Protecting crops from insect attack – are neonicotinoids worth it?

By Mark Ross

Growers of arable crops, forage brassicas and pasture grasses would suffer financial losses if vital insecticides were taken from the market.

A report investigating the value of neonicotinoid seed treatments to New Zealand’s economy, by BERL Economics, estimates their contribution as up to $1.2 billion.

Neonicotinoids (neonics) help protect crops and pasture against attack from insects like Argentine stem Weevils, black beetles, grass grub, aphids and more. Most are applied as a seed coating — protecting the plant as it grows.

They are used for cereals, forage brassicas, grass seed, maize/sweetcorn, potatoes and winter squash/pumpkins as well as flea control for cats and dogs and pour-on treatment for flies and lice in sheep.

The ‘Economic value of neonicotinoid seed treatment to New Zealand’ report estimates that 62 percent of the arable grain, forage brassica and pasture grass seeds are planted with neonic treated seeds. It estimates that the cost to the economy of removing these seed treatments as between $800 million and $1.2 billion in the short to medium term.

The cost takes into account suppliers, producers and increased expenditure from those working directly or indirectly in the industry.

Commissioned by Agcarm in 2014, the report remains relevant today. In fact, the cost would be even higher if inflation, increased costs for resourcing, health and safety, and fuel hikes were taken into account. A lack of alternative options will also increase the cost.

The main alternatives available to New Zealand growers include organophosphates, carbamates and synthetic pyrethroids. These alternatives are often more toxic. Organophosphates are one of the most effective (yet toxic) alternatives to neonic seed treatment, but their use is reducing. The Environmental Protection Authority made the decision to cease approving many organophosphates in a staged approach from 2016.

Aside from the economic ramifications, the report assesses the employment generated as a result of these seed treatments. This equates to approximately 5,300 full time employees.

Crop yields would also fall by a third if alternate crop protection tools were used instead of these seed treatments. The value of the treated seeds versus non-treated seeds alone is worth $368 million.

One of the unique benefits of using neonic seed treatments is that the active ingredient can be applied at very low rates per hectare, reducing the number of insecticide applications in comparison to spray treatments.

Seed treatment with neonicotinoid application is highly targeted and one of the most environmentally-friendly means of crop protection product application. Other benefits include low toxicity to humans and other mammals and no reported effect on bee health since first being registered in New Zealand in the early 1990s.

The relationship between neonic seed treatments and New Zealand’s bee population has sparked much debate in recent years. Links to bee health were touched upon in the report, with the following observations from industry:

  • Seed treatments represent a very low risk to bees.
  • No unexplained bee colony losses were linked with proper use of neonic seed treatments in New Zealand.
  • Correct stewardship mitigates the risk of neonic dust exposure to bees.

Unlike Europe, there is very limited use of neonics, if any, as a foliar spray, so dispersal into the environment does not occur. Locally grown crops that use neonics are generally non-attractive to bees and are pollinated by wind or other insects.

So as the report concludes, these seed treatments aid New Zealand’s economy and its farmers. It underscores that neonics are a vital tool for farmers in growing safe, healthy and sustainable food for an escalating global population.