Five tonnes of sticky molasses is leaking onto the road near Te Awamutu after a truck rolled.
It was carrying 14 tonnes of molasses before it rolled at 7.40am today on Ngahape Rd, Ngahape, south of Hamilton, an emergency spokesperson told 1 NEWS.
Day Dowd from Otorohanga District Council said no one had sustained injuries but the driver was "a bit shaken".
The leaking substance is the equivalent of 10,000 500g jars of molasses.
The syrup is used traditionally to make baked beans and gingerbread, according to Chelsea Sugars.