The New Zealand Sports Turf Institute says playing fields, bowling greens and golf courses rely on use of endosulfan and it does not want the insecticide prohibited.
The Environmental Risk Management Authority is reassessing the insecticide and deciding whether to allow its continued usage.
Endosulfan is currently used on some vegetables and berries as well as to control earthworms.
At a public hearing on Tuesday, the Sports Institute said playing fields worth $200,000, could be ruined in two to three years if earthworms cannot be controlled by endosulfan.
The institute wants the insecticide to be permitted in New Zealand with restrictions defining the way it is applied.
ERMA said the hearing should finish on Wednesday. A decision is expected within 30 days.