Sunday, 6 April 2014

Flat to the mat

Everything is now progressing at full speed: I saw the first House Martins last week and Swallows will be around in the next day or two.

A few trees are in leaf, with Willow leading the way as usual:

Willow leaves

Hawthorn wasn't far behind, and hedges are now greening up very nicely:

Hawthorn leaves
Notice that the leaves are all in pristine condition. That won't last long once the caterpillars and leaf-miners wake up and start feeding. This synchronisation between insect and foodplant is very well illustrated by the Beech leaf-miner Orchestes fagi: the instant the Beech leaves unfurl, the female weevil lays her eggs on the central vein of the leaf and the miner starts to tunnel towards the leaf margin. A few days later, the mine is complete and the next generation flies off to start the cycle all over again. The synchronisation in this association between two species is critical, since the leaf is only soft enough to eat for the first few days after opening: after that it's too tough. Keep an eye on Beech trees towards the end of the month and you should see the mines within a couple of days of the leaves appearing.

A few flowering plants are now producing flowers more or less all year round and are in flower alongside the spring-flowering species. I suppose we are now warm enough for hardy species to keep going through milder winters. This specimen of Red Dead-nettle has survived the few cold nights and has plenty of flowers already:

Red Dead-nettle
Other flowers that have survived continuously include Herb Robert, Sowthistle, Smooth Hawksbeard, Dandelion, Daisy and Bush Vetch. All of these are currently in flower here.
Other species are showing when conditions are right. This specimen of Dark-lipped Banded Snail is one of many colour variants of this common species:

Dark-lipped Banded Snail
I'll show other variants as and when they appear.

I'm always intrigued by the intense colours that can sometimes appear and then seemingly vanish without trace. This Daisy has an intense purple pigment to the tips of the petals, but the fully open flower will be more or less pure white:

Daisy bud, showing the purple petal tips
I suppose there is a fixed amount of pigment that is eventually shared over a larger area. Some fungi show exactly the same effect, getting paler as they mature.

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