ACPS (Advanced Citrus Production System

This is the newest method being tested in Florida, to get newly planted citrus trees up and producing fruit before HLB (Citrus Greening) makes the plant non-profitable. A race for a citrus growers profit.

http://www.imok.ufl.edu/docs/pdf/squeezer/042612/schumann.pdf

Millet

This was fascinating, Millet. So sad that FL commercial citrus growers have had to resort to such measures to grow these trees for just 5 years, then do it all over again. But, all these advancements in watering, fertilizing planting rootstock changes will end up creating a hugely productive and effective industry once we can control HLB. What a tremendous amount of work went into this new system.

I found it interesting that in Florida a citrus tree drinks the most between 8 and 9 in the morning. Then the grower applies 6 small doses of water only, between 12;30-PM to 5:30-PM. This is done every two days during the growing season. The best results is grafted on C35- Millet

I'm curious to know what ppmN they are delivering every 2 days and if fertigating in-ground trees in lieu of broadcasting granular fertilizer could encourage the concentration of the roots of an already established tree into a specific area. This would be useful to me if it could be replicated to manageable degree as the quality of my soil (already bad) gets worse (more alkaline) immediatly outside of the particular area that my trees are planted. Potentially, I could acidify certain areas of the root zone by digging 18" by 4" holes and backfilling with a mix of soil, elemental S, & a small amount of iron and then use a version of this fertigation method to encourage my tree's roots to concentrate there where the PH is more appropriate.

I currently fertigate but with numerous emitters distributed inline with and just outside of my tree's dripline. It would not be too much trouble to reconfigure the emitter pattern to distribute food and water locally to a few (maybe 4 per tree) spots beneath the canopy... each corner of an imaginary square...

Certainly there are irrigation timers available that would be up to the task. I'd need to run two zones parallel to one another - one for feeding via continuous injector such as an EZ-FLO (http://www.qcsupply.com/ez-flo-automatic-fertilizer.html), the other for water only. Main water supply (hose spigot) to a splitter to make zone A & zone B. Each zone would have it's own timer immediately after the splitter. Zone A would have the injector behind it...

Think that an established tree could adapt to this method? What ppmN do you think appropriate?

skinn30a,

In another paper they mention using a 100ppm solution of N. With blueberries we use a similar system of growing, but with less technical equipment. The system that is being used with ACPS is a Netafim NMC, and we usually use H. E. Anderson. Since our groundwater from deep wells typically has a pH of ~8.5, we also inject sulfuric acid into the drip to lower the pH of the water. In most cases we try to drop it to 4.5-5.5. This solution is tested with a handheld pH meter at the end of one of the irrigation lines.

Most irrigation timers that are less that $100 will not run two zones simultaneously. One way to accomplish running both lines into one would be to put a splitter at the hose bibb, on each line have a solenoid valve going to the timer. Past the ez-flo, put a check valve and then tie the two lines back together with a tee. The check valve will be necessary in order to keep the pressure from the water only side from pushing water into your fertilizer reservoir. You will also need a vacuum breaker at the hose bibb to prevent back flow of fertilizer solution into the water supply.

http://uploading.com/7faaa434/ACPS-pdf

Excellent information here. Most interesting to me:

Pg. 17: Fertigation ppmN rate used in the ACPS experiment.

Pg. 26: Label for the solution used in the ACPS experiment.

Pg. 34-35: Information about Biochar.

Pg. 39: Correct Admire 4.6F (imidacloprid) application rates. Previously, I have been surprised how hard I had to look to find them. These application rates are for Admire 4.6F (42.8% Imidacloprid; 7 to 14fl oz/acre). Admire 2.0 (21.4% Imidacloprid; 16 to 32 fl oz/acre) is available to us non-commercial folks but I’ve had to hunt for it.

Best,

skinn30a