Weeds – some are worse than others – but why?

Our weed of the month for May is not a big threat at Cape Jervis – yet, and maybe never, but we will watch and act if necessary. The worst important weeds for any given area can be different but there are formal processes for classifying weeds. There are 32 weeds that have widespread impact, and are listed as “Weeds of National Significance”, based on their invasiveness, potential for spread and environmental, social and economic impacts (http://www.environment.gov.au/ biodiversity/invasive/weeds/weeds/lists/wons.html). We have two of these on site, bridal creeper and boxthorn. Each state also has its own “Declared Weeds”, that land holders are required to control on their own land (http://www.pir.sa.gov.au/biosecurity /weeds_and_pest_animals/weeds_in_sa). Other weed threats, such as Acacia cyclops are more localised. Woody weeds such as olive and cyclops are a BIG problem in the biodiverse coastal heathlands at the Cape because of their rapid growth and their smothering effect. Come out with us for a few hours and we can show you the benefits of removing these weeds and help you recognise young seedlings so they can be removed before they become a big problem.

Photos: hand-pulled ‘cyclops’ seedlings (E. Cousins); resprouting poisoned olive; a sea of baby olives (C. Schultz).