Measuring a property’s perimeter for a new fence can be hazardous to your health.

Potential dangers include but are not limited to stepping in an unseen hole and spraining an ankle, disturbing an underground yellowjacket nest resulting in a pantlegful of angry hornets, and perhaps tripping over an old, rusty, hidden strand of barbed wire and taking a hard, injurious fall.

Then there’s the problem Whately fence contractor Dan LaValley encountered in April – one he wasn’t expecting.

Walking a measuring wheel to determine the length of the back property line for the last house on Juniper Drive in the Pine Nook section of Deerfield, the L&L Fence Company general manager’s tool hit something concealed in six-inch, unmowed spring grass and got stuck. Not an uncommon occurrence; he paid little attention, figuring he had flipped a stick that hit his measuring device.

He soon learned otherwise, discovering it was in fact not a harmless stick. He had disturbed a timber rattlesnake, stretched out near a Goshen-stone wall.

“I looked into the long grass, heard a rattle, and saw a snake curled into a strike position,” he said. “So I, of course, jumped back, then actually finished measuring.”

LaValley went to his truck to retrieve a six-foot level and his cell phone before returning to the scene and finding that the black, four- to five-foot rattler hadn’t moved far. He stood back and snapped off a few photos of it stretched out in the grass. When the snake curled into a defensive pose and rattled, LaValley snapped off a blurry shot of its head, ready to strike out in front of its coiled body, recorded a short video of it rattling, and vacated the scene.

He showed his video and photos around in the days that followed, but had erased them from his phone by the time I got wind of the incident on the Fourth of July and queried him by email soon thereafter. He was, however, able to recover two photos from his computer, and emailed them to me. One showed the beautiful, black rattler stretched out in the grass. The other displayed it coiled and ready to rumble.

“I’m not a snake guy, lol, and usually run in the other direction,” he wrote in a subsequent email. “I deleted the photos and video from my phone because I got sick of scrolling past them.”

Among the many people he showed his evidence to was an Environmental Police Officer friend who confirmed it was a rattlesnake. It was likely hunting mice, chipmunks, and red squirrels in a feeding lair near the tidy, modern stone wall about 40 feet from the house. In April it would have recently come out of a winter den populated by several other rattlers. Snakes come out of hibernation in the spring hungry and ready to feed through the forest and meadow.

So, take it to the bank that this mature snake was not a solitary traveler – there are undoubtedly others nearby. But you’d have to be very unlucky, or stupid, to get bit. Timber rattlesnakes, which run in color from black to various shades of brown, are endangered species in Massachusetts, and thus protected. They avoid conflict if possible. State law forbids people from harassing, chasing, disturbing, capturing, harming, or killing timber rattlesnakes.

As it turns out, this recent Deerfield Mountain sighting was personal vindication of sorts for me. Many years ago during this millennium, I wrote a series of Greenfield Recorder outdoor columns about rattlesnakes. Although my impetus is irrelevant, it was most likely related to a hike I took with a friend and a Mount Holyoke College geologist to the summit of Mount Nonotuck, which overlooks Northampton from the south. We were there to investigate a long-forgotten lithic chert source once mined for stone tool material by ancient Native Americans from our slice of the Connecticut Valley.

Nonotuck is the southernmost ridge of the Mount Tom Range, which curls south toward West Springfield along the western shore of the Connecticut River and is one of the state’s strongholds for venomous rattlers and copperheads. This I knew as we poked around on a high lonesome talus slope.

I was also aware, from historical research, that rattlesnakes were common “inconveniences” throughout the Connecticut Valley and most of early New England through the 19^th century, and that they are associated with talus slopes.

When I wrote about rattlers in Franklin County locations like the Pocumtuck Range in Deerfield, Rocky Mountain in Greenfield, and nearby Rattlesnake Mountain in southern New Hampshire, across the river from Brattleboro, Vermont, many readers a generation older than me chimed in with personal rattlesnake recollections. One respondent, a woman, wrote of a well-known den on undeveloped land around today’s Cherry Rum Place in Greenfield. Another source identified the rocky ridge from Poet’s Seat Tower to the mouth of Fall River as a Greenfield hotspot.

My own cursory research identified the Mount Toby range in Sunderland, Montague and Leverett as a known rattlesnake lair, with North Leverett’s Rattlesnake Gutter still displayed on maps.

Given what I had heard from emailers and knew from my own travels – including a personal encounter during my land-surveying days with a nest of rattlers basking on sunny ledge along the Mass Pike in Russell or Becket – I wrote that someone who knew where to look could likely still kick up a rattler along the eastern slope of Mount Sugarloaf, or on a secluded shale bed I know in the Conway State Forest.

In response to that prediction came an email from a trail runner or hiker who often toured the Deerfield Mountain ridge trail between the Eaglebrook School ski slope and Stage Road in South Deerfield. There he claimed to have encountered a big rattler crossing the trail in front of him. Intimately familiar with that ridge trail myself, I asked him to pinpoint the sighting. He located it near a threatening “No Trespassing” sign warning violators that survivors would be prosecuted.

That’s all I needed to know. The signs were those of my childhood friend “Fast Eddie” Urkiel, a notorious game bandit widely known and aggressively pursued by game wardens till the day he died. His woodlot’s southern boundary, marked by that threatening warning, is less than a mile up the hill to the west from LaValley’s encounter.

I rest my case.

Was it not predictable that timber rattlers would ride the comeback trail to Franklin County due to reforestation and global warming? Now it’s advisable to learn where dangerous snakes lurk. It’s wise to be cautious, not terrified. We can co-exist just fine, thank you.