Trstenjak families are Croats and they are mostly from Mursko Sredisce area. In the past century, relatively most of Croatian residents bearing this family name were born in Cakovec and Zagreb.
Prevalence
About 730 people with faimily name Trstenjak live in Croatia today, in 310 households. There were 590 of them in the middle of the past century, and their number increased by 20 percent. They are located in almost all Croatian counties, in 30 cities and 84 other places, mostly in Zagreb (100), Cakovec (65), Belica in Cakovec area (40), Mursko Sredisce (30), and in Varazdin (25).
In the sources analysed in the project Acta Croatica so far, the name is mentioned over thirty times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.