A GROWER society dedicated to uncovering the issues behind soil and land degradation held its 40th annual general meeting in Perth last week.
While membership of the Whittington Interceptor Sustainable Agriculture Land Treatment Society (WISALTS) has dropped from 120 down to 40, the group remains steadfast to capture and retain water "where it falls", according to returning president Jim Sorgiovanni.
Other elected members included senior vice president Phillip Surtees, junior vice president Hugh "Jock" Rogers, Sue Pike as interim secretary and Neville Marsh as treasurer.
Mr Sorgiovanni said the WISALTS system, established and put into practice in WA by Brookton farmer Henry "Harry" Whittington OAM, is as applicable today as it was then.
"Harry Whittington was the start of it here but the system has been around for five to 6000 years," Mr Sorgiovanni said.
He said Mr Whittington started exploring contour banks in the late 1940s as a way of treating salt-affected land on his farm.
Despite an "abundant" water supply after WWII, the once productive farm was becoming affected by salt and water availability decreased.
Mr Sorgiovanni said the "system" was about developing barriers in the soil to reduce movement.
"Once water starts to move it multiplies itself eight times every kilometre, whether it is on the surface or subsurface," he said.
"The surface water will just create erosion and disappears and either goes into a lake or a pond or river and gone and there's your production gone.
"But the subsurface water movement does the most damage and as when it starts moving it creates a vacuum and takes all the water soluble nutrients along with it."
He said interceptor banks helped resolve this as well as salt-affected land.
"We're not scientists, we're practical people - it is about finding these natural barriers and going down to the sea horizon and pushing the first lot of topsoil out of the way and getting into the sea horizon and using that clay as a seal to stop water movement," he said.
A key part of the group's function now is preserving the works of Mr Whittington, who passed away in 1999.
In 2013, the group gifted its papers to Murdoch University to create the Harry Whittington Collection, which includes more than 900 farm plans, reports and photographs, totalling more than 6400 catalogued items.
Later this year the group will mark its 40th anniversary with a visit to Aldersyde Farm, where the WISALTS system is used extensively.
