Mr MacRae said he was delighted to be involved with such a worthy programme, although sorry that because of his commitments with the NZRU he would not be able to take part in the August 17 planting at the estuary.
"It is a fantastic project that brings together rugby and conservation, and a privilege to be able to make a difference to New Zealand for generations to come."
He said he was "honoured" to be part of it.
After the August day, which will bring an end to the programme, volunteers will have planted 10,200 native trees throughout the estuary landscape. Throughout the country, 170,000 native trees will have been planted.
Volunteers wanting to take part must register their interest through the website, livinglegends.co.nz
Registrations for the Bay planting, which will take place between 9am and noon, will close on August 14.