You can get them from Cornimer on Harv’s plaza(fall only)

Also, don't be afraid of the aggressive multi-shake. Most trees will give up four of five things, granted I have a ridiculous number of branches, but it's also the best way of getting acorns and pine cones.

Those of you running from wasps: hold your net, stand in front of the trees, and shake. It will turn you to the wasp when it falls, and you can tap A and catch the wasp. Easy peasy.

You don't need to outrun the wasps - always hold a net when you're shaking, then you can catch the wasps.

Tip: When shaking trees and wasps start to come after you, run to your museum. They will not be able to attack you once you’re in

N. Hemisphere. Sept 1: can confirm acorns from fruit (Peach) trees, tested twice. Lots of shaking.

Northern hemisphere, September 1st. I found a pine cone and 5 wasp nests this was a bad idea but I am still trying.

Northern hemisphere, September 1st. Now 4 wasp nests. I am nearly out of medicine but I have found that if you go in water the wasps leave you alone.

Northern hemisphere, September 1st. The cedar trees only give you tree branches and wasp nests. I tried to get a pine cone from some trees, all I got was 11 tree branches and I found 3 wasp nests so far.

You can get acorns from fruit trees. I tried today (1st Sept) northern hemisphere. After harvesting fruit repeatedly shook trees to get multiple branches and usually an acorn. Keep shaking the tree after the first branch or item falls out