I was up at my dad's over the last few days. He's a bit poorly but took the time to show me around his new layout and in particular the trees he's just been making. Anyway his technique is new to me and the results looked superb so I thought I'd share it ... apologies if it's old hat.
In essence he uses the stalks from bunches of grapes to form the trunk and branches of the tree. Dries them first to make them hard then chops of the little knobbly bits on the end of the stalk and lo and behold there you go, all ready for flok or covering of your choice.
They looked really good, could see the very fine grain in the stalk I'm going to have a bash with them myself over the next few weeks, for anyone who hasn't tried using them, give it a go.