Don't think so. The reason you are seeing "extra" trees is that there are only so many slots in your city where trees can grow (let's assume 10 for this example; not sure how many there actually are). So if 15 people plant trees for you, you'll see only 10. If you refresh or do certain actions to refresh the area surrounding your city, you will also see the remaining 5 trees. This is just an assumption, but I'm fairly certain that this is the case.

PS. This is true on desktop -- no idea on mobile.

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