Roleystone growers Tim and Wilma Byl are among the hundreds of growers across Australia whose businesses are under threat in the face of an impending ban on fenthion.
Third-generation grower Tim Byl claimed if a full ban on the chemical was introduced, it would be "bigger than the cattle crisis".
"This is not just a State issue," Mr Byl said. "There are growers in Queensland and New South Wales who will also be affected."
The Byls are part of the Hills Orchard Improvement Group's Fruit Fly Action Group, initiated last month in response to the Australian Pesticides and Veterinary Medicines Authority's (APVMA) review of the chemical.
The couple grow nectarines, peaches, apricots and plums and the family has been on the orchard for 40 years. They have made every effort to reduce their use of fenthion, but without the chemical their orchard would be destroyed.
"A ban on fenthion would decimate our crops," Mr Byl said. "For the past five years we have used different methods to control fruit fly, including integrated pest management. We use orchard hygiene, trapping and baiting, but none can control a fly in the whole cycle of its life."
The family conducted a trial on alternative fruit fly control methods last season, applying only one application of fenthion compared to the usual two or more.
"That area had 90 per cent loss last summer, even though we still used fenthion we had massive losses," he said. "If they ban it, we might as well shut the gate."
Mr Byl said he would not be happy to use the suggested alternative to fenthion, trichlorfon.
"The industry has spent a colossal amount of money looking for alternatives to fenthion, but hasn't been able to find one," he said. "We've had independent scientists say trichlorfon is 100 times more toxic to the environment than fenthion."
An APVMA spokesman said trichlorfon, a registered fruit fly control product, had the same toxicity as fenthion.