A key part of New Zealand's biosecurity relies on domestic pathway management - slowing down or restricting the spread of pests to other parts of the country. When moving from one place to another, a number of "hitch-hikers" can come along for the ride, on cars, machinery, sports equipment or even clothes.
To find measures to decrease pests being transported on large machinery, the National Pest Control Association (NPCA) has established the "Machine Hygiene Forum".
This group involves regional council biosecurity managers, the Ministry for Primary Industry, rural contractors and Federated Farmers targeting rural contractors and large machine operators moving from region to region.
A recent study showed a contaminated machine is likely to have at least one hitch-hiker pest on board at any given time. Soil on one bulldozer in Canterbury contained seeds from 73 different weed species.
Prevention is the best medicine. Simple hygiene steps, such as removing visible soil or plant material before sending machines to new locations, go a long way to solving the problem.
The didymo project is a prime example. The simple message of "check, clean, dry" successfully raised the profile of didymo and minimised spread.
Federated Farmers has emphasised the importance of keeping any rules voluntary, with the industry self-managing implementation. The intention is to initially test the model in one industry, then extend to others.