[farmeromus]

I have been getting different info on fungicide tip application. Is the twin spray tips necessary for good coverage for fungicide application.

 

[mbfarmer]

Well with one 10 gallon tip you will be getting way too many large drops. Large
Drops means very poor coverage. With a twin tip, say two 5 gallons nozzles you will have much better droplet size. Probably twice as good of coverage with the same gallons per acre. That doesn't matter if you have aim or not.

 

[Spraysmart]

I would agree with MBfarmer in principle. The important thing with nozzles for fungicide, is that a nozzle that is fantastic for fusarium coverage (usually a high angle twin nozzle) isn't usually that good for canopy penetration for fungicide on canola. If your going to go that way I would recommend that you do at least 12.5 to 15 gallons to make sure your getting canopy penetration. AIM or not, there is no substitute for water volume.

 

[southalta]

Would have to agree with mbfarmer. Coverage is most important. This does not mean increased water volume. If your droplets are to large they just roll off the leaf and dont do any good on the ground. Using water sensitive paper we have found better coverage with 6 gallon twins than ten. Also had to increase pressure to 60lbs and the droplets get smaller but far more consistent. Wind becomes more of an issue but coverage is definatly better.

 

[WilgerIndustries]

Right now Tom Wolfe is doing testing on exactly what you ask about. There's definitely a few options as far as twin tips or twin cap adapters (if you are not familiar with the adapters, they essentially let you hook up two tips on one nozzle body).

Tom [and PAMI] are doing testing on the best application for dual-tip spraying, seeing what is the most effective way to spray while maintaining the best coverage. Anticipated to do two [maybe 3] years of testing, in crop and in lab testing. So far they've done one set of in-lab testing, and were pretty surprised by the results in a way. On a whole, switching to a dual-tip does definitely increase coverage, but they found similar results seemed to be achieved when even spraying with one [coarser] nozzle at an angle forwards and going fast.

Again, depends on what fungicide you are spraying (i.e. Head blight vs. Soybean rust, etc.) as it make some difference how you want your penetration/coverage. For example, for headblight, Tom found so far that using a single tip at an angle (can't remember what he preferred for an angle - some reason I want to say 30°ish) and going fast causes the spray at hit its terminal velocity pretty darn close to the target (Headblight), and since the droplets are big and you are going fast, the spray starts travelling a lot more horizontally. With the horizontally moving spray, it will hit the majority of the chem on the front of the head, but something like 30-33% of the chem ended up on the back of the head due to a vortex as the spray went around a head.

BUT, the whole idea means you'd have to rotate your boom ever time you were wanting to spray fungicide, which isn't reasonable for a lot of guys. I think the difference between well-picked dual tip spray and one spray going horizontal is one of the "5% more benefit", which isn't a small gain, but it probably isn't worth the time for some guys. If you have a Wilger setup, there is the dual-tip adapter that you could use with a single tip and cap off the back side of the adapter if you wanted to try it out without buying a whole set of tips.