The ivy is gort in ogham.
Don't worry about English ivy choking anything - it doesn't. In fact we have a lot around here (central England) on old individual oak trees that is protecting them from getting their bark scorched in the sun. It gives them a much longer life. If you look at an established wood - you'll see that the eves of the wood are completely green and the trunks of the trees are only bare inside the wood. Bark can get sunburn, just like humans! Isolated trees grow a wide canopy to protect themselves, and very often allow ivy to grow up the trunk to protect them.
More information to come.
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