When you place a groundcover hatch, an extra boundary appears in your planting area, which contains extra arcs or loops.
Here's an example:
Check your Planting Preferences. You likely have the Ground Covers Exclude Shrubs option checked, which excludes shrubs from all groundcover hatches automatically.
In the process of excluding shrubs from groundcovers, the software has to determine whether or not each groundcover boundary contains shrubs. This requires it to make a copy of the bounding polyline and then de-curve that copy.
The issue you're experiencing occurs when this de-curving operation fails for some reason, leaving the small loops you see within your groundcover boundaries.
You can safely delete any polylines that are causing this issue.
You may also consider unchecking the Ground Covers Exclude Shrubs option in the Planting Preferences.
That way, you'll have a little more control of when that code fires.
You can use our Exclude Shrubs tool to exclude shrubs from groundcovers manually.
We will also certainly look into improving the de-curving capability of this feature.