Meanwood Valley bioblitz's Journal

Journal archives for January 2023

05 January, 2023

Species Of The Week Number 15: Hazel

It is pretty grim outside this week but the earliest signs of a new year's growth can be seen in tree buds, and in particular the catkins adorning local Hazel trees.

Hazel is native to the UK has long been coppiced. This involves cutting down new branches or 'wands' which, as they are so flexible, have a variety of uses including making hurdles for fencing as well as furniture and bean poles. You can actually buy hazel wands locally from The coppicing process encourages new growth meaning it is a very sustainable resource. Coppiced Hazel trees can live for hundreds of years

The catkins themselves are the male flowers of Hazel, and are accompanied on the same tree (meaning they are monoecious) by tiny bud-like female flowers, with red extensions or styles. Trees are pollinated by the wind not insects. The pollen isn't sticky so it doesn't stick to insect bodies.

Hazel nuts or cobs are eaten by birds and squirrels so you have to be quick when they appear. The nuts used to be harvested commercially in the UK, but this has declined with now only a few cultivated varieties being collected down in Kent.

In addition Hazel leaves provide food for the caterpillars of moths, including the large emerald, small white wave, barred umber and nut-tree tussock. Hopefully we can find some of them in the coming months and add them to the growing number of Meanwood Valley species (which is currently standing at 246)

Posted on 05 January, 2023 17:18 by clunym clunym | 0 comments | Leave a comment

11 January, 2023

Species Of The Week Number 16: Alder

Following on from Hazel in Week 15, the other common catkin to be seen at this time of year is on Alder - the tree of river banks and pond edges. We have quite a few along Meanwood Beck although I'm not sure if any still grow on the eponymous Alder Hill Avenue in Meanwood.

Look out for the long purple male catkins, alongside smaller bud-like female catkins. The small alder cones are also often visible right through the winter.

If you want to know more about Alder first you have to imagine a clog-wearing electric guitarist serenading you on the Rialto Bridge in Venice. Bear with me on this.

Her guitar is a Fender. Nearly all Fenders since 1956 has been made from Alder. According to Fender "Alder boasts many sonic advantages. Not especially dense, it’s a lightweight, closed-pore wood that has a resonant, balanced tone brighter than other hardwoods, with a little more emphasis in the upper midrange. It imparts excellent sustain and sharp attack. It’s very easy to work with and it glues well".

The clogs on her feet are also made of Alder as was the case with clogs throughout the industrial revolution - and they are really comfortable. Alder is reasonably soft and in time will become moulded into the shape of the wearers feet.

Finally the Rialto Bridge itself. Its base is made of Alder too. Alder is unusual in that exposure to water makes it harder, and it doesn't rot. The bridge has been standing on the same Alderwood foundations for at least 1000 years. Pretty impressive I reckon.

Posted on 11 January, 2023 15:48 by clunym clunym | 0 comments | Leave a comment

18 January, 2023

Species Of The Week Number 17: Golden Shield Lichen

Lichens are truly fabulous. Also there isn't much colour around at the moment so this Golden Shield Lichen provides a welcome exception.

The first thing to know about lichens is that they are not one organism but two. A lichen is partly a fungus - but the fungus can't photosynthesise (ie it can't turn sunlight into sugar) so it needs help. It gets that help by providing a home for a green algae which does the photosynthesis on its behalf. Together the fungi and the algae make up the lichen.

The algae of our Golden Shield Lichen is called Trebouxia. Trebouxia can also exist by itself - it just doesn't thrive quite so well without its fungal chum. It also gets everywhere and is found in both polar regions as well as in fresh and salt water and in the desert. I bet it prefers Meanwood though.

The second thing to know about lichens is that many are sensitive to air pollution and are used by researchers to help measure air quality. As a rule of thumb, the smaller and less variety of lichens in an area, the more polluted is the environment. Luckily though Golden Shield Lichen is one lichen isn't that bothered - which is probably why it doesn't mind hanging about near Meanwood Road. In fact it is quite keen on high levels of nitrogen and loves nothing more than a bit of seabird droppings, so is even more common at the coast.

The third thing to know about lichens is that they are are old. Like REALLY old. Humans emerged in Africa about 2 million years ago. Lichens have been here for at least 45 million years, one of the very first organisms to colonise dry land.

There are of course way more than three things to know about lichens. Books have been written on the subject. Lots of books. Just in case you are short of some holiday reading.

Posted on 18 January, 2023 18:02 by clunym clunym | 0 comments | Leave a comment

25 January, 2023

Species Of The Week Number 18: Lesser Redpoll

Lesser Redpoll is one of the winter visitor to Meanwood Valley. The best place to see them is on Birch or Alder trees, with the young woodlands planted around the Urban Farm is a good place to start. Sooner or later (probably later - Sod's law) a flock of these small finches will appear, hanging upside down and acrobatically feeding on the seed cones. There is a flock of 20-30 birds in the area at the moment.

I say 'Lesser' Redpoll but identifying different Redpoll species is quite controversial in the bird world, even involving DNA analysis. At some point there were officially 5 different species, but this is now generally accepted to have reduced to 3: The Common, the Lesser and the Arctic Redpoll. Some scientists even think they are actually all the same species. I'm sure more people would know about this if academics gave catchier titles to their work: 'Mitochondrial DNA homogeneity in the phenotypically diverse redpoll finch complex' ain't going to fly out the doors of Waterstones any time soon.

Redpolls are tough little things and readily survive temperatures of -50°c in Northern Canada. In order to do so they have developed a few coping strategies. For instance, their winter feathers weigh twice as much as their summer feathers giving added insulation. They also have a throat pouch where they store undigested food until they need it at night, increasing the number of calories they can take on. But perhaps the most unusual adaption is that they actually dig little tunnels in the snow and sleep in them to keep warm. (If you don't believe me there is a video on YouTube).

If you are VERY lucky you might even get a Redpoll visiting your Meanwood bird feeder. Luckier than me anyway, I've not seen one in 23 years of putting seeds out here. Talking of which, this weekend (January 28th -30th) is the RSPB's Big Garden Birdwatch. It's the world's biggest wildlife survey will have over 1 million people taking part. In the 2022 Birdwatch the Redpoll was the 50th most common species seen in West Yorkshire, that means it was only recorded in about 1 in a thousand of the West Yorkshire counts. By the way you don't need a garden to join in as you can also count species in your local park for an hour. If you want to take part all the details are just a Google search away.

Posted on 25 January, 2023 10:18 by clunym clunym | 0 comments | Leave a comment