GUILDERLAND — Laura Shore of Guilderland found out the hard way that the beautiful ornamental plant growing in her yard was toxic giant hogweed: by trying to prune it.

Now her home at 751 Route 146, just outside the village, is the only site in Albany County that the Department of Environmental Conservation currently monitors to be sure that giant hogweed does not return. There are 1,681 sites being monitored throughout the state.

Shore and her partner, Nancy Ota, purchased the old Inn of Jacob Crounse in 2007. At the time, the house and garden were both “pretty run down,” she said.

The lush, shade-loving plants growing behind the garage — with their huge leaves a foot or two across and stalks at least an inch in diameter — reminded her of the Maurice Sendak children’s book “Where the Wild Things Are.” She thought how much fun it would have been to have grown up around that plant and been able to use the stalks for swordfights.

She asked the sellers of the home what the plant was, “because I thought it was cool-looking.” It was angelica, they said.

She filed the name away in her memory and meant to look it up online at some point, but soon, busy with home repairs, forgot all about it.

Shore and Ota moved into the home in 2008. That summer, the plants had grown and were “pretty robust,” but the women were “pretty preoccupied with working on the house.” The winter of 2008-09 was really snowy, and there was a lot of rain during the summer of 2009, Shore said, so “it just luxuriated.” It was in August 2009, when the stalks were so tall that they had fallen over and broken, that Shore decided to try to prune back the plant.

The weekend that she chose for pruning was hot and sunny. “That evening I noticed the beginning of painful blisters on my legs and hands,” Shore said.

At first she thought they might be from poison ivy. “But they didn’t itch. They hurt like burns.”

A day or so later, she got a telephone call from a contractor who had recently done some work on their home and been so intrigued by those plants that he had asked Shore and Ota to give him some seeds.

The contractor was calling to say he had just received a copy of Conservationist Magazine in the mail and read a story in it about giant hogweed and how dangerous it was.

He recognized it as the plant he had admired at their property and wanted to let them know what they had.

Shore started doing some Internet research and realized that her burns were from giant hogweed.

“We alerted our lawn crew to stay away from the plants and called the Department of Environmental Conservation,” Shore said.

Officials there asked her to send photos, which she did. A crew came out within a week, she said.

The plant is phototoxic, which means that, when its sap comes into contact with skin in conjunction with sunlight, it can cause large, painful blistering burns, according to the DEC website. If the sap gets into someone’s eyes, blindness may occur. Sap can be located in all parts of the plant.

When a site is found, DEC officials in hazmat suits come out to remove the plants and seeds, said Naja Kraus, who coordinates the Giant Hogweed Program at the Department of Environmental Conservation’s Division of Lands & Forests, Forest Health.

When a group of workers are controlling plants together, they make certain to stand a good distance away from each other, since sap can splash three to four feet, the DEC website says.

If it’s a small site, of 400 plants or less — including seedlings — the plants are root-cut. For sites larger than that, herbicide is used, Kraus said.

The most common place to find it, Kraus said, is at historic homes like Shore and Ota’s, where it has been brought in at some point as a dramatic ornamental plant.

Seeds are not windborne over large distances, said Kraus, so it’s not likely to waft in from far away. It could encroach if a neighbor were to have a lot of plants. If a site with plants sits beside a stream, seeds could float downstream and propagate in new areas, Kraus said.

It takes years of monitoring to make sure it is eradicated, said Kraus. Once it is controlled, officials go back for between three and five years, until they have had no plants at all for three years running.

“At that point we declare it to be eradicated,” Kraus said. But they’re still not finished. “We go back again three years later. If there are still no plants, we go back once more, three years after that.”

So it takes at least nine years to go through the entire cycle, Kraus said. The DEC monitoring program is currently in its ninth year. “So we have not reached that point with any sites yet.”

Kraus was not sure what would happen if, at that ninth-year visit, there were still no plants. “I assume that at that point we would say it’s good, and leave it up to the homeowner to contact us if there should be any future problems.”

Shore could not remember just when the DEC would be finished checking the yard of her home.

When asked the current status of Shore and Ota’s hogweed —whether the DEC would be making any more visits to the home — Kraus said that she could not confirm just where a property was, or who owned it, but reiterated that they are currently checking just one property in Albany County.

The last time any plants were found at that property was in 2013, adding that in many cases these will amount to just one or two seedlings.

She said, “We’ll go back to that property in 2016, and if we don’t find any, we’ll consider it eradicated, and go back again in 2019, just in case.”