Looks a little bit like liquid amber. Was a tree removed from the area? New shoots can pop up from roots left in the ground.

Plus liquidambars do seed around.

Liquidambar was my first thought, but when I compare I find the leaves in images are much more pointed than these. Unless someone else can figure this out, I might have to go with that.

Some kind of fig maybe?

Fig tree - now considered invasive in California (I think.). I have a volunteer growing in my front yard - thought I was lucky - until I started noticing them every where.

It looks like fig to me also. I get them all the time here. The stem a definitely fig-like. Mulberry has a brown, woody stem even from a young age like this. Figs have a green, succulent-like stem that becomes woody with age. I would rule out liquidambar also because liquidambar has glossy leaves that are pointed, not rounded like these.

either liquid amber or fig. Seeing a growing tip might be good if you can get.

Liquid amber do sprout from the roots.