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Walking around our neighborhood (Orchidland) I've noticed a number of dead Ohia recently. These are not on ripped lots so the roots have not been disturbed. They are on untouched lots and some are quite old.
In most cases it is individual trees among others that seem fine although there are a few clumps of a number of dead trees.
Is this old age? How long does an Ohia live? A reaction to vog? Something else?
Jerry
Art and Orchids B&B
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We've noticed the same thing on our property..trees that don't look particularly old now look particularly dead. Would love to hear other folks' ideas.
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Might be ohia rust (Pussinia psidii) that has be very evident in the last couple of years with elimination of rose apple (an introduced invasive) around the islands... I know that this was one of the pathogen introductions that everyone involved reforestation at UH-Hilo was most worried about... it's effects on the ohia could be devastating....
It may be a good idea to let HEAR or the ag branch at Komohana know if you see this rust on any stands of Ohia
The HEAR Llink of links including many images is:
http://www.hear.org/species/puccinia_psidii/
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A friend of mine from the UH cooperative extension came out to look at the forest near where I live recently. He had been called to see some other dying ohi'a's on another property in lower Puna. It seems a lot of ohi'a's are dying in lots of places and it started before the worst of the drought set in. None of these ohi'a's my friend saw had any rust. Actually, I didn't realize that the rust which specifically targets ohi'a's had made it here to the BI. (Carey, maybe you can fill me in on that one.) There is a harmless native gall wasp that makes red-orange raised galls on ohi'a leaves, which I suppose could be easily mistaken for rust also. My friend said that most all of the ohi'a's he saw were badly overrun with strawberry guava and other weeds, and he believes that's what is doing them in. It does seem like a whole lot of them have died suddenly, but whenever there is drought or other stress, the weeds tip the balance and a lot seem to go at once. My pal also said he didn't think it was the phenomenon known as cohort die back. It really is distressing. I'd be interested in anything else anyone finds out.
Mitzi
Uluhe Design
Native Landscape Design
uluhedesign@yahoo.com
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The guava indeed seem to be choking out the Ohia. It has been mentioned to me that the guava are very heavy water consumers and thick guava can cause the Ohia to die of thirst.
No, I am not an expert.
Assume the best and ask questions.
Punaweb moderator
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Just to be the devil's advocate, why now? The guava has been here for almost 200 years.
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I have several ohia trees in my yard and about 30% are either dead or dying. The others are very healthy as far as I can tell. I don't think it's anything I'm doing because in the few hundred yards between my yard and the ocean I see the same thing and that's on untouched and undeveloped land (Kaloli Point, HPP).
None of my dead or dying ohias are being strangled by guava so I don't think it's that plus the guava isn't growing around those in the undeveloped land.
I know one or two have been hit by lightning in the last few years and that'll kill a tree in a heartbeat but I'm at a loss to explain why my ohias are on their way out.
It might be climate change but I don't think it's vog because ohias have survived that for decades/centuries. It's a complete mystery to me, I hope someone figures it out.
Tom
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I have land in Eden Roc. There is pahoehoe with little soil, lots of uluhe ferns, lots of waiwi. There are lots of scraggly ohia. There are some younger ones that are quite healthy. There seem to be lots of old ones that are not dead but that are barely alive. They look like they nearly died in the past, with broken off tops and only a little foliage on the odd branch. As I drive around Eden Roc I lament that everyone seems to have bigger and healthier trees than I do. Because of how close these other trees are I assume that the difference is not weather related. I assume that the major difference is that I must be on top of a lot of pahoehoe, although that doesn't explain why my trees seem to have grown well and large at some time in the past but are languishing now.
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I've lost several of my ohia in the past year; no guava at all in my yard but I have the rust fungus so bad on my trees that I power-hose them every now and then to get it off the ohia. The ohia that died were smaller ones, not my big, beautiful ones.
Ag specialists told me it was the rust fungus from the ohia that was killing the blossoms on my mango tree. They also said if I couldn't spray my ohia trees (several of which are like 35-50 feet tall), there was no cure for the rust fungus. I don't think the fungus is killing the ohia or other trees because I still have most of my trees and they're blooming and seem quite healthy looking, except for the rust.
One thing that does kill ohias is concrete poisoning. I've seen some homes in my neighborhood where people kept an attractive stand of ohia but then put in a concrete driveway or walkway and the ohia all died. If only they'd known...
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