Your Japanese maple has aphids, aphid mummies and ants.  Leave it alone and the predatory insects will take care of them.  The aphid mummy is evidence of this.  If you do not like aphids, you can squirt them off with a strong stream of water.  The ants are collecting honeydew that is generated when the maple is attacked by the aphids.  Aphids and their control are discussed at the following link.   https://extension.umd.edu/hgic/aphids-trees-and-shrubs   Having aphids early in the spring is very common, since the aphids tend to come out first and then the predatory insects emerge.  vw