Site investigation of Cyperus rotundus

Proposed sand mining site

Project: An investigation into the presence of Cyperus rotundus on a proposed sand mining site

Client: Perry Aggregates

Timeframe: 2011

In 2011 SSDM was engaged by Perry Aggregates to carry out a site investigation of a proposed sand mining site in Tuakau, Auckland.

The scope of this investigation was to carry out a vegetation survey that would identify and record the extent of any potential contamination by Cyperus rotundus  (nut sedge) and any other problematic species  within  and around the proposed site for sand stockpiling.

Nut sedge is commonly found on farmland and waste areas and is officially designated as a pest by the Environment Waikato Regional Council. In recent years there have been instances of sand carpet sports fields being contaminated with nut sedge seed and its subsequent establishment has had a negative effect on the grow-in process of numerous sports fields.

SSDM was engaged to:

  • Assess the extent of existing populations of Cyperus rotundus
  • Assess the likelihood of future contamination of the sand mine from  Cyperus rotundus
  • Recommend control measures to minimise the risk of any seed contamination that may occur from wind borne seed migration.

A comprehensive report was produced for the client, with the site investigaton recording no presence of Cyperus rotundus. The report also  included a plant species list and recommendations for future management was provided to the client. A range of chemical and cultural methods of minimising the risk of future contamination were provided with a recommendation that regular  monitoring should continue in order to establish a suitable vegetation management strategy for the site and surrounding farmland.

nut sedge invasion during couch grow-in