Jute string refers to a thin, strong cord or rope made from the plant called jute. It is commonly used for tying or binding things together. Full definition
6 Table Wedding Centrepiece Jars with Jute String Bow Detail Ideal for flowers or Candles Rustic / Traditional Style (etsy.com)
If you want the little curly twine like I added to mine above, you'll just wrap a piece of jute string around a pencil and paint it with Mod Podge. (therusticpig.com)
For the top of the chalkboard, I dry - brush painted two metal grates that I had found at an antique shop years ago, then tied jute string from one end of the other and clipped pictures of our friends onto it, wash - line style. (skiesofparchment.com)