13 November 2015

Friday Five: Seeds

The largest organism on Earth, the General Sherman (Sequoiadendron giganteum) germinated from a seed weighing just a six-thousandth of a gram.

So far, the earliest seed plants that have been found in the fossil record are from the Devonian period, showing that seed plants have been around for at least 360 million years. The plants were gymnosperms, which include conifers and cycads, as well as the living fossil ginkgo biloba.

There are about 600 different species of fungi that are known to infect seeds and use them to propagate themselves. Some can be beneficial, or at least benign to the plant, however some can cause disease, such as bunt in wheat. These fungi destroy the flowers and then spread by spores.

The coco de mer is the biggest largest seed in the world. It was originally collected in the Maldives, which is why it was given the epithet of maldivica, however its' true home was eventually found to be the Seychelles. It can grow to 18 kg / 40 lbs in weight and around 30 cm / 12 in long.
The large size allows the seed to power the growth of the plant so efficiently that it can grow 10 meters in height within a few years.

The largest wingspan of any seed is held by the Brazilian zebra wood tree (Centrolobium robustum). These seeds are protected by spines and have a wing up to 30 cm long!

Here's David Attenborough talking about the coco de mer seeds:

Silvertown, Jonathan. An Orchard Invisible: A Natural History of Seeds. Reprint edition. Chicago; London: University of Chicago Press, 2010.

31 October 2015

Trunk of the Month: October 2015: Acer platanoides

The Norway maple has a large native distribution, taking in large tracts of Europe and western Asia. It can grow above the arctic circle, such as in Tromsø, Norway. It's even used in Alaska, since introduction there in the 18th century, for shade and street planting. A common replacement for the Norway maple in formal plantings (as the Norway maple can be invasive) is the London plane, which is interesting because the 'platanoides' epithet refers to the leaves resembling the plane tree. Indeed, plane-leaved maple is another common name for this tree.

There doesn't seem to be a great use for building material as it's considered non-durable to perishable. However, it seems to be used for musical instruments, along with flooring and furniture. It doesn't seem to be used for syrup either, due to a lower concentration of sugar in its sap.

The tree is often planted for ornamental reasons, primarily for the enjoyment of the colour change in the leaves. The Norway maple has many cultivars that concentrate on the colours of the leaves, or the shape. 'Crimson King' has been given the coveted RHS Award of Garden Merit.

Flora Britannica advices that this species can self-seed throughout lowland Britain in scrub, hedgerows, and woodland. So, it's one to look out for when you're out and about.

The rough grooves that criss-cross the trunk are what I like about this tree. The grooves provide a great touch sensation, as well as much needed places for lichen and moss to grow.

Mabey, Richard. Flora Britannica. 1st edition. London: Chatto & Windus / Sinclair Stevenson, 1996.
Acer platanoides - Wikipedia, the free encyclopedia. 2015. Acer platanoides - Wikipedia, the free encyclopedia. [ONLINE] Available at: https://en.wikipedia.org/wiki/Acer_platanoides#Cultivation_and_uses. [Accessed 03 November 2015].

05 October 2015

Book Review: Seven Flowers by Jennifer Potter

This comprehensive book looks at seven different flowers and how they shaped our world. The author uses these flowers to explore how we've used these flowers throughout history and can now look back and use them to tell us something about where we come from and who we are.

The book covers the lotus, lily, sunflower, opium poppy, rose, tulip, and orchid.

As well as telling us when these flowers made a big impact on the history of particular cultures, it also tells us when they didn't - even when we'd have expected them to. For instance, the author explains that in Incan and Mayan mythology and ritual, the sunflower plays no role whatsoever - yet we go on to read tha since Europeans took seed from their lands to Europe, the sunflower began to have a large role in culture and was very popular for a time.

The book also looks at the economic uses of the plants, a prime example being that of the oil from the sunflower seed - developed for a higher oil percentage in Russia and even higher when the American's got their hands on it.

Of course the opium poppy was used as an excuse for war; with the British Empire fighting China for the express purposes of continuing the trade of opium to the Chinese population.

This book has a great deal of information in it and, for me, required a lot of concentration. I felt like the information in each flower chapter could have been fleshed out and made into a book of its' own. Instead it read like a bullet point list of facts and sometimes this negatively impacted the flow. However, this is a really good book and there's lots to get out of it. Even if you don't have a specific interest in any of these flowers, you will gain a greater understanding of how flowers have helped humanity survive and flourish.