How to make a basket
out of native vines
The first step is look for some vines, do this in the summer or fall when the vines are still alive and are of decent length. Really any vine will do and if you can't identify the species that’s fine. My advice is that you stay away from poison ivy. If you don't know what this looks like find out before you go vine hunting.
Personally, my favorite are grape vines. These are plentiful where I live in Pennsylvania. In fact there some across the street! Now to cut them, obviously you don't want to kill an entire plant as you or your friends might need more vines next year. Grapes are very generous with providing shoots, so this should be no problem even if you have trouble finding vines. Just cut off shoots close the base, I like long lengths but they can be difficult to work with especially if you are making a small basket. Take only what you need cause when the vines dry they are useless. It’s ok to take too little, you can always go back and get more vine.
Now you need to decide what size basket you will be making. The first step is to make a ring which will be the top of the basket. This first step is a lot like making a Christmas wreath. You'll bend the vine into a circle near one end. Then with the long end you'll weave it in and out of the circle while pulling tight until the ring stays in shape of its own accord.
Next, you'll need to make the frame for the actual basket part. This is where you have to decide exactly how much volume your basket will have. For this you'll be making two U's which come out from the ring and intersect with each other in the form of a cross. This is hard to describe perfectly in just words, but it'll become clear as you do it. Take that long length of vine which is sticking out from your ring and bend it perpendicular to the ring. Then, making a U shape, bend the other end back down into the ring on the opposite side. Then weave this end securely into the ring.
You'll do this once more, and this second time will make your first U stand up more securely. You'll want your second U to intersect the first one so that the bottom of the emerging basket looks like a cross. You'll make the U the same way as described above.
Now you should be left with something that looks like the frame for a basket. Get some string, or if you're feeling adventurous you can use something pliable and green to tie the cross at the bottom of the basket together. This is for stability.
Now you just need to fill in those gapping holes and you can put stuff in it! The rest of the process is pretty much open ended; just weave vines amongst the structure in any chaotic or ordered fashion that suits you. You can have as many or few gaps as you like depending on what you plan on storing in it.
And there you have it!