Cannabis growers beware - you can't escape the long nose of the law.
The unmistakable smell of up to 100 cannabis plants being cultivated at a Hamilton house caught the attention of two passing police constables when it wafted into their car as they drove past on a routine patrol.
Police believe a 57-year-old man living at the house may have been discreetly flushing a ventilation system when the officers went past the Avalon Drive property at 5.45am yesterday.
Under the Misuse of Drugs Act the pair conducted an immediate search of the house they thought the smell was coming from and found between 50 and 100 cannabis plants inside a room.
Shift manager Senior Sergeant Gill Meadows praised the constables for being so alert at the end of a busy night.
"The pair parked their patrol car around the corner and 'followed their nose' to the source of the smell," Ms Meadows said.
"They identified the address where they thought the smell was coming from and knocked on the door. When the door was opened they had little doubt, given the strong smell, that they were at the right place."
They found the plants along with quantities of leaf material and growing and ventilation equipment.
The man appeared in the Hamilton District Court yesterday charged with possession of cannabis and further, more serious charges are likely, Ms Meadows said.
Police spokesman Andrew McAlley said mature marijuana plants were worth around $1000 each, while an ounce of the drug sold for between $350 and $500.
He said if 100 plants were allowed to fully grow, a conservative estimated yield of 225g per plant could fetch up to $400,000 in income.
Ms Meadows said the bust proved the value of preventative patrols.
In the 2011 annual cannabis operation, the national total of plants destroyed was 97,000.
Police usually experienced an increase in cannabis operations with the start of the summer growing season.
A study involving the police and Environmental Science and Research released last month found that levels of THC, the primary psychoactive compound in cannabis, was more than four times stronger than in 1996 when ESR last tested it.
Police and ESR used sophisticated hydroponic equipment to complete three growing cycles, nursing six plants at a time to maturity. The study revealed the drug was more than four times as strong as in 1996.
Police believed that THC levels had increased significantly in recent years because criminals were using more sophisticated growing methods, helped by the availability of specialised equipment, such as that sold at hydroponic growing shops.