Thrill as you prill with new lime
From the September 2008 edition of Agriculture Today.
Recent availability of a new lime product offers farmers a cost effective alternative to heavy rates, top dressed, at a time when costs of diesel, herbicides, seed and fertiliser have escalated.
At approximately $450 per tonne, the cost of drilling 150 kilograms per hectare of new Calciprill is about one third the cost of broadcasting 2.5 tonnes/ha, according to NSW Department of Primary Industries (DPI) Queanbeyan pasture agronomist, Mike Keys.
"Prilled" lime is a granular product that can be broadcast or distributed through conventional pasture sowing machinery.
Once it becomes wet in the soil, the granules break down to the fine lime particles from which it is made, ensuring normal lime effectiveness.
On the eve of retirement after 40 years with DPI, Mr Keys outlined the effectiveness of the new product to fellow pasture advisory and research staff based on using the product at Braidwood and a recent trial at Sutton.
Prior to a farewell dinner for Mr Keys in Queanbeyan, the group visited two long term acid soils research sites near Canberra.
Both sites were on soils with very low soil pH and high aluminium.
On Robyn and John Ive’s property, "Talaheni", near Murrumbateman they examined the use of low rates of lime and super drilled with the pasture seed.
However, this was before the new product became available.
"Sowing with conventional finely ground lime was extremely difficult to do but once we’d done it, the results were pleasing," Mr Keys said.
At "Talaheni" his research showed that lime at only 150kg/ha drilled with phalaris seed was equally effective in improving the establishment of phalaris seedlings as three t/ha of broadcast lime.
The other location, Ian and Sarah Cusack’s property "Bywong" at Sutton, is now wrapping up a grazing experiment begun in 1998 to examine the effect of various rates of surface applied lime (including no application) and superphosphate on soils, pasture and wool production.
Presenting a summary of that work, project leader Dr Mark Norton said that preliminary results showed benefits to wool production from lime application, although the results tended to be masked by the recent run of drought years.
Mr Keys says results from "Talaheni" and now the use of Calciprill offer a new option for improving phalaris establishment on acid soils.
A final public field day to present the Bywong results will be held at the site on Friday October 17 at 1.00pm.
Contact Mark Norton, Canberra, (02) 6246 5548.
