Last week was National Tree Week. The UK has celebrated National Tree Week as the start of the tree planting season since 1975. It is the UK’s largest annual tree celebration. We took to Twitter to ask for your most fascinating tree facts. Here are some of our favourites.

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North American fagaceae retain their leaves longer because there was not enough selection pressure to do otherwise and it is a remnant of the ancestral types as the species colonized further North after the last ice age

Stephen Murphy

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That some trees are physiologically speaking colonies of independent modules – this supports tree die-back under harsh conditions (rather than full mortality) as well as different timing in turning of leaf colours in the fall

Rob Salguero-Gómez

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Ginkgo biloba (Maidenhair) trees drop their leaves in one day – varying among locations (and microclimate and genotype?), but it’s getting later each year with climate change.

David Gibson

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Trees talk to each other! When one tree gets munched on by a herbivore, it sends signals out like pheromones to warn other trees to activate their defence mechanisms incase they get munched on too! Those trees make themselves taste nasty before the herbivores get to them!

Holz1

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Thank you to everyone who contributed their favourite fascinating tree facts. You can find the full thread on Twitter.