I want to do a tropical design cake, with palm tree, but I don't want to do fondant figure making and all that hassle. Does anyone have an idea of how to pipe the trunk of a palm tree so that it has the right texture for the look of it? Does this even make any sense?

I use the braided pretzels for the tree trunk and then pipe the top of the tree.

The same idea as above - take chocolate wafer stick

pipe leaves in it (or pipe leaves in RI, let it dry - then, give a dot in the wafer stick and stick the leaves inside)

if all else fails, i'll try one of those. it's occurred to me to try piping a line with like, tip 12, then using a tip 101 or similar to criss-cross back and forth over it with the thin end of the tip facing the top of the palm tree and slightly lifted. i'll try it and post whether or not it works.

Oh, I understood you wanted a standing up palm tree

To pipe palm tree "flat" on top of the cake, take round tip - I would go with smaller tip, about 10. Start on the bottom of your palm tree trunk, with heavy pressure, draw slightly curved line releasing the pressure. Make the texture with toothpick - simply draw few lines in the buttercream.
With small round tip draw the branches. Make leaves with the same tip as the branches.
Or with leaf tip /or parchment bag cut as V/ pipe leaves and with toothpick pull out points (as with holly leaf - http://www.wilton.com/technique/Holly-Leaf

What I described first comes from drawing - http://www.drawingcoach.com/palm-tree-drawing.html

Good luck with your cake!

the toothpick never occurred to me. i'll try both and see what works best for the look i want. thanks, majka