5 Jan 2023

A Botanic Garden Tree Diary

Bruce Langridge

How should we monitor changes to our climate and to our trees?

Spreadsheets, data loggers, high-tech software. That’s one way.

But our Conservation Volunteers, made up largely of retirees who share a love of nature, have taken an alternative approach.

They’ve created a Tree Diary. Since the beginning of 2019, they’ve been meeting up every Tuesday and amongst of a host of other activities, they visit the 16 tree species they have chosen to monitor. Spread across the Botanic Garden and its Waun Las National Nature Reserve, they make a note of the formation of catkins, when the first leaves burst into life, flowering times and in autumn, when leaves fall. In between, they take note of insects, birds or mammals they find on the tree, fungi either on or tethered to the tree, lichen or general tree health.

Have a look through this 2019 diary.

You’ll see that it’s beautifully hand written by Marie Evans, the co-ordinator of the tree surveys. She’s arranged it in order of each of the trees they’ve surveyed, beginning with a mature beech tree in a wet pasture on Waun Las, a lime tree in the Arboretum and a goat willow covered in rare lichen, and ending with the copper beech and ash on the lawns next to Millennium Square. You’ll also come across the volunteers who make these observations, and the exquisite nature drawings of Frances Payne.

Fellow volunteer Gary Beard scanned the diary to allow others to leisurely look through each entry, whilst much of the photography came from the fancy cameras of John James and Peter Williams.

As 2022 comes to an end, the volunteers have now completed four years of observations, albeit with a slight Covid restricted interruption in 2020. In just the past 4 years, they’ve noted big differences in the dates of leaf bursts and falls, the decline of a very old sweet chestnut, the first-time appearance of deadly death cap fungi next to the silver birch, an explosion of acorns on the oaks, the growth of ivy up a horse chestnut and the fight for survival of the ash tree from a fungal attack.

These observations may not be scientifically rigorous but they present a fascinating picture of the slowly changing character of each tree which, like a fine wine, will grow in value as the years pass. Imagine looking at one of these trees in 50 years’ time and comparing what you see then to now.

All of the tree diaries will be securely kept in the library in the Garden’s Science Centre. We’ll be making similar short films of each diary in the new year.