Irrigation NZ Training Course at the MicroFarm
We were delighted to host Vicky Bloomer from Drop Consulting to present the Irrigation New Zealand Performance Assessor training course at the Centre for Land and Water this week. And what a wet week it was, so we thank them for breaking the drought in this part of the country.
The course participants were out and about visiting Drumpeel Farms to assess a centre pivot, our neighbours YummyFruit to assess drip/micro system and an Oderings nursery to look at a solid set system. At the LandWISE MicroFarm, they assessed the linear move irrigator. LandWISE Project manager Olivia Webster is one of the course participants
The performance assessment course is based on the Irrigation New Zealand Piped Irrigation System Performance Assessment Code of Practice, initially developed by Dan Bloomer at Page Bloomer Associates. The concept of irrigation performance assessment was strongly promoted by Hugh Ritchie following his Nuffield scholar experiences in the USA and he was a key player in obtaining funding support to write the New Zealand codes in the first place.
The MicroFarm Linear
The LandWISE linear machine was donated by Hugh and Sharon Ritchie. It was converted to a low energy precision application system (LEPA) by WaterForce who have been excellent with anything water related we need. The machine began life as a 460m multi-span linear at Drumpeel, and when it was due for replacement, Hugh collected the best bits and rebuilt it to fit the LandWISE MicroFarm. In its early days, it was repeatedly measured as a test case while the Code of Practice was developed! It was also used in other SFF projects assessing impacts of application intensity of soil surface redistribution and consequent soil moisture uniformity.
Quinn Elstone at WaterForce deigned the LEPA system specifically for the MicroFarm layout, centring the outlets above each 2m bed. We run two parallel header pipes along the linear span, and we can split the sprinklers between them. We can use the sprinklers as rotators doing a wide overlapping ~12m spread to maximise uniformity and minimise application intensity. Or we can run them as sprays with a 5m spread, keeping application tighter to our 12m plots. A third option is changing the nozzles to tighter 2m splash plates that water each bed individually. Or we can turn individual nozzles off.
Images of irrigator showing 12m spread rotators on left, 2m splash plates in centre and 5m sprays at right
Why LEPA?
It gives us tremendous flexibility.
In the LEPA system the nozzles are very close to the ground, so we see very little effect in windier conditions. And because we generally run the irrigation during the day to take advantage of our solar electricity system for pumping, there is often a bit more breeze than at night. We haven’t converted the machine from diesel yet – that is on a long list!
We can tailor irrigation to treatments.
In our Carbon Positive trial, we’re running 6 beds per treatment plot, and sometimes we want to do different things to different treatments. When the nozzles are running as sprays, there is very little overpal of treatments.
The WaterForce LEPA system lets us turn one treatment plot off and irrigate the other two, or irrigate only one plot. We can run nutrient solution in one header and fresh water in the other and fertigate some plots and not others, even though we have three different treatments under the irrigator at any time. For us, the Drumpeel/WaterForce machine has been life changing because without flexible high-quality irrigation, our trial work is severely impacted.
We are tremendously grateful to the Ritchies for the generous donation, and to WaterForce for their supply and installation of the components. It is this kind of community support that characterises LandWISE and has allowed it to be a success.