by Carlos Correa

STOCKTON (CBS Sacramento) — Earl Summers and his wife Nancy were relaxing inside their north Stockton home when they heard something that sounded much like gunfire.

“All of a sudden we heard the biggest commotion I’ve heard. I didn’t know if it was an earthquake or a train running through the backyard. My wife jumped up and looked out the window and hollered, ‘oh my God!'” he said.

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An old oak tree next door, which had provided shade for 30 years, had exploded. Pieces of it were all over yards. One of those pieces broke through the Summers’ home.

“The limb just blew off. It was full of water which supposedly oak trees do — in the winter months they fill themselves with water so they can survive through the summer. We had no wind or anything. It was really calm and it just broke and came down,” said Summers.

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An arborist said such events occur during dry conditions when the temperatures soar. Just like people, trees sweat, a process called transpiration.

“Trees bring in moisture and they need to release that moisture. On hot, calm days when there is not a lot of wind, that transpiration — or sweat — decreases. The water is still being up-taken, but it’s not released so something has to give,” explained Justin Widgren, owner of NorCal Arborists.

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Neighbors are waiting for their insurance companies to assess the damage. In the meantime, they are helping each other clean up the mess left behind.