GREETINGS everyone. Last week I talked about Dr. Lynn Raulerson, the director of the UOG Herbarium and what a difference she made to the island. This week, I was delving into the plant file and discovered why her job is really important. So follow me on a little journey into the wonderful world of plants.

We haven’t talked much recently about global warming and climate change either, but it turns out that researchers in Britain have been learning about long-term climate change by studying plants picked up to 150 years ago by Victorian collectors and held by the million in herbarium collections across the world.

The study of climate-driven events like trees growing new leaves in temperate zone spring or when plants flower is called phenology, and the lack of long-term data has hindered scientists' understanding of how plants respond to climate change. But new research by a team of British ecologists shows that plants pressed up to 150 years ago tell the same story about warmer springs causing earlier flowering as recent field-based observations of flowering times.

The team examined 77 specimens of the early spider orchid (Ophrys sphegodes) collected between 1848 and 1958 and held in the herbarium at the Royal Botanic Gardens in Kew. Because each specimen contains details of when and where it was picked, the researchers could use weather records to determine how changing spring temperatures affected the orchids' flowering.

They then compared these data with field observations of peak flowering of the same orchid species in the Castle Hill National Nature Reserve, East Sussex from 1975 to 2006, and found that the response of flowering time to temperature was identical both in herbarium specimens and field data. In both the pressed plants and the field observations, the orchid flowered six days earlier for every 1-degree increase in mean spring temperature.

Direct proof

The results are first direct proof that pressed plants in herbarium collections can be used to study relationships between phenology and climate change when field-based data are not available, as is almost always the case.

The study opens up important new uses for the 2.5 billion plant and animal specimens held in natural history collections in museums and herbaria. Some specimens date back to the time of Linnaeus (who devised our system of naming plants and animals) 250 years ago.

The scientists say there’s an enormous wealth of untapped information locked within our museums and herbaria that can contribute to our ability to predict the effects of future climate change on many plant species, and that it may be possible to extend similar principles to museum collections of insects and animals.

One wonders what stories the plants in the UOG Herbarium will tell in 100 years? Well, here’s one it can tell right now.

Some of the plants in the UOG Herbarium were collected on the Palau island of Peleliu. Peleliu is the site of Bloody Nose Ridge and it was the scene of some of the fiercest battles of World War II. The Americans used flame throwers to dislodge the Japanese and by the end of the battle, the entire island was a charred and smoking ruin with virtually no vegetation.

Dr. Raymond Fosberg, a well-known botanist from the Smithsonian Institute, did a plant survey on Peleliu in the early 1950s. He found about 50 species of plants, most of them American weeds that came in on the vehicles that were brought to the island.

In the early 1990s, some 40 years later, Dr. Raulerson did a series of plant surveys on Peleliu and I was honored to accompany her on the trips. We discovered more than 200 species of plants on the island and virtually all of them were the native species that should be there. We also found a 60-foot-tall tree near the American headquarters building that was not there when the building was photographed in the early ‘50s. An amazing story about the regenerative power of tropical plants and the importance of herbariums.