This shrub has become one of the worst weeds in recorded history, according to a 2012 PLOS One study by researchers at the University of Oxford. You’ve probably walked past lantana without a second thought. With its tiny, brightly colored flower clusters, it appears to be a perfect garden plant. People grow it for its bright blooms, but may not consider how quickly it can spread. It got out of gardens in Australia and spread over the land. Queensland has paid a heavy price for that.
Opportunity cost is money lost when land isn’t used as well as it could be. It must not be given away, sold or released into the environment. The largest cost figure the study reports comes from farming . Note that those two values are from different sources, so the comparison is rough. Lantana is now recognized as a serious problem in Queensland. Landowners are responsible for its impacts. The Oxford team points out that invasive species may not always be a target for eradication, and future plans may need to be geared toward adaptation. The lesson is a simple one: a plant that looks harmless in a garden can become a lasting problem once it escapes.
The study cites a 2003 assessment in Queensland in which lantana was ranked the most invasive weed. Control of lantana in Queensland cost an estimated A$1 million per year in 1973. One analysis of Queensland’s grazing sector put the opportunity cost of lantana at A$121 million in 2007. In 1985, the figure for the same sector was A$3 million a year. The Queensland Government has it listed as a restricted invasive plant of category 3 under the state’s Biosecurity Act 2014. The government says it covers 5 million hectares in Australia.
