''They didn't get a chance to seed.''
All properties which had been contaminated with velvetleaf had been working to develop individual farm management plans to continue the battle with the pest.
''The risk isn't over because of what you did. (Seed) can remain dormant in the ground for 60 years.''
On the positive side, the farmers whose properties had been infected were working hard to keep the pest at bay, Mr Milne said.
''They want to stop it establishing on their own properties and in the region.''
While there had been no confirmed cases in Southland this year, in Otago one farmer in the Teviot Valley had found a 1m-tall plant in one of his crops.
It was a timely reminder to remain vigilant and keep an eye on fodder beet crops, Mr Milne said.
Velvetleaf could germinate at any stage and, after the summer Southland had had, there was a chance the pest could germinate later in the season than last year, he said.
''It's really encouraging we haven't had any plants found. People are looking out there. We have got support from the farming community and I'm hopeful that we still have the opportunity to prevent it establishing.''
If farmers notice the invasive weed, they should contact MPI on 0800 809-966.