Great photo, thanks for sharing.
I'm going to say 20's. I met a 2nd cousin who had a HUGE box of family photos for our shared family. MOST of them were from the 20's, happy faces, they looked well fed, dressed nicely. And then the depression. The photos just stop. Every year or two, a family group photo, but few individual portraits, no family snapshots, no pics out in the garden. Who could afford the Kodak development when no one had a job. I also noticed that the smiles seemed not as bright, they often looked tired like they were overworked or underfed. Looking at the 20's pics vs. the 30's pics was like night and day.
This doesn't look like a 30's pic to me.