A common misconception is that any fertiliser product that provides a noticeable response soon after application will need to be reapplied frequently to gain a long-term affect.
Golden Bay Dolomite often provides both an almost immediate response and a season long affect.
When it comes to a magnesium/calcium fertiliser GB Dolomite is almost the perfect fit. Although technically a marble therefore extremely hard, when ground to the typical particle size of product supplied for pasture the response can be very rapid.
The initial breakdown of very fine particles takes place mostly as a result of the acidic conditions on the soil surface, releasing both magnesium and calcium. Larger particles incorporated into the soil as result of treading and earthworm activity will breakdown more slowly providing a steady supply over twelve months.
Dolomite encourages earthworm activity. The most common earthworm is the Apporectodea caliginosa. Beneficial earthworms in pasture are almost universally introduced worms that arrived in the ballast of ships or with trees that began arriving here over one hundred years ago with native bush dwelling earthworms not suited to pastoral conditions.
Dolomite itself has a soil conditioning or flocculating effect. Flocculation is the process of soil particles joining together in clumps thereby increasing pore space. Increased pore space speeds moisture movement through the soil.
In conjunction with strong earthworm activity moisture infiltration rates increase. One study showed the infiltration rate increasing from 12.5 mm to 25 mm/hr as result of increased earthworm numbers and activity. The same study also showed moisture holding capacity increased 17%.
This means earlier spring growth as a result of better drainage in winter as well as higher pasture production over summer.
With improved physical soil structures nutrient is cycled more rapidly resulting in more total growth throughout the season. Only a very small percentage of nutrients stored in the soil are available to plants at any given time so speed of cycling is important.
With greater nutrient availability pasture energy levels can also be expected to be higher, resulting in better animal gut function with the resultant dung more readily incorporated back into the soil.
Dolomite does not replace required inputs of phosphorus and sulphur but does help address the ongoing requirements of both magnesium and calcium.
Ideally Base Saturation Calcium levels should be close to 65% with a marked increase in phosphorus availability between pH 6.0 and 6.5. Magnesium Base Saturation levels of 10% ensures maximum pasture growth.
At this level there is also likely to be sufficient plant available magnesium for only small quantities of extra magnesium required to be fed at strategic times and dolomite either drenched, dusted, or incorporated into a lick, is effective.