A tiny wasp known to destroy native wiliwili trees has been found in the remote Nu'u district of southern Haleakala, a significant blow to scientists trying to stem the insect's spread.

"It's terrible," said Andy Graham, owner and manager of Nu'u Mauka Ranch. "Nearly every wiliwili tree out there that I looked at that has leaves has got it."

The erythrina gall wasp, native to Africa, kills trees by attacking the leaves. The bug is believed to have arrived on Maui in the summer of 2005, and since has destroyed hundreds of wiliwili and coral trees on Maui and O'ahu.

The remote areas of southern Haleakala have extensive groves of wiliwili, a tree only found in the Islands.

"The wiliwili trees out here are big ones, many practically the size of monkeypod trees," Graham said, adding that he was walking in the groves last week "when I saw one infested tree and quickly realized that every tree out here has got that bug. I think until now I was in a type of denial. I thought maybe it would never get out here. I was wrong."

Scientists with the state and University of Hawai'i have found other insects in Africa that feed on the wasp — but the potential effects on Island plants and animals are still being tested.

"The wiliwili trees out here are beautiful; they are such a part of Nu'u," Graham said. "This place will be a desert without them. I just hope the cure can come in time."