I don’t know why I didn’t notice it before, but the shadows cast by the nest onto the front of the tabletop weren’t ideal.
As you can see above, the five shadows are almost exactly alike in size, value and direction. I usually try to vary the space between objects. I also try to avoid repeating the same shapes without introducing some variety. Below, I painted over the shadow on the far left, and re-painted it in further to the left, where it actually should have been. I painted it much lighter than it had been, so as not to draw as much attention. I shortened the next shadow on the left, so that it didn’t reach down to the edge of the table top. The other shadows remained much the same, except that I lightened them. I added some very fine strands of grass, visible against the dark area under the tabletop.
I’m much happier with the dried grasses hanging over the edge and the shadows they cast now. I’ll need to repaint another layer over the painted-over shadows when they dry to get complete coverage. I’ll also soften the edges of the shadows.