IRRI, PhilRice, The Rotavator & Lorenzo’s Secret

“The New Thinking For Agriculture” espoused by Secretary of Agriculture William Dar/Manong Willie has yet to consider what the rotavator can do to enrich the farmers’ pockets by first enriching their soils!

I have a 55-year direct experience with the Howard rotavator in my hometown Asingan in eastern Pangasinan. That 1965, I was instructing the driver of the big tractor not to set the blades to any depth but just drive through the field, and because the Howard rotavator was heavy, it cut into the soil anyway, about 2-3 inches, which is what I wanted. My brother-in-law Lorenzo Casasus, was there at that time; in later years he copied the shallow cultivation with his Kuliglig hand tractor and rototiller. The results? His neighbors could not match his yields even if they tried to copy all his methods – he did not tell them about the magic that his rototiller was doing.

What was Lorenzo’s Secret? Because the rotary blades had their tines set against each other, they cut the ground and weeds finely and mixed them in the same rotating motion. When that big Howard rotavator was finished, it actually had created & distributed a mulch of soil & weeds throughout the field. As fine an organic fertilizer as you could get – cheaper too!

I got the idea of what I now call Lorenzo’s Secret from the books of Edward H Faulkner, Plowman’s Folly (published 1943) and Soil Development (1952), the books I discovered in the open shelves of the UP College of Agriculture library when I was already an instructor mid-1960. Mr Faulkner called what he did trash farming.

Has either PhilRice or IRRI discovered Lorenzo’s Secret? None of the webpages of IRRI[1] give a hint. The above image shows a rotavator being used – but not as a mulch maker as I have described.

In May 2018, PhilRice had this report: “PhilRice Develops Cost-Effective Farm Machines With Multiple Applications[2].” This is the PhilRice rototiller, which is “a multi-purpose machine that can be used as a rotavator, transplanter, seeder, and a multi-seeder…”

Now, IRRI describes the rototiller for rice primary tillage, which is land preparation. The IRRI Rice Knowledge Bank says:

Primary tillage is the first soil tillage after the last harvest. It is normally conducted when the soil is wet enough to allow plowing and strong enough to give reasonable levels of traction.

Unfortunately, as the above image shows, the rototiller is used as if it were the ordinary hand tractor cultivator – digging deep into the soil to bring out the clods of soil and later to level them. Too late the hero!

How come I have not come across studies by PhilRice and IRRI about the rotavator?

The IRRI webpage says one of the objectives of primary tillage is to “kill weeds by burying or cutting and exposing the roots.” If you use the rotavator properly, it will kill weeds by cutting them to pieces, mixing them with the soil, creating a rich topsoil.

That is what PhilRice and IRRI have not discovered yet – Lorenzo’s Secret!@517

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[1] http://www.knowledgebank.irri.org/images/docs/landpreparation-irri-farm-machinery.pdf

[2] https://www.philrice.gov.ph/philrice-develops-cost-effective-farm-machines-multiple-applications/