Velvetleaf has been spotted in fodder crops across New Zealand this year, and a campaign is under way to stop it spreading. The incursion is thought to have originated from contaminated fodder beet seeds.

PIANZ said some parties have attempted to put the blame for its appearance on farms on use of chicken litter or any fertiliser sourcing from meat chicken or layer hen farms.

The argument being used is that viable weed seeds from imported grains which allegedly contain velvet leaf survive the milling process, and then are spread when the litter or fertiliser using layer faeces is spread on properties, particularly arable farms.

However, PIANZ said that the feed mills are required to use grinding or a heat-treatment process to prevent any viable seeds remaining in the litter, and they are also required to test whether viable seeds survive and have results available for inspection by the Ministry for Primary Industries.

PIANZ added that all feed companies that are members of the NZFMA (New Zealand Feed Manufacturers Association – comprising all companies who supply feed for meat chicken companies, who then supply chicken litter and layer hens) have not had positive results for viable seeds after the conditioning process.