here is what CRFG says:
"In M. integrifolia there are 3 buds in a vertical row in each of the three leaf axils of a node. When the stem is is topped, all three upper buds will grow straight up. Only one of them must be allowed to remain and to continue the main stem, the other two being clipped off to a stub of about 3/8 inch."

I didn't follow this advise & nothing horrible happened. My tree is about 20yrs old 25 feet high and has multiple trunks.

Here is a link that might be useful: growing macadamia

Thank you! How is the production of your multi trunked tree? Do you have any pictures of it?

Sorry for the delay. Had to wait till weekend to take pictures.
Yes, the tree produces more than enough(for us & family that is).But I'm way south in CA. Never heard of macadamia grown in WA. Do you know of any mature trees in your area or yours will be the first?

here are some pictures

Old nuts to the left, new - to the right

New nuts to the left, future nuts - to the center

Trunks

Thank you for the pics!

Of course mine will be container grown. I do not know of anyone else growing macadamia nuts in washington state although I'm sure there are. There are probably macadamia bonsais around here too.

I'm also growing cocoa, vanilla orchids, cinnamon, cloves, coffee, bananas, black peppper (piper nigrum) capers, and blue lilly pilly as well as plumeria, bird of paradise, and jacaranda.

I expected to be in zone 10 / 11 by now but al gore lied about global warming so we are still zone 8 (heading to zone 7 / 6) :-D

Well, you've got an impressive for WA collection going. Good job. Of course everything is flowering/fruiting for you, doesn't it? I'd love to try my hand at growing a vanilla vine. Would you like to trade a cutting? I can offer you one of the following
white sapote seedling,
cheriymoya seedling,
passion fruit vine cutting.

And, BTW, my good friend al gore didn't lie at all. Us, "small people", must learn to see through the doublespeak of our fuhrers, past and present. He never promised a global warming for everybody, did he? By moving from TN(zone 5 or 6) to the exclusive reservation for very rich near Santa Barbara(zone 10/11) he provided a great(one may even use the word "global") warming for himself personally. Remember, Nobel prizes are ALWAYS given to very smart people.

Last vanilla cutting I gave to my landlady (she gives me just as many plants) - have been debating whether to let my vines grow or take more cuttings. I bought both vanilla orchids about a year ago (variegated and the regular leaf)

What type of passion vine do you have? I have P. edulis, P. incarnata, and P. caerula already (all from seed) --- are yours rooted cuttings or un-rooted?

I mostly grow spices and a few others - and plants many people here have never heard of here (IE: Blue Lilly Pilly) or plants that are hardy (Citrus junos - Yuzu). I do love passion flowers though and if you have one I don't already have, I would consider a trade.