of remembrance , '' said Jeff Dietrich of Pennsylvania-based Joshua Tree , who has been volunteering for four years . A crew of arborists from the Joshua Tree company took on one the most expensive projects -- protecting Arlington 's biggest trees from lightning . According to Dietrich , the process of lightning protection is important for protecting a valuable part of history . Watch how trees are protected '' `` Lightning , electricity is unpredictable at best . ... It 'll blow a tree apart . '' To protect a tree from lightning strikes , Dietrich and his crew climb up to the top of a tree and run copper wires down the trunk with anchors that resemble rifle cartridges . The wire is then grounded by a copper pole entrenched at the base of the tree . If lightning strikes , the electricity runs down the wire and dissipates into the ground instead of harming the tree . Even though it took the Joshua Tree crew longer to reach Arlington from Pennsylvania than the four hours needed to complete their work , the workers seemed eager for their chance to volunteer , cheering each other on while working
ARLINGTON , Virginia -LRB- CNN -RRB- -- The hallowed grounds of Arlington National Cemetery took on a different tone Monday -- the usually quiet and reverent resting place of fallen heroes was buzzing with volunteers , professional landscapers and their equipment during the annual `` Renewal and Remembrance '' project . Monday was the annual `` Renewal and Remembrance '' day at Arlington National Cemetery . `` Renewal '' was started more than 10 years ago by an Ohio lawn-care group that wanted to give a day of service to the cemetery outside Washington , according to Bill Hildebolt , spokesman for the Professional Landcare Network . `` It 's grown fantastically from a few lawn-care operators to today we had over 400 individual PLANET members , '' he said Monday . Each year , volunteers take on several projects during the service day , including spreading lime over nearly 300 acres of the cemetery and installing irrigation systems , Hildebolt said . While the 95 companies participating Monday may normally compete for business in the lawn-care market , during Renewal the crews work together to honor the service members buried at Arlington . `` It 's just a day