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ohia have probably been here for millions and millions of years. the oldest seamounts near the aleutian islands, which drifted there from here, are close to 90 million years old. who knows how many older seamounts have been subducted prior to those? at any rate, just because kilauea is only 500K years old, doesn't mean that's when ohias were introduced. they're on all the other islands, and likely jumped from one volcano to the next as it erupted. eventually loihi will be above the sea, and ohia will make their way over there. so ohia was definitely here before man. probably before man even walked this earth.
I knew if I asked a question, the great punaweb members would give some very informative answers. Thank you. Bluesboy, I thought this same way about the islands and the Ohia. The Ohia may be a sensitive tree in some ways, also very strong in comparison to other trees when living on or near volcanoes and lava?.
Delta9r, Thank you for the informative answers. What intrigues me most though may be your views of large portions of land away from roads (your overflights)?. I agree with you about the complexity part too(that's killing trees), Would you agree that the causes COULD be man induced Geothermal, agriculture practices, cell towers, electricity, ect?. Or do you think its natural causes like volcanic, drought, or bugs and disease?. Or combination of both?. You seem to have a good view and an open mind.(thank you). P.S do you ever take pictures on these flights or can you get some good maps that shows this progressive die back?.
Rob, I don't think your Ohia trees are dead or dying from the suppressing Gauva, or the fern that grows around them. Because all that foliage does is hold and retain water longer for the larger Ohia's. J.M.O though. I hope they bounce back or stop dying too.
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While I don't like quoting Wikipedia, this may be of interest. The Ohia tree we know is unique to Hawaii. It has adapted from it's cousins to life here.
As far as the die off, I have spoken with many experts and there is no one consensus on why. Likely a number of factors.
There are about 50 species in the genus Metrosideros in Southeast Asia and the Pacific, including four other, much more localized species in Hawai#699;i - M. macropus (lehua mamo), M. rugosa (lehua papa), M. tremuloides (lehua #699;#257;hihi), and M. waialealae (Wagner et al. 1999). They are easily confused with M. polymorpha, and are best distinguished by their leaves.
Metrosideros kermadecensis, from the Kermadec Islands north of New Zealand, has recently become naturalized on Maui and may become a pest species. Several cultivars of M. excelsa, the P#333;hutukawa tree of New Zealand, have been sometimes planted as ornamentals in Hawai#699;i but are not reported to have naturalized. Metrosideros polymorpha was originally classified as a variety of M. collina, native to Rarotonga, Tahiti, and other islands of Polynesia, but now is generally accepted as a distinct Hawaiian endemic species.
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I stole this from Wikipedia too!!!
Metrosideros polymorpha forests in Hawaii have been invaded by a myriad of alien species. In the wet forests these include the strawberry guava (Psidium littorale), albizia (Falcataria moluccana), and "purple plague" (Miconia calvescens). In drier areas, problematic invaders include faya tree (Myrica faya) and Christmasberry (Schinus terebinthifolius). Alien grasses such as meadow ricegrass (Ehrharta stipoides) may form an understory that prevents or inhibits natural regeneration of the forests. In drier areas, M. polymorpha has to compete with silk oak (Grevillea robusta) and fountain grass (Pennisetum setaceum). While Ohia itself remains extremely abundant, some species that depend on it such as the (Loxops caeruleirostris) and longhorn beetles in the genus Plagithmysus have become endangered due to shrinkage of forest areas.
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OK, don't mean to flog a dead pua'a, but I didn't know what geo-engineering was till a month or few ago due to apparent media ignore-ance. IMO possibly relevant to stressed aina occurrences.
Lots of stuff on YouTube on the subject, but a really good intro is the dvd "Why In The World Are They Spraying?" which includes some local input. I'll be returning it to the Keaau Library today so might be available after 2 PM.
Aloha aina, aloha kai
Aloha aina, aloha kai
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One of the reasons we chose the OL lot we did was because of all the awesome ohia. Questions:
How far from the trunk do the roots spread, generally?
If there are invasives growing right alongside the ohia (we have lots of strawberry guava and princess flower) what is the best approach- to uproot the nasty and risk messing with the ohia's root system, to cut down the invasive but leave the stump in place, or just leave it all together?
Do ohia like mulch? (Their roots seem very exposed.)
What are some good understory plants we could be planting?
Mahalo!
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Regarding the date of human arrival in Hawaii - the reason there is conflict over this is because of the poor condition of most of the earliest human habitation sites. The layers tend to be more disturbed and mixed up as well as contaminated with non-human-influenced material, which means that carbon dating charcoal has high error bars. So a study was done a few years ago where they took only the best, cleanest samples with narrow error bars, and found that the earliest ones were from ~1200 AD.
There are several problems with this (aside from contradicting the story of Paao, which is uncertain regardless), namely 1) several of the older sites are unequivocally from between 300-1000 AD even if it's hard to pin down exactly when in that range, and 2) it would require an extremely accelerated rate of population growth, land development, and social evolution to get from a relatively small number of colonists in 1200 to the highly complex feudal and agricultural system that existed by at least 1500 if not earlier.
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quote:
Originally posted by gypsy69
Hawnjigs, I thought similarly for a few years now. (the story is they died naturally-dieoff). We did get 2 or 3 really good rains the last 4 months, since the rain I have seen very few DYING trees. Some say we were in a long drought? yet my bushes never showed it, and 150 year old ohia's died.
Different ohia varieties are adapted to different conditions. The ones that do well in wet places don't do well in dry ones and vice versa. Also, those that live on lava flows naturally die after ~150-200 years, giving way to a different variety. Are the leaves of your trees fuzzy underneath or hairless? The fuzzy ones are the first to colonize lava flows and usually don't get very big, while the hairless ones come in afterward and eventually become the big forest trees.
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Digitalis. I have the big Ohia in OL and have had a hard time clearing the guava without killing the Ohia. I dont really know what to suggest. Alot of the trees that I was trying to clear, were also next to the driveway- so the the roots also may have been disturbed by the dozer. I have selectively used poison on the guava. IF you leave the guava, it will basically suffocate the Ohia eventually.
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quote:
Originally posted by Digitalis
If there are invasives growing right alongside the ohia (we have lots of strawberry guava and princess flower) what is the best approach- to uproot the nasty and risk messing with the ohia's root system, to cut down the invasive but leave the stump in place, or just leave it all together?
Cut them down and paint the stumps with Garlon (triclopyr) or Roundup. That will avoid getting it in the ground where it can affect the ohia and other plants. You will also need to apply it to the other end and stack the stems somewhere to let them die, because they may also resprout if it's wet enough.
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