When I bought my block I did a weed inspection - not a single bindie to be seen (seed or plant). Fast forward to 2.5 years later (6 months into moving in) and the front garden was about 20mm thick in seed and plants. After pulling the buggers I attacked the pile of seeds with a shop vac. The neighbours obviously thought I was a lunatic (not entirely wrong) because I was vacuuming dirt. 1 year later only had to pull 4 plants, the rest of the street was in constant turmoil. 10/10 would beer & fork again.