Gardening - Type of weed
This is Glechoma hederacea, commonly known as ground ivy or creeping Charlie. Hand pulling or using an appropriate weeding tool are the primary means of mechanical control. This is a viable option at the beginning of an infestation and on young weeds.
For chemical control, spot-treat with a liquid, selective, post-emergent, broadleaf weed killer applied when weeds are actively growing. Look for a combination product with the following active ingredients:
2, 4-D, MCPP (mecoprop), Dicamba (be careful when using around tree and shrub roots) or Triclopyr.
Here is additional information on ground ivy and options for controlling it: