More than a billion bees have hit the road in Tasmania.

The state's 185 beekeepers have begun trucking about 17,000 hives to the island's north-west, where bees will begin producing the world-famous leatherwood honey.

With up to 100,000 in each hive, that's a lot of bees — about 1.7 billion.

Producers are making their annual migration to Tasmania's rainforests, the only place where eucryphia lucida, commonly known as leatherwood, is found.

The white flowers the leatherwood plant displays from January to April are responsible for a $4 million boutique industry.