2021-09-19 Game Management Advisory Commission Minutes

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forward. One of the things that really struck us with this is often the largest and healthiest trees in the whole stand were getting killed and other diseases, you know, they tend to take out the weaker trees – the ones that area shaded out and the disease will take ‘em out. This is a really virulent disease and it will take out the biggest and healthiest trees in the stand. So it’s a really virulent pathogen. So over the – we – I’m not the one who figured out what the disease was – it’s pathologists and both by the morphology and DNA analysis of it – so it was just named and discovered in 2014. By 2020 we had detections across the Island – so pretty much every district of the Island has at least some detections – so this is a map of the laboratory detections of the disease across the Island so it is worse in some areas than others. You’ll notice in some places it follows the road – like up Saddle Road. We’re not taking samples from the middle of the forest in Hakalau, no – or places like that or really deep in the Kau forest but there are some detections all around the Island. Now one of the things that we know about this pathogen is it’s known as a wound pathogen. The fungus can’t go through bark – bark is a really good protection against disease – it’s just like you’ll get an infection if you get a cut and go in the water but not if you don’t have a cut. The pathogen in the oak wilt pathogen – they found it’s a disease of urban trees – so when they prune the trees the trees get the disease. One of the things that we’ve seen here is that when trees get injured they tend to get the disease. So this is a tree down in Kau, it’s growing on the lava and people passing by notice why are those trees there turning brown – they went out and looked at it – animals had been killing the bark – I’m not sure if they were goats or sheep but there were both goats and sheep in the area and so when you look at this – this is the fungus growing on the peeled bark – so the trees probably wouldn’t have gotten the disease but the animals are peeling the bark and injuring them so, um, now there are a lot of ways that trees can get an injury – this disease took off in Puna that’s a little different question – probably the fungus was brought in with plants with the nursery trade – just like a lot things started in Puna in the trade it was brought in and it jumped to ohia – we’re not really sure – we may never really know. But what happened in Puna in 2014 – we had a hurricane hit the Island so, you know, trees were damaged by the hurricane across – especially in that area and in the following years we had a huge outbreak of disease – so wind is nothing we can do anything about but what we are finding is that in a number of sites – the same forest but it’s a property boundary and the two sides are managed differently – we see a lot more disease on one side than the other. So there’s a little complicated maps – this is kind of the heart of my presentation so I’m gonna spend a few minutes on this – this is Kahuku – so this is the Hawai’i Volcanoes National Park, Kahuku section – so it was the old Kahuku Ranch – you see the paddocks there – the pink line shows the outline of the helicopter flight – so this was a map and a survey done by my colleague Ryan Perroy in Hilo and what he’s done is mounted cameras on a helicopter to map trees that show symptoms from the air. And as I mentioned, the symptoms of the Rapid Ohia Death are the whole crown of the tree turns brown. In this site – the sort of red dots are trees that have very sure – high confidence is Rapid Ohia Death – the yellow ones are medium confidence – when we do on the ground sampling those numbers and I forget off the top of my head but high confidence there was 98% or something, medium confidence 16