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June 2016. Attached are pictures of a dead 2-year-old grafted macadamia. They are from Samoa, and the sender has four varieties from Australia. Something is attacking the basal part of the stem. Does it look like Phytophthora disease like that common in avocado? If it is, does Phytophthora infection appear early as in this case?
Members said that it was hard to tell just from symptoms. Can someone do some isolations for you? Also, be helpful to peel back the bark and take photos of any staining inside. Look for tunnels also, which would indicate an insect. It would also be worth while scouting nearby tree trunks and looking for brackets of Ganoderma and Phellinus.