25, 0.28, and 0.28 lbs ai/A, respectively, and a premixture of clopyralid and triclopyr at 0.09 and 0.28 lbs ai/A, respectively. Tall fescue (Festuca arundinacea) color, quality, and clipping weight was evaluated with several turfgrass fertilizers and biostimulants applied weekly at 0.25 lbs N/1000 sq. ft, including liquid urea 33-0-0, Ferromec 15-0-0, Peters 20-20-20, 28-0-0 slow release formulation, TurfVigor 9-3-6, and 46-0-0 granular application applied biweekly at 0.5 lbs N/1000 sq. ft. for comparison. Tall fescue color, quality, and clipping weight was evaluated with trinexapac-ethyl at 0.38 lbs ai/A, ethephon at 3.4 lbs ai/A, and mefluidide at 0.13 lbs ai/A, all of these treatments were applied with and without a turfgrass biostimulant (Ferromec) which contains a 15-0-0 nutrient analysis, sulphur, and iron.
Herbicides in the smooth crabgrass trial did not injury or reduce color of turfgrass. A test site with heavy infestation of smooth crabgrass was chosen and herbicides did not control crabgrass greater than 50 percent. Spray applications did not differ from WB application for smooth crabgrass and white clover control. All treatments controlled clover between 85 and 60 percent. Both application methods failed to control broadleaf plantain and dandelion regardless of herbicide and data for these two species were highly variable between plots. The pre-mixture of 2,4-D, mecoprop-p, and dicamba controlled broadleaf plantain 50 percent when applied as foliar spray and 25 percent when WB was used and constituted the only statistical difference between application method in the study. WB fertilizer applications did not affect turf color, quality, injury, and clipping weight. WB PGR treatments were not significantly different from foliar spray treatments for clipping weight. Trinexapac-ethyl, ethephon, and mefluidide reduced clipping weight compared to the nontreated. Mefluidide significantly injured turf at 25 percent when applied with WB and 85 percent when foliar applied.
WB herbicide applications were not statistically different from foliar spray application, however trends indicate only a slight reduction in control when using WB technology. Weed control with WB technology is a practical option, and holds potential for use in turfgrass. Similar trends were observed for PGR applications in that WB applications numeric trends tended to favour foliar spray over WB for turf growth regulation. Mefluidide applications with WB had significantly less injury than foliar spray applications. Even though this injury is unacceptable, this evidence indicates that mefluidide is more effectively delivered by foliar spray applications than WB, which could be true with other products not evaluated. Although WB applications might occasionally be less effective that an equivalent foliar spray, the ease of operation associated with WB outweighs the potential minor reduction in efficacy. The lack of statistical differences between WB and foliar spray techniques proves that WB can control white clover and smooth crabgrass and regulate turfgrass equivalent to conventional foliar spray technology.