David Bennett

Snowdrops (Galanthus) are a member of the Amaryllis plant family (Amaryllidacede), which also includes daffodils (Narcissus), Agapanthus, onions and chives (Allium).

I photographed these snowdrops at the Botanic Gardens in Cambridge. To get the exposure right so that the snowdrops weren’t blown out, I set the exposure compensation to minus one stop, and it seems to have worked.

Around a couple of the beds – and there were thousands of snowdrops in bloom at the Botanic Garden when I photographed these – are explanations and stories about snowdrops. One notice mentions that the stories are taken from A Monograph of Cultivated Galanthus (published by Bishop, Davis & Grimshaw in 2001). And the rest of this post is taken from highlights in the display notices, including how snowdrops defeat what icy weather throws at them.

In cold spells you will often see snowdrops collapse to the ground, only to resurrect themselves once the temperature rises.

Plant tissue is often damaged or killed by ice crystals forming in the cells during freezing. However, many plants, including snowdrops, have ‘anti-freeze’ proteins that help inhibit ice crystals forming and limit their growth, protecting the plant cells from damage.

Snowdrop leaves have specially hardened tips to help them break through frozen soil. These are essential qualities for plants that grow and flower at the end of winter. The outer segments of snowdrops move In response to changes in temperature. When air temperatures are above 10°C, pollinating insects such as bees are likely to be flying, and the petals move upwards and outwards, opening the flower for them.

The alkaloid Galantamine, used to treat Alzheimer’s disease, was first isolated from the snowdrop Galanthus woronowii. Galantamine is also found in other members of the Amaryllis plant family (Amaryllidacede), such as Narcissus and Leucojum. Today, Galantamine is mainly produced from plants: chemical synthesis is possible, but it is difficult and expensive.

If it were a blackbird like nearly all other blackbirds, then it would be all black, with a yellow beak. It is leucistic, which means an animal that has whitish fur, plumage, or skin due to a lack of pigment. Its shape and its beak says that it is a blackbird, but it is about ten percent bigger than a blackbird – unless the white areas are throwing of my sense of size. The last time I saw and photographed a leucistic blackbird – not far from here and a smaller bird – I wrote the following:

it is said that the reduction of pigment in leucistic birds causes their feathers to weaken and be more prone to wear. Leucistic birds are usually more conspicuous, which puts them more at risk from predators. There is also evidence that leucistic birds might be less acceptable to potential mates.

Well, yes and no. Being an hereditary deficiency, if the problem were that serious you would have thought that leucistic birds would have died out with no one to carry the defective genes.

A sign by the Giant Redwood (Sequoiadendron giganteum) in CUBG contains the following:

Carbon Offsetting
How many of my international flights could this tree offset?

CUBG has over 1,600 trees in its collection, with this being the largest.

This old Giant Redwood (Sequoiadendron giganteum), planted in the mid 1800s, locks a lot of carbon away in its wood. The amount of above ground carbon stored in a tree is a function of its wood density, height and stem diameter. Each year that a tree grows, it locks away more carbon into its wood. Although we mostly think of trees as carbon sinks, many become a carbon source in the later stages of their life due to decay. This 32 m giant redwood tree has a diameter of 190 cm and a wood density of 0.51 grams per cubic cm. Its above ground biomass has been calculated at 29 tons. It therefore stores 13.6 tons of above ground carbon.

This is equivalent to 49.9 tons of CO – that’s the same amount of CO, emitted by 8 people taking one return flight from London to Sydney in economy class.

It has taken this tree over 150 years to grow to this size and most don’t ever get this big!

It’s plain to see that offsetting flights by simply planting trees is not a sustainable solution to the problem. Nevertheless, tree planting is still beneficial, not only because of the additional CO, taken up by each new tree planted, but also for the biodiversity they are able to support. A single oak tree supports over 284 different insect species.”

Comment

Yes, we must reduce emissions, not least because along with CO and CO2 we are pumping out pollutants that are damaging everyone and everything they touch. But perhaps planting trees is more beneficial than the notice suggests. How about planting one hundred million trees? Eden Projects alone has planted over eight hundred million trees. And they are by no means the only charity planting trees worldwide. That scale of planting changes weather patterns, increases rainfall, stabilises the land. Look at the strip of forest either side of the Panama Canal for the effect of forests on climate.