This year, local schools will plant trees on Friday, July 25, and members of the community will take part on Sunday, July, 27.

A spokeswoman from Wollondilly Shire Council said since 1996 1.5 million volunteers have planted more than 11.5 million native trees and shrubs as part of the annual event.

``Wollondilly Shire Council will have a tree day site at Bargo Sportsground on Sunday, July 27,'' she said.

``Everyone is invited to join us from noon to 3pm to help plant some trees and there will also be a free barbecue.''

Wollondilly Mayor Judy Hannan said the council aimed to plant 1000 local native species trees on the day.

``The trees will be supplied by Wollondilly Community Nursery and 250 of those plants have been donated to offset the carbon emissions from our first green Australia Day this year,'' she said.

A spokesman from Planet Ark said tree planting made a positive difference to the environment.

``It provides an opportunity for schools, community groups and local residents to come together under the umbrella of one event,'' he said.

``Planting local native trees, shrubs and ground covers helps to provide food and shelter for Australia's wildlife, increasing native biodiversity and combating the habitat loss that threatens much of our wildlife.''

Tree day information: 46771177.