CARLSBAD -- Addressing a group of disappointed hikers Saturday, the president of a local nature group told the gathering that all hikes into the area known as Carlsbad Oaks North will be canceled, including the one that was planned for that morning.

Diane Nygaard, the president of Preserve Calavera, said she is halting all hikes because of a letter she received from the Techbilt Construction Corp., a developer and owner of Carlsbad Oaks North for about 30 years.

The letter states that any hikes organized by Preserve Calavera onto the property will be considered trespassing. Carlsbad Oaks North consists of 414 acres of land in more than 3,000 acres that make up the Calavera Wetlands.

"It was quite a surprise for us to get a letter from the developer," Nygaard said. "It is our intent to fully comply with that restriction."

Nygaard said that members of Preserve Calavera, a four-year-old grass roots organization of local residents intent on protecting the Calavera wetlands, have been hiking there since the organization was created.

Ted Tchang, the vice president of Techbilt Construction Corp., said he sent the letter to Preserve Calavera when he recently found out about the hikes. He said that the group never asked for permission to cross his property and he could not allow them to do so for liability reasons.

"They are pretty much treating the property like it's their own and I don't think that is right," Tchang said.

However, Nygaard said Tchang had a don't-ask, don't-tell policy regarding the hikes when she originally approached him about them four years ago.

"We didn't ask because, of course, he would say no," Nygaard said.

Despite the request from Techbilt to end the Preserve Calavera nature hikes, Nygaard said she would have been forced to discontinue them anyway. The property is tagged to become an industrial park that includes the extension of Faraday Avenue and El Fuerte in Vista, along with a sewer line.

During her explanation to the hikers, Nygaard encouraged them to write to Techbilt and City Council members to complain about the restriction and the future development.

Michele Jirek, one hiker who drove from La Mesa to participate in the hike, said that she was shocked when she learned that it was canceled. A member of the California Native Plant Society, San Diego chapter, she said that the Calavera area is home to many beautiful native plants and animals that residents will no longer be able to see if the industrial park is built.

"What is especially disturbing is that this area is possibly going to be lost forever and we can't even see it," Jirek said. "Everything is being covered over with buildings -- there is no respect for what makes California beautiful."