TEWKSBURY — The world around the massive apple tree at 135 North Billerica Road has changed drastically since it was planted in 1977. Its owners have died, their children grown and married with children of their own.

But despite little in the way of tree care — pruning, watering, pesticide application — the tree has grown and thrived. And this year, it has produced a bumper crop — more than 2,000 apples, said Bob Ruest, whose in-laws, James and Harriet Alexandropolous, owned the property.

The tree was planted for Harriet on Mother’s Day by her two children, George and Athanasia, Bob’s wife.

“It was only probably a two-foot tree,” recalled Ruest, who was dating his wife at the time. “Apple trees don’t come big.”

It was the perfect gift for Harriet, Ruest said, because her yard was her pride and joy.

“If she had a choice between a tree and a car, she’d take the tree over the car,” he said.

For several years, the tree didn’t produce much. Harriet would pick the few apples that did grow and share them with neighbors, or make pies or applesauce.

Since James and Harriet died, the Ruests split their time between Athanasia’s childhood home in Tewksbury and their house in Londonderry, N.H. By his own admission, he hasn’t done much to maintain the apple tree, Ruest said. But he does attribute a few factors to its continued health — one being a friend with a water tank on his truck who came by a few times over the summer to spray the tree down on dry days.

“Nobody else has that option. That’s how I cheat,” he said with a smile. “No chemicals, no insecticide.”

The property also sits on former farmland and has rich, black loam soil, which has helped all the trees, grass and plants on the property to thrive.

“You could dig here, the biggest rock you’d find is maybe (the size of) a golf ball,” Ruest said.

Whatever the magic combination is, this year, the tree has reached maximum proportions. Last year, it maybe yielded 300 apples, Ruest said; this year, it has easily passed 2,000. As of Wednesday, Ruest estimated that about 600 were still hanging from the branches.

With so much fruit, the question becomes: What do you do with all of it?

The Ruests have eaten plenty of the apples, and Athanasia has made applesauce several times, but the bulk of the apples are shared. They give them to family, friends and neighbors. Athanasia brings them by the bag to share with her co-workers at Raytheon. Bob, an avid car enthusiast, passes them out at vintage-car shows, junkyards where he buys parts and auto-body shops he patronizes. He has also given many to the VFW hall in Billerica and the Lawrence Elks lodge, and to two local farmers who use the apples as feed for their animals.

“We horse-trade,” he said. “They’ve got a couple things I like, and one of (the farmers) has a brother with a property in Florida. I swap the apples for good oranges and grapefruit. No money’s made, but what the hell?”

The people he shares the apples with tell him James and Harriet’s tree produces delicious fruit.

“I’ve had some people say, ‘Bob, I can tell these aren’t from DeMoulas,'” he said. “Why? ‘Because they’re better.’ That’s what I like to hear.”

Follow Cassidy Swanson on Twitter or Tout @CassidyMSwanson.