With supply of fertiliser inputs from overseas becoming increasingly expensive and erratic, it’s worth focusing on our own resources.
Magnesium is an essential input on virtually all intensive dairy farms and there is no guarantee that magnesium oxide products, all of which are overseas sourced, will continue to be available when required.
Golden Bay dolomite is a local deposit, supply is guaranteed, and prices, unlike other magnesium products, reflect only the cost of production and supply.
There is only one source of dolomite in New Zealand and it’s located in Golden Bay, hence the name.
The price of Golden Bay dolomite delivered varies depending on where you farm. The price delivered to Canterbury Plains farmers is considerably less than for farmers in Taranaki.
Regardless of where in New Zealand you’re situated, if magnesium is required dolomite provides outstanding value regardless of price.
Dolomite is often referred to as dolomite lime and herein lies much of the confusion that surrounds it.
In pastoral situations, based on extensive experience over the last 23 years, dolomite is best applied at the rate at which magnesium is required.
High rates, based on soil test calculations alone do not provide better protection against calcium/magnesium metabolic disorders in spring.
In our experience 200 – 250kg/ha applied annually is sufficient to ensure that the likelihood of finding cows down behind hedges at 5.00 in the morning is largely eliminated.
Clients report the occasional wobbly cow, usually during prolonged periods of wet cold weather, however unless there is another contributing factor, there’s time to treat and the response is rapid.
Valuable time is not lost deferring immediate tasks to treat cows that may not get to their feet immediately, and cows down for even a few hours suffer significant muscle damage.
High producing animals in spring are typically on a metabolic knife edge and any shortage or imbalance of nutrient reduces production for the current season.
Magnesium deficiencies are seldom just that. Calcium is nearly always involved, and this is where dolomite is unique.
It contains 24% calcium and 11.5% magnesium, in what has proved to be the near perfect ratio for both plants and animals.
That’s somewhat unsurprising as dolomite is an ancient seabed deposit, laid down over millions of years, and its application finely ground is largely a recycling process returning it to the land from where it originated.
A point made in a Radio NZ interview years ago was that although slivers of Mt Burnett are being mined it’s done so in an environmentally responsible way with ongoing native plant re-establishment as part of the process.
In our view any loss is far outweighed by the benefits available to pastoral farmers from a low-rate yearly application.
Farmers can easily calculate the financial benefits from an annual investment, often less than $50.00/ha, with the loss of one top producing cow and her milksolids for the season exceeding $5,000.00.
Dolomite may be applied at any time with a range of other benefits and still provide protection in spring.
Dolomite is a recognised soil conditioner with lighter sandy and pumice-based soils of the North Island benefiting from a little extra stickiness that speeds the formation of soil crumb.
On heavier soils that are prone to treading damage during wet periods over winter it helps speed physical re-structing allowing more rapid recovery of pasture during spring and summer.
Being a natural seabed deposit, it contains a wide range of beneficial trace elements, and although they exist in parts per million and therefore hard to accurately value, there are many people world-wide that swallow a capsule a day knowing that they are better off as a result.
For more information call Peter on 0800 436 566.