HARVARD -- Sean Bilodeau, owner of Acorn Tree and Landscaping Service of Harvard, waited until the time was right. That time was Monday morning.

That's when a crane sporting a 150-foot boom set up in the Shaker Cemetery on South Shaker Road. The task at hand was to fell eight massive white pine trees. Each measured some 50 inches in diameter and was estimated to be at least 80 years old.

The work had been contemplated for months, but the temperature had to be cold enough to ensure the ground would be frozen and capable of handling the heavy equipment without caving in any burial grounds that may have settled overtime.

"We'd been checking it the last couple of weeks," said Bilodeau. Last week's bone-chilling temperatures with sustained readings below freezing helped. "As you can see, there's very little compression of the earth."

There was little snow cover on the ground when the work began. An inch of snow began to fall late Monday.

"If we had snow, we were actually going to come in and plow the snow off," said Bilodeau. The season's earlier snow cover had acted as an insulator and had prevented the grounds from freezing, Bilodeau said.

Cemetery Commission member Jack Spero said Tuesday that the work was completed and no damage was sustained to the historic and hallowed grounds during the operation.

The trees posed a threat, which was partially realized overnight between Oct. 29 and Oct. 30, when the after-effects of Hurricane Sandy blew through the area and snapped one of the pines mid trunk. The massive canopy of the tree fell across several rows of the cemetery's so-called lollipop-shaped cast iron grave markers.

Seven markers were damaged in the October storm; two were shattered into multiple pieces, four were broken into two pieces, and one marker was separated from its ground post.

In advance of the tree-removal project, cemetery commissioners had removed all 240 lollipop markers and replaced them temporarily with numbered wooden stakes. Stone markers toward the front of the cemetery were left in place during the tree-removal operation.

Seventy-nine markers that had previously been restored under the Cemetery Commission's lollipop marker preservation program are being stored at Fruitlands Museum on Prospect Hill. The balance of the markers are awaiting cleaning, repair where needed, and powder-coating at Central Mass Powder Coating in Clinton before they're re-installed at the cemetery this spring. None of the recently-preserved markers were damaged in the storm.

Shaker historian Roben Campbell advised the commission in November that the Harvard Shaker Cemetery is the only known surviving Shaker cemetery with lollipop markers. The last burial in the cemetery took place in 1929. The town has since taken title to the cemetery.

Acorn Tree Service was the low bidder for the tree-removal project at $11,500, which included crane work and stump grinding. Spero said the eight trees were all removed this week. Bilodeau said the stump grinding will be performed at a later date with an eye towards preserving the land slope within the cemetery.

Bilodeau figured the eight trees were not intentionally planted in the cemetery because of their random location. Rather, Bilodeau said the pines are natives of the area which likely took root where their seeds fell.

Dropping the trees directly onto the earth with chainsaws was not an option, said Bilodeau, since the trees were so massive. Instead, a treeman with a chainsaw tied to his utility belt was tethered to the crane's ball and elevated into the tree canopy to cut the tree into large segments which were then lowered onto the ground and chipped into a waiting truck to be hauled away.

"There was a lot of rot," confirmed Bilodeau. "This wood isn't lumber quality. Some of these trunks are hollow."

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