No, since you told him part of the hedge was on your property and forbade him to cut your 1/2 of the hedge, he committed willful & wanton trespass to chattels/property. You may sue him in civil court for the damage to your hedge, and can sue your neighbor because he was neighbor's agent. To win, you'll need to hire a surveyor to establish the property line and measure how much of the hedge was on your side.
The case depends on whether reaching one's shears over a property line to cut a hedge constitutes 'entering land.' (As a comparison, reaching a hand or crowbar into someone's house is 'entry' sufficent for a burglary conviction.)
You can also file a criminal complaint against the trimmer.
Keep in mind that suing your neighbor will destroy any chance you have of a good relationship.
810.09 Trespass on property other than structure or conveyance.--
(1)(a) A person who, without being authorized, licensed, or invited, willfully enters upon or remains in any property other than a structure or conveyance:
1. As to which notice against entering or remaining is given, either by actual communication to the offender or by posting, fencing, or cultivation as described in s. 810.011; or
2. If the property is the unenclosed curtilage of a dwelling and the offender enters or remains with the intent to commit an offense thereon, other than the offense of trespass,
commits the offense of trespass on property other than a structure or conveyance.
(b) As used in this section, the term "unenclosed curtilage" means the unenclosed land or grounds, and any outbuildings, that are directly and intimately adjacent to and connected with the dwelling and necessary, convenient, and habitually used in connection with that dwelling.
(2)(a) Except as provided in this subsection, trespass on property other than a structure or conveyance is a misdemeanor of the first degree, punishable as provided in s. 775.082 or s. 775.083.
(b) If the offender defies an order to leave, personally communicated to the offender by the owner of the premises or by an authorized person, or if the offender willfully opens any door, fence, or gate or does any act that exposes animals, crops, or other property to waste, destruction, or freedom; unlawfully dumps litter on property; or trespasses on property other than a structure or conveyance, the offender commits a misdemeanor of the first degree, punishable as provided in s. 775.082 or s. 775.083.
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This is not legal advice and you are not my client. Double check everything with your own attorney and your state's laws.