Calvin Payne was found in contempt last week at the High Court in Sheffield, following a Facebook post he wrote encouraging others to break the injunction.
In his latest judgment, Mr Justice Males ruled he also twice stepped inside the “safety zone” erected around some trees, which he was forbidden from entering.
It follows a long and bitter dispute between Sheffield City Council and protesters who have tried to stop the felling of hundreds of trees.
As a result the city has seen regular street protests and a series of arrests as contractors removed the roadside trees.
The judgment also referred to other incidents, which although did not constitute contempt, Mr Justice Males said demonstrated his “attitude”.
This included a comment he wrote on a Facebook post about people getting arrested, which said: “That’s a risk we’ll have to take. I no longer care. I’d rather do what’s right than be what the powers that be see as well-behaved and respectable.”
On Friday, an application to commit Green city councillor Alison Teal was dismissed.
Sentencing is due to take place on Friday..
The dispute has its origin in a 25-year £2.2 billion private finance initiative agreement the council signed with contractor Amey in 2009.
The contract includes a huge programme to resurface thousands of miles of Sheffield’s pothole-ridden road system and as part of this, Amey is tasked with maintaining 36,000 roadside trees.
The contractor and council say the trees being removed are diseased or dangerous and all are being replaced.
But protesters say many of the trees and their root systems are simply getting in the way of Amey’s resurfacing methods and the council has locked itself into a contract aimed as maximising a private firm’s profits.
A year ago two pensioners were arrested in Rustlings Road after an operation described by the then local MP and former deputy prime minister Nick Clegg as being more like a well-planned anti-terror raid than a morning of tree maintenance.
The council later apologised for the Rustlings Road operation.