Joan McHenry Hoblitzell, a naturalist, equestrian, hiker and volunteer, died of heart failure Oct. 28 at Greater Baltimore Medical Center. She was 82.

“I wish that the whole world had gotten to know her. I loved her so much, and she was a heroine to me,” said Pooh Douglas, a friend from high school and college who lives in Narragansett, R.I.

“She was loyal, a wonderful friend and a great lover of people. She loved her family and was wedded to her farm in ‘The Valley,' as Baltimoreans call it,” she said.

“She was very passionate about the environment and nature — and that's why she came to the Irvine Nature Center where she was still taking courses,” said Robert Mardiney, director of education at the Owings Mills center. “Her death is a big loss. She loved Irvine and we loved her.”

The daughter of James McHenry, an investment banker, and Marjorie Hambleton Ober McHenry, a homemaker, Joan McHenry was born in Baltimore and in her early years lived at Dunlora, an estate near Park Heights Avenue. In 1951, the family moved to the Upper Green Spring Valley.

Mrs. Hoblitzell's mother described her as independent, imaginative, intelligent and mischievous as a young child, said a daughter, Marjorie Hoblitzell “Mo” Baldwin of Annapolis.

She was a descendant of James McHenry, for whom Fort McHenry is named. He was a signer of the Constitution and a member of the Continental Congress. He served as the nation's third secretary of war, from 1796 to 1800.

After graduating from Garrison Forest School in 1952, she earned a bachelor's degree from Vassar College in New York in 1956. Later, she studied to become a certified public accountant.

Mrs. Hoblitzell became an accomplished horsewoman at an early age.

“She rode horses as naturally as she walked,” her daughter said.

“I first saw Joan in 1948. I was down in Maryland looking at potential boarding schools and was taken to Garrison Forest — as I was horse-mad,” Mrs. Douglas recalled. “Of course, I was there during Hunt Cup. I saw Joan was kneeling near the 13th fence where her horse Dunlora had fallen. Dunlora was so badly injured that she had to be euthanized.”

Mrs. Douglas decided to enroll at Garrison Forest, and “the first thing I did when I got there was look up Joan,” she said.

“We became close friends, and our senior year we boarded together. We then went to Vassar, where we boarded together for four years,” she said. “She was always strong — spiritually strong, brave and funny.”

Mrs. Douglas said her friend won the Green Spring Old Fashioned competition in 1966. She said one of Mrs. Hoblitzell's memorable moments in racing came when she finished last at an Elkridge-Harford Hounds Ladies' Race on her mount, Wild Bill — what was most important was the fun she had “being on the field of play that day,” Mrs. Douglas said.

After graduating from Vassar, Mrs. Hoblitzell took a job with the Rouse Co. and worked closely with Edwin A. “Ned” Daniels, who later became a vice president of the company and created and developed its Art in the Marketplace program, which introduced live music to Rouse Co.-owned malls.

After her marriage in 1957 to Alan Penniman Hoblitzell, she and her husband settled into a farm on Green Road in Glyndon, where she lived until moving to a farm on Mantua Mill Road in 1985.

“Her deepest connection would always be to the land,” her daughter wrote in an email profile of her mother. “When she owned her farms, you could find her out on the tractor mowing fields, hauling trash, digging out streams or any of the other never-ending tasks in the country.”

Interested in land preservation and a strong advocate of protecting the rural countryside from development, Mrs. Hoblitzell became an active member of the Green Spring Worthington Valley Planning Council.

Continuing her interest in the outdoors, she became a trained volunteer naturalist at Irvine Nature Center, and through the years led hundreds of school field trips for students ages 3 to 16 through the forests and meadows that surround the center.

Mrs. Hoblitzell would often bring to the center things she found in her yard — plants, insects, seeds, a praying mantis egg case, a nut, or a polliwog.

“Her curiosity was contagious,” her daughter wrote.

“None of our volunteer educators has more passion about the subject matter and their presentations than Joan,” wrote Mr. Mardiney in a 2013 letter recommending Mrs. Hoblitzell for a Garden Club of America scholarship.

He recalled this past week her passion for nature and education, and said when she was working with young children, “she'd get down on her knees and show them objects.”

“She also worked in our deer-proof woodland garden. Not only did she purchase the plants, she planted them,” Mr. Mardiney said. “A couple of weeks ago, she came by with wildflower seeds and planted them.”

Mrs. Hoblitzell was an active member of the St. George's Garden Club and had had served as its president from 1991 to 1993.

She was a member of the Baltimore Symphony Orchestra's Young Associates, a group that organized children's concerts.

She was a longtime active communicant of St. Thomas Episcopal Church, where she helped with the church's account books. She was also a Greater Baltimore Medical Center volunteer.

Mrs. Hoblitzell enjoyed spending summers in a cabin at Squam Lake in New Hampshire, where she indulged her passion for hiking. During her lifetime, she climbed every mountain higher than 4,000 feet in New Hampshire's White Mountains.

At the end of a successful hike, it was Mrs. Hoblitzell's custom to sit with a drink and listen to the loons calling on the lake.

“We started hiking together in 1980,” said Tockie Baker, who lives in Lutherville. “She was a very enthusiastic hiker and we liked climbing the White Mountains together. She was a very positive and upbeat person who enjoyed life.”

In August, she drove to Springer Mountain, Ga., where she walked the beginning of the Appalachian Trail.

“She never stopped hiking — the distances just got shorter,” her daughter said.

Since 2008, Mrs. Hoblitzell lived in a townhouse in Ashland in Baltimore County.

She enjoyed entertaining at dinner parties and sharing time with her many friends.

“She never stopped thinking of other people. She was the most giving person I've ever known,” Mrs. Douglas said. “She would deflect questions about herself and change the subject. She didn't want to waste time.”

A memorial service will be held at 11 a.m. Friday at her church, 232 St. Thomas Lane, in Owings Mills.

In addition to her daughter, she is survived by two other daughters, Jean “J.B.” Hoblitzell of Roland Park and Priscilla Hoblitzell of the Worthington Valley; a sister, Margie Bride of Boston; and a grandson. Her marriage to Mr. Hoblitzell, former chairman and chief executive of MNC, parent of the old Maryland National Bank, ended in divorce.

frasmussen@baltsun.com