Sign up for email alerts of new Fluid Journal issues!
Fluid Journal : Fluid Journal 1993-1995
Figure 1. Effect of method and timing of N placement (156 lbs/A) on cor n yield, Iowa State University. 200 190 180 170 160 150 Yield (bu/A) Preplant Postplant PIFA Knife Figure 2. Effectiveness of PIFA in reducing surface runoff losses, Iowa State University. 6 4 2 Nutrient loss (lbs/A) N P PIFA Surface Figure 3. Effect of nitrogen application method on yield of no-till winter wheat in nor thern Montana, Kushnak & Gallagher , Montana State University, 1989 Yield (bu/A) Dryland Irrigated PIFA Knife Broadcast Band PIFA Knifing at preplant; broadcast, band and PIFA at jointing. 70 60 50 40 30 20 Pulse bander The pulse bander applicator developed by Rogers Engineering, Saskatoon, Saskatchewan, has potential to offer subsurface placement (as PIFA) with minimal soil and residue disturbance. This is of particular importance to no-till farmers of the prairies. Unlike the Nutriblast applicator (Arcadian Corporation), which injects a continuous band of fertilizer under pressure (2,000 psi), the pulse bander uses a pulsating high- velocity jet to inject fertilizer at various intervals to a depth of 3 to 4 inches. Flow volume and distances between pulses are regulated electronically and fluid fertilizer is pressurized up to 6,000 psi. Paying dividends Now for a look at the bottom line. Is this concept (PIFA) and the ensuing equipment that has been developed to accomplish point injection producing the desired results? Is it worth the investment? University research suggests that improved yields are afforded by the efficiencies of split timing and PIFA, sometimes even with fertilizer rate reductions. Iowa. Figure 1 shows the results of work during the '80s by Baker et al. of Iowa State University on no-till corn, both preplant and postplant. UAN was injected or knifed at a N rate of 156 lbs/A. Note how PIFA compares even more favorably when applications were made postplant. With PIFA there is none of the root pruning associated with knifing when applications are made postplant. The same series of studies on no-till corn showed how PIFA reduced N leaching, denitrification, and runoff losses when compared with surface applications (Figure 2). Montana. FFF-sponsored work by Kushnak and Gallagher at Montana State University in 1989 showed the effect of N application method on yield of no-till winter wheat under both dry- land and irrigated conditions. Site of the study was in northern Montana. UAN was applied at rates of 60 lbs/A (dryland) and 50 lbs/A (irrigated). Band, knife and PIFA row spacing was ten inches. Application methods were knife, broadcast, band, and PIFA. Note that yield differences between methods of application were not as apparent under dryland conditions (Figure 3). Equipment used for PIFA in both the Iowa and Montana studies was the spoke wheel. Research reports on the use of PIFA technology beyond corn and small grains are somewhat scarce. However, encouraging results have been reported for alfalfa by Havlin et al. at Kansas State University. Blaylock et al. at the University of Wyoming have reported similarly on sugar beets. Many western dealers and growers have reported yield benefits from using the spoke wheel to fertilize grapes, orchards, melons, strawberries, raspberries, tomatoes, potatoes, and shallow-rooted vegetables. The spoke wheel is also being used to fertilize through plastic mulch. Additional field research is needed to expand on the agronomic relevance and benefits associated with PIFA for a variety of western crops. Those crops more suited to PIFA include row crops and others likely to respond to postplanting placement but liable to damage and moisture loss following knife applications. Some interest in PIFA has been expressed by sod growers and amenity turf specialists. Fluids spur technology To a large extent, the physical characteristics of a fertilizer material will determine application efficacy. Despite tremendous advances in dry fertilizer placement and broadcast technology, the simple ability to pump 2 Fluid Journal Winter 1994
Fluid Journal 1996-1998