Threat to crops

Waikato farmers will need to ramp up their biosecurity practices if they are to stop velvetleaf spreading throughout the region this summer.

The warning from local and central government comes nearly four months on since the invasive weed was discovered in a fodderbeet crop and then later in maize crops around the region.

If left unchecked, farmers risked facing a substantial problem in containing the plant over the long term, the Ministry for Primary Industries’ Catherine Duthie said at a recent velvetleaf information meeting at Elstow near Te Aroha.

A single, well grown plant produced as much as 17,000 seeds in pods that were easily spread if broken.

‘‘It’s estimated that unmanaged, it can reduce the yields of arable crops by 30-40 per cent,’’ she said.

The Waikato Regional Council inspected 101 Waikato farms since it was discovered in late April this year and found the plant on 29 farms throughout the region, mostly in the Te Aroha-Waihou area.

There are another 70 at-risk farms that the council will be following up in spring.

The response in Waikato was different to other regions because of its discovery in maize crops, Waikato Regional Council pest plants team leader Darion Embling said.