The tree-lined streets of Greencastle are now on OpenTreeMap.

A Student Conservation Association crew was in town Tuesday conducting an inventory of Greencastle's street trees.

The teens worked with tree identification books and tools for measuring features like diameter, then loaded the information and photos to the OpenTreeMap app.

The data can be used by the Borough of Greencastle to make informed decisions about the urban canopy and local residents who want to know about the trees, said John J. Schwartzer, Pennsylvania Department of Conservation and Natural Resources service forester for Cumberland and Franklin counties, who was with the group.

Greencastle is a designated a Tree City USA by the National Arbor Day Foundation, which means it allocates $2 per capita on the urban canopy, hosts an Arbor Day celebration and has a shade tree commission and a shade tree ordinance.

Schwartzer suggested the free inventory to Roger Johnston, chair of the shade tree commission, who thought it was a good idea.

Information on OneTreeMap also is available to members of the public who want to know what the trees are at various locations in Greencastle. For example, by clicking one green dot on the map, you learn there is a gingko (scientific name Ginkgo biloba) at 148 N.Carlisle St. Click another dot and you can see a Callery pear (scientific name Pyrus calleryana) at 150 N. Carlisle St.

The SCA crew, based in Fulton County, inventoried the street trees in Mercersburg Monday and also visited New Cumberland and Lemoyne this summer. They spent several weeks working at Cowans Gap and are wrapping up their seven-week program on a trail in Fulton County.

SCA is a nationwide organization with the mission to inspire and educate young people about the environment and to guide them into leadership, said Tricia Murtha. She and Tyler Watkins are leader of the local team of 15- to 18-year-olds.