Controlling Phytophthora Root Rot

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Controlled Dispensing Of Liquids Avoids Spills and Improves Profits And Productivity At Rancho Rodoro Avocado and Lemon Tree Farm

 When the owner of Rancho Rodero, a 40 acre avocado and lemon tree farm in the Santa Clara River Valley of California,  decided to utilize their existing irrigation system to apply controlled quantities of phosphorous acid to minimize phyotophthora root rot spread, he ran into a serious application problem:  how to find a reliable pump that could safely transfer controlled quantities of the  acid to the fertilizer tanks, and do it without spills, leaks, or loss of costly chemical inventory.

Previously, he had  successfully used tree trunk injection of the  phosphorous acid just prior to the initiation of new root growth in April, July  and September. Using this standard, acceptable method he had recovered 6 acres of moderately to severely diseased trees, and was now operating a thriving avocado grove. This method proved appropriate for this severe problem, but owner Randy Axell felt it was overkill for control and disinfection of the slightly diseased areas of the orchard. That’s why he opted to utilize their existing irrigation system to economically apply the phosphite.  Using the irrigation system is a cost effective method because it delivers the phosphite to the trees at the problem area as part of the regular irrigation  program and avoids additional excessive water use.  Although the idea made a lot of sense, putting it into action presented problems he didn’t expect.

Here’s why. The chemicals,  PhosgrowTM , a registered California fertilizer,  were supplied in 55-gallon drums which he stored in vertical position. But the application of these liquids via the irrigation system  made it necessary to find a suitable pump to safely transfer  controlled amounts of these chemicals into his fertilizer tanks, and to do without spills. The operation involved transferring the concentrated phosphite to a 2 ½ gallon container … and it had to accomplish this quickly and safely in complete compliance with local environmental regulations.

The pump had to be constructed so that all fluid contact components would be able to resist being corroded by the acidic chemicals. The design had to assure transfer of the chemicals from the vertical drum so that no manpower or special lift equipment would be necessary to tilt the drum in order to completely empty it so that costly liquid inventory wouldn’t be wasted. Axell found it in the design and construction of the all-plastic polypropylene GoatThroat pumps…a unique, low cost, zero-to-low maintenance pump widely used by the chemical, pharmaceutical, food and other process industries.

According to Randall Axell, “This simple, rugged pump design comes with adapters to fit all my different containers.   We simply open the tap and dispense the exact amount we need. No spills and no wasted liquid inventory. This tool improved the safety of our workers and helped us be more compliant with local regulations.  Because we have control over the amount of phosphite which is dispenses at one time, we are able to meet our HASSP requirements more easily.  I am able to focus on improving crop production instead of managing chemicals spills.  And, with proper PPR management,  our crop production is up 20% since 2004”.