Very thin stringy weed climbing from one plant to another. It forms many small 1 cm balls of smaller balls (green) on stems of plants as it grows and attaches from one to another. It lived through a cold Jerusalem winter even though it died back. Would a picture be better?
A picture would help, but if you contact the Jerusalem Botanical Gardens, they will be able to answer your question straight away, and probably give you a wealth of other information besides.