“However, both are coming under pressure overseas, metaldehyde from contamination of surface and drinking water supplies, and methiocarb from secondary poisoning of birds,” says Peter Westaway, CEO of Orion AgriScience.
 

Iron chelate is a third generation active ingredient for slug baits, with unique advantages over metaldehyde and methiocarb.
 

It is non-toxic to all mammals, including dogs and cats. Iron chelate is approved for use as a dietary supplement. It is toxic only to molluscs, which use an oxygen transfer system based on copper instead of iron, Westaway says.
 

Iron chelate interrupts this oxygen carrier system when it is ingested by the slug, causing death.
 

The mode of action of iron chelate does not involve the excessive secretion of mucous and dehydration as it does with metaldehyde, which can result in recovery in wetter conditions, he says.
 

Being uniquely toxic to molluscs also has other advantages, Westaway adds.
 

“It is non-toxic to slug predators such as carabid beetles and spiders. Conserving these slug predators is doubly important as not only do they prey on slugs, but also predate on other pests such as insects.”
 

Westaway is an enthusiastic proponent of the need to move agriculture and horticulture away from the older chemistry.
 

“While iron chelate slug baits have been on the market for several years, these have been extruded granules.
 

“Orion has been working with an innovative R & D company to develop a core based pellet, where the iron chelate is built up around a small mineral chip in the centre of the pellet.”
 

The result of this innovation is Dusk, a small, consistently sized and evenly weighted pellet. “It flows easily when drilling, and spreads evenly if being applied by spinner. Being a small pellet, with approximately 120 baits per gram, results in a high number of baiting points for better coverage.”
 

Dusk nominally contains 54 gram per kilogram (5.4 per cent) of iron chelate.
 

However, because the iron chelate is contained in a coating around a chip, the actual concentration in the edible coating is much higher.
 

The coating is also formulated with a blend of cereal based phagostimulants to encourage feeding. “This elevated iron chelate concentration, together with feeding attractants which slugs find highly palatable, means that the pellet is able to deliver a lethal dose in a single feed,” Westaway says.
 

The core based formulation is also designed to be weather resistant, and so maintain its integrity and palatability under wet conditions until eaten.
 

For more detail visit www.orionagriscience. co.nz or phone 0800 674 6627.