Most Disease-Resistant Macadamia?

[Fiddler]

I had a Beaumont macadamia that was flourishing in the ground for three years, then suddenly developed some kind of fungal disease and died within a week. My other two macadamia trees (an Arkan Papershell and a Dana White) seem unaffected. Should I chance another Beaumont, or go with another variety?

[achetadomestica]

It would be nice to know what happened to your Beaumont
I have heard the best things as far as productivity and overall health and vigor
in Florida about the Beaumont. It is also self pollinating which should not be an issue
if you have 3.  I would get another Beaumont and plant it in a different area.
I also would consider getting other Hawaiin or Australian types if you have the
room. I have 4 types and know they can be a very challenging tree for Florida.

[Jagmanjoe]

Just a little side note here since I see you seem to be in Central Florida.  There is a commercial macadamia orchard in the Plant City area on the north side of Rt. 60 just east of Rt. 39.  I believe it is called Brackins.  Some people with commercial businesses like this often like to talk about their business and may be able to provide a little insight for you.

[Fiddler]

Thanks for the replies. I'm in Venice, south of Sarasota. The Beaumont suddenly started showing brown leaves, and every day there were more of them. In a week the entire tree was covered with them, not a green leaf to be found! I read somewhere it was a fungus infection and highly contagious to the other trees, so I pulled it out and burned it. The shame of it is that it was a very productive, fast-growing tree. Broke my heart!

[Galatians522]

Sounds like ambrosia beetle damage. They drill into the tree and cultivate a fungus in the cambium thay their larvae eat. It is called Laurel Wilt in Avocado. I had not heard of it in Macadamia before, but apparently it is called Quick Tree Decline when they infect Macadamia. I don't know of any resistent varieties, but thinner barked varieties will probably be more susceptible.

[Tropheus76]

I have both macs and avocados, any way to prevent ambrosia beetles from attacking?

[Galatians522]

I have both macs and avocados, any way to prevent ambrosia beetles from attacking?

Keeping the tree healthy helps, but it is not fool proof. The beetle is especially attracted to trees that are stressed.

[Jack, Nipomo]

I wonder if you recently fertilized the macadamia.  Very extensive Proteoid roots are extremely efficient in pulling nutrients from soil and it is therefore easy to overfertilize a macadamia.

[Galatians522]

I have both macs and avocados, any way to prevent ambrosia beetles from attacking?

Keeping the tree healthy helps, but it is not fool proof. The beetle is especially attracted to trees that are stressed.

Here is a good and fairly concise article that talks about ambrosia beetle control.

https://www.google.com/url?sa=t&source=web&rct=j&url=http://ecoipm.org/wp-content/uploads/beetles_an_may13.pdf&ved=2ahUKEwiA0PK2r_LuAhVOo1kKHQi5CPUQFjABegQIAhAF&usg=AOvVaw00jVPrRFu7VHuBnP_Fe48m