DURHAM — ReTreeUS, a Maine-based project of the nonprofit United Charitable Programs, installed four educational fruit tree orchards this year, and has planted eight total educational orchards since 2012.

“The orchards are provided at no cost to schools,” says co-founder Moriah Salter, “and they come with innumerable benefits both for the earth and for participants.”

This year, Brownfield-Denmark Elementary, Freeport High and Oceanside-East High Schools received apple, plum, pear and peach trees from ReTreeUS. Wolfe’s Neck Farm also received a partnership orchard, meaning they shared the cost of the plantings, educational signage and programming with ReTreeUS.

“Mast Landing and Cricket Hunt schools in Freeport were among last year’s participants who received a few upgrades on their orchards this year,” says Richard Hodges, who founded ReTreeUS in 2011 along with his wife, Moriah.

“It’s made possible by members, sponsors and other financial supporters,” Salter says, “as well as our amazing volunteers and student participants. The kids are always so happy to be involved, and it’s gratifying to see them connect with each other, their food and the earth.”

Salter and Hodges founded ReTreeUS with a clear mission: to promote an environmentally sustainable, socially just food system by providing education, practical resources and mentorship. They plan to continue fulfilling this mission by planting four more educational orchards each year.

“Studies have shown immense improvement in the grades, behavior and social skills among students who participate in growing food at school,” says Hodges. “Teachers can also benefit from school orchards, since fruit trees can be connected to virtually every aspect of their curriculum.”

Along with the orchards they install, ReTreeUS also provides chemical-free produce at their farm stand in Durham, with pricing available on a sliding scale for income. “This helps fulfill another facet of our mission,” says Salter, “which is to create greater access to healthy foods and make good produce available to families of all income levels.” Individuals making less than $10,000 a year are eligible for their reduced-cost program, and all proceeds from the farm stand help ReTreeUS sustain and plant new school orchards.

Other support comes from grantors such as Jobs for Maine Graduates, the Captain Planet Foundation and the National Gardening Association, as well as members and sponsors like Fedco Trees, Wolfe’s Neck Farm, the Law Offices of Joe Bornstein, Home Depot in Windham, Skillins Greenhouses in Brunswick, Coast of Maine, Fedco Trees, Adams County Nursery, Fertil USA, Trees of Antiquity, T-Fencing Plus, Votenet Solutions and Waynflete School.

ReTreeUS is now accepting school orchard applications for the 2013-14 school year. Interested applicants should visit www.retreeus.org to apply.