There has been a significant increase in the number of pampas seeds detected on fruit in the 2018 packing season. Any seed attached to fruit is a reject factor and may cause market access issues if found within a shipment or container. Pampas seed “finds” went from 50 in 2016 to 543 in 2018. Almost all seed contaminating fruit was found to have been from the very invasive South American grass-like plant known as pampas (Cortaderia selloana, C. jubata).

Pampas is well-established in most regions where kiwifruit is grown and will be in full-flower in February-May. The seeds (more than 100,000 per flowerhead) will be dispersed by strong winds - any pampas growing in or adjacent to kiwifruit orchards can cause problems. If pampas is growing in your orchard or shelter belt, destroy it now - before it flowers. Plants can be dug out or removed by a digger; mulched by a heavy mulching mower; or sprayed with glyphosate herbicide at 1 part to 100 parts water. Adding an additional amount of surfactant/spreader will assist translocation of the herbicide into the pampas leaves. Follow all precautions to prevent spray drift. Do not attempt to spray pampas in an orchard if fruit has formed on vines. If fruit is present in the orchard, then cut the flower heads from pampas plants and destroy by burning or burial.

Above: Pampas

Below: Toetoe

Pampas is different from the native toetoe in that:

• pampas has an upright growth habit rather than the more prostrate toetoe;
• pampas flowers in late summer-autumn – toetoe flowers in early spring;
• pampas has a different shaped, larger flowerhead: it is upright and cone-shaped rather than the limp-flag flower of the native toetoe;
• pampas generally grows faster than toetoe;
• pampas is very invasive, is a declared pest plant in many regions and is causing problems for kiwifruit;
• toetoe is a native plant and not often found adjacent to orchards. It is not causing any problems to kiwifruit.

KVH is talking to road and rail authorities to request pampas control in the transport corridors.

Email John Mather at KVH if you would like any further information: john.mather@kvh.org.nz