A smaller version of last years garden stakes. I've seen claims PLA is biodegradable but it's held up with little degradation for a year so far.

Printed on a Prusa I3 Mk3. I used PrusaSlicer and added a filament change at 4mm from the print bed. The bottom layer using a blue filament, and the top layer using a yellow filament. Of course any colors with good contrast will work fine.

No supports are necessary since these print flat.

Modeled in Blender. The blender source file is included.

To create your own I recommend duplicating the basic unmodified stake shape. Duplicate an existing text object and edit the text. Add a carriage return between each letter so the text moves top to bottom instead of left to right. I've had no end of trouble with the boolean modifier so I don't use it for print projects. You can use the “Knife project” command with the text object to cut the top surface of the stake object. Extrude the faces that create the lettering in the Z axis so they extend above the 4mm mark. The second layer of filament is not 100% opaque so extrude far enough to get a decent number of layers. If the second layer is too thin the contrast will be low and the lettering will not be as readable.

Select the modified stake object and export it as an STL. Make sure to check “Selected only” if you don't want everything in the exported. The blender file units were left as “meters” but since STL formats don't include units of measure it works fine as an STL with any slicer.