Every summer there is aarranged a treeboat festival in the city of Halden. The city is placed at the border to Sweden in the most south-east part of Norway.
Yes they are all made of wood. We have some boatyards that still build these boats both in Norway and Sweden. They are popular and very expencive. When I was young everyone owned one, but these days they are becoming quite rare.
The hand held rudder is quite common on many of these boats. They are often combined sail- and motorboats. At home vi had several boats when I was young and the typical leasure/fishing boat was a 23" treboat with a hand held rudder at the stern. Bigger boats also had the stern rudder, but they were operated by chain or wire.