Brisbane City Council is investigating what caused a branch of large leopard tree to fall on Ann street outside City Hall, blocking two lanes and the footpath on Monday.
A spokeswoman for Lord Mayor Graham Quirk said the council is currently investigating the causes behind the fallen tree, which was inspected in late February with no identifiable issues.
Police blocked the two lanes of the four-lane Ann Street and managed the scene for more than two hours as the council attempted to source an arborist and removal equipment late on a public holiday.