The following blog was written by Chris Knowles a digitiser in the Herbarium.
Since 2021 we have increased our digitisation capacity reaching 1 million specimens imaged in August 2024. Each digitiser is assigned a family of plants to work through. This series of blogs will spotlight the families that have been completed by a member of the team.
The willow family, or Salicaceae, is a group of plants that is very diverse, but does includes some trees that are very familiar in temperate countries like the UK. The main groups (genera) are willows (Salix) and poplars (Populus), which includes aspens and cottonwoods. Often, these trees favour wetter soils and are commonly found near rivers and lakes, the typical places to find large weeping willows or in the North of Scotland the fluttering leaves of an aspen tree.
In bankside habitats, these trees can be very important in helping to prevent soil erosion while also provide shelter and food for wildlife.
Although many of us can recognise a riverside willow tree with its drooping branches providing a shady place for a picnic, less well known are species like the woolly willow (Salix lanata) that grow on our highest peaks where they cling to the rocky terrain and can be just a few centimetres tall, and rarely over a metre high.
For many centuries, the bark of willow trees has been used to reduce pain and fevers. It contains a natural chemical called salicin, and was the precursor to modern aspirin. Aspens on the other hand are a tree with many mythological links in Europe, and both crowns and wands made of aspen have been found in ancient burial sites from West Asia to the British Isles.
Our Collections
There were 7,306 specimens already online before we began the mass digitisation project, and there are now 15,467. We hold 237 type specimens for species in this family. You can view our collections here.
Top 5 Regions
| No. of Specimens | Herbarium Filing Region |
| 4,271 | Britain and Ireland |
| 2,558 | Europe (excluding Britain and Ireland) |
| 1,803 | North America |
| 1,351 | Inner China, Korea & Taiwan |
| 1,228 | Cultivated |
Top 5 Genera
| No. of Specimens | Genus |
| 12,097 | Salix |
| 1,202 | Populus |
| 877 | Casearia |
| 340 | Homalium |
| 243 | Xylosma |
The RBGE herbarium collection of Willows (Salix) is representative of the global distribution of these trees, with specimens collected from countries across the temperate region of the northern hemisphere.
