Enter BRUTUS in his orchard. This stage direction probably does not indicate the presence a tree or any other stage property. It's necessary that we know that Brutus, waiting for Cassius and the Ides of March, is just outside of his house in the dark. But that can be conveyed by his calling for his servant and looking up to the sky as he says, "I cannot, by the progress of the stars, / Give guess how near to day."