Question: Why are the kiawe trees dying along the Leeward Coast? Several weeks ago I noticed the branches/leaves on the trees on the ocean side of Farrington Highway appeared to be drying up/dying and now have spread to cover entire trees. Some other types of trees now appear to be experiencing similar deterioration. Because the deterioration started on the makai side, I thought maybe it had to do with the ocean spray, as we have had some large wave action recently. But this occurs every year, and we never saw it affect the trees like this before. My concern is that the condition was caused by some herbicide or chemical contamination.
Answer: Tree experts agree that it is the prolonged presence of wind blowing in from the west, not any chemical contamination, that’s damaging the kiawes along the Leeward Coast.
Unless the heavy wind continues unabated, local arborist Steve Nimz said the trees should be able to recover.
"These winds typically last a day or two, but have been present as much as 10 days straight," explained Jeanne Ishikawa, deputy director, city Department of Parks and Recreation, which includes the Division of Urban Forestry.
About half of the days since Christmas Eve have had this westerly wind, she said.
Bernarr Kumashiro, an entomologist with the state Department of Agriculture, is an insect expert but knows trees because insects are often blamed when trees start dying.
He cited salt spray, coupled with very strong winds blowing in from the ocean, for damaging the kiawes.
"Years ago, when we had Hurricane Iniki, I saw the same thing happening at Honolulu Zoo, which is close to Waikiki Beach," he said. "The mock orange hedge was burnt on the makai side (facing south), while the mauka side still was green."
Several weeks ago "we had very strong winds blowing in from the west, which is unusual," Kumashiro noted. "So it would be the Leeward Coast that got hit hard."
The Windward side also got hit, but that was from west wind going over the Koolaus, he said.
"The strong winds can only carry the salt spray so far, so trees on one side of Farrington Highway may show lots of damage while across the street on the mauka side, damage may be minimal," Kumashiro said.
What’s happening to the kiawes is not that unusual, said Nimz, who has more than 40 years of experience in the field and is a charter member of the Aloha Arborists Association. It occurs at least once or twice a year, although it’s "a little bit more severe" this time, he said.
"The salt spray just really burns (the leaves) off," Nimz said, describing it as a "soft burn" that starts on the ocean side. If the culprit were chemicals or herbicides, "it would be all over the whole tree at once, not just on one side."
The problem is much more common on the Leeward than the Windward side of the island, he said.
Will the trees be able to recover?
Ishikawa said it’s hard to predict what the end result will be, with much depending on how much longer the west wind lasts and whether it starts up again.
"Some species will tolerate these weather conditions better than others," she said. "Even before the unusual winds, the trees were already stressed from the drought conditions on the Leeward side. The Division of Urban Forestry will continue to monitor the trees."
Nimz was more optimistic.
As long as major, heavy winds don’t continue, he said, "You’re going to see, probably within a month or so, new leaves popping out on all those trees. … Those trees can handle about two to three events like that a year but not much more than that. But they’ll be fine."
Mahalo
To Crisna Magday. We seniors were surprised when the waitress at Anna Miller’s said Crisna had picked up our check. — Mr. and Mrs. C.
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