Maine officials are beginning to release thousands of beetles in a long-term effort to eliminate an invasive insect that is attacking hemlock trees in the southern part of the state.

The Department of Agriculture, Conservation and Forestry will release predator lady beetles at Baxter Woods in Portland next week to help reduce hemlock woolly adelgid, an invasive insect originally from Japan that can cause the trees to lose needles and branches and eventually die.

The department expects to release more than 10,000 beetles in various locations throughout the state over the next several weeks.

Allison Kanoti, a forest entomologist with the department, said ensuring the health of the hemlock trees is vital because they often grow near bodies of water and can filter pollutants out of the soil so they don’t reach the water system.

In addition, their shade plays an important role in regulating water temperature, which is essential for other insects and animals that feed on and live in the water, she said.

Kanoti said there’s evidence that the beetles have made a difference in other states, like Connecticut, but it’s unclear whether they will be enough to control the population in Maine and how long it could take.

Hemlock woolly adelgid was first found in Maine in 2003 and has been discovered in several parts of the state including Sanford, Bangor and Sedgwick, the department said. The white wool-like insects look like little cotton balls and are found at the base of needles on hemlock trees, it said.