MTT board chair Pat Turley said having Unison on board was a great step for the river project.
"MTT has been planting 11,000 to 15,000 native trees most years on the banks of the Maraetotora and with Unison's support, we will be able to plant 9000 native trees," he said.
"MTT has been planting 11,000 to 15,000 native trees most years on the banks of the Maraetotara, and with Unison's support, we will be able to plant an additional 9000 native trees over the coming three years. Unison is well suited given it's a community partnership, and the trust is excited about the financial and teamwork aspects the company will bring."
Unison relationship manager Danny Gough said Unison was looking forward to seeing the project "thrive".
"We see our sponsorship as a great opportunity for the company and our employees to help give back to the region at an environmentally sustainable level," he said.
"As a company involved in the management of — and directly impacted by — vegetation, we hope that through our partnership with the trust we can encourage and educate our communities to be safe about planting and maintaining trees near power lines."
Unison has joined David Trubridge, Turley & Co, Souness Stone and Clearview Estate Winery as permanent sponsors.