Hi guys!
This is a map of an Austro-Hungarian chateau (pink building on the left) from the mid 19th century. I'm wondering what kind of plant could the fuzzy circles around it be? They don't appear on the map legend. My guess is that it's some sort of hedge, but it looks very odd and it's pretty big (the length of the chateau is roughly 45 meters, so they are at least 15 meters in diameter).
I know this forum might be the wrong place to ask about 19th century ornamental plants, but I don't know who else to ask :)

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Any guesses?