Bill Gordon: ""The decision to invest in height control for your boom sprayer largely depends on the width of the boom and the type of terrain you're working on.

In relatively flat country, the benefits may not be as significant. However, in areas with undulating terrain, height control systems can be invaluable for maintaining a consistent height above the target. This is critical for ensuring proper spray overlap and achieving effective canopy penetration with your droplets.

Height control systems come with different types of sensors, and their placement on the boom is crucial. Most setups include at least one sensor in the centre section and one on each side of the main boom. Some systems also feature sensors on the breakaway sections, allowing them to lift independently to maintain the correct height.

The height between the nozzle and the ground should be carefully monitored to ensure optimal performance. It's important to place the sensors in a position where they won't be affected by certain nozzle types, as interference can cause the system to misread and react unpredictably.

Height control systems can make a noticeable difference in maintaining boom stability and improving spray efficiency, particularly in challenging canopies. Ensuring they are correctly installed and calibrated is key to maximising their effectiveness.

Graham Betts: Another example of a boom center, this is what we call the inverted trapese. On other brands of sprayers the actual trapese strap goes that way. It helps with the suspension of the boom, disconnected from the tyre.

Graham Betts: I just want to show you an example here of a pendulum boom. John Deer choose to have a pendulum boom. So they carry the whole boom on this center point here, and the other thing John Deere have chosen to do is bring this point down as low as possible to the nozzle. That reduces the possibility of the boom going sideways if the sprayer moves. The positive of that is, if the tyres go down a hole or a bit of a bump or whatever, it has less impact on the booms wings. The negative to this is we've got to have a system that firms up the center section if the automatic boom height raises a boom or you manually raise it. Otherwise it's a very positive system to have a pendulum boom.

Graham Betts: The Hardi boom spray has what we call a pendulum trapeze boom, which is quite unique. It has a pendulum point in there, then you go to two pivot points there and the trapese on that part there. That's very unique so it gives a lot of flexibility, but it really depends on the spring system also. At the moment the coil spring is wound up too tight so if the wheel went down a hole, that would transfer that drop out onto the end of the boom. To screw them in like that you'd need to be on very level ground. When you're not on level ground these bolts need to be adjusted out to relax the spring. The coil spring there is just to return the boom back to level.

Graham Betts: What I want to show you on this boom spray spray is what we call a rigid or fixed boom centre. It has no pendelum or trapese. So this point here, has got a bar across the top down to there and there's no pivot point in here. So it's a rigid boom section. Where others will have what we call a pendelum, there'll be a pivot point there. Other manufacturers have a strap down here, what we call a trapese boom. The reason this is important is we want to isolate the impact of the tyre on the boom. So when you have a rigid section like that you've gotta have a very good tyre system and suspension system to stop having an impact on the boom wing.

Bill Gordon: This standard boom doesn't have any high control system fitted, we're relying on the stability of the boom to actually stop it from striking the ground. The one thing that can be fitted to a machine is something like a jockey wheel here that will stop the travel and reduce the boom strikes, the other thing this has fitted is a rail on the outside as well, this is probably an original feature, this is something the grower has actually added. So this is a complete manual system to stop boom strikes, pretty cheap and pretty effective. This can be coupled with something like a hydraulic load sensor in the ram, so that when the boom goes down and the wheel takes the weight can actually reverse the flow in the hydraulic sensor and just lift the boom gently, so this is a bare minimum cheap cost. The next step might be something like load sensors on hydraulic rams which work well on booms that have some sort of cable tie or something that will stop them going back when the wheel strikes, or the next step after that is something like an ultrasonic sensor out from the boom that detects the height as you're going along.