As an Amazon Associate we earn from qualifying purchases. Product prices and availability are accurate as of the date/time indicated and are subject to change.
You can't use the third-person plural pronoun with an antecedant of 'tree,' which is what you have in the example.
You have to rewrite it with a plural antecedant or with singular pronoun.
There would be many ways to do that, but choosing the best rewrite is not possible without the context of the story.
All on can really say is that example provided is incorrect. There are many ways to fix it.