Four days with RBG Kew’s Millennium Seed Bank (MSB) collecting for the UK National Tree Seed Project (UKNTSP) by Ellen Baker
With climate change set to alter environmental conditions such as temperature and rainfall, as well as the distribution of pests and disease, UK trees and woodlands will be facing big challenges to their survival in the coming years. If, through seed collection, we can identify natural populations capable of healthy growth in these conditions, then we can secure the future of many of our wild trees. This year I got the opportunity to volunteer for the UKNTSP; an initiative set up and run by RBG Kew, funded by the Postcode Lottery. The aim of the scheme is to collect seeds from wild trees in the UK for storage at the MSB; these seeds will then be used for research including germination tests to understand their individual adaptations. On our collecting trip we would be targeting bird cherry (Prunus padus) and wild cherry (Prunus avium) populations.
Challenge one on collecting trips is always finding the target species. Fortunately, most of the work had been done for us and previous scouting trips had identified suitable natural populations and preliminary surveys marked out the target trees. Unfortunately, this does not always translate into reliable maps, as proved when on our first day we spent over an hour searching the same few meters of woodland for one tree. Even if the correct species can be found, there is no guarantee that it will be fruiting; when our target populations on Lower Lough Erne proved not to be fruiting it was the advice of our local RSPB guides that led us to an unrecorded, but very fruitful population.
View across Lower Lough Erne. Having found only immature fruits on the first island we landed on, our RSPB guides kindly took us over to another where we found a whole grove of wild cherry (Prunus avium).
If a suitable tree can be found the next challenge is collecting the fruit. The ideal aim is to have 10,000 seeds from 15 trees however in reality this can be tricky to achieve; for wild cherry which only has a few fruits per bunch it can mean lots of cutting for little reward. The trees we collected from were all very tall meaning we had to use pole pruners to collect the fruits.
Fruits collected from a wild Prunus padus, Bird cherry, tree on the National Trust Crom Estate. Labelling the tree helps next year’s collectors find the individual. The flesh and stalks of the berries will be removed at the MSB leaving a collection of clean, dry seeds for germination tests.
The collected seeds are then shipped back to the MSB, where they are cleaned, dried and tested for viability. Trips like this help to build up a supply of seeds from different populations of the same species, allowing science to preserve a snapshot of its genetic diversity. This increases the probability that some individuals may have adaptations which will the species survive in changing conditions.
Green elf cup fungus (Chlorciboria) growing on a moss covered log in the woods of Crom estate. This little ascomycete will actually stain the inside of the wood green; a trait that used to be prized by furniture makers for creating coloured inlays.
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