Falling Leaves on a Woodland Walk

Autumn has moved on a pace and the beautiful colours are starting to fade and the leaves are falling at great number. Indeed as November gets into full swing and the weather takes a turn for the worse, you get a sense of the Autumn slipping away into winter. Despite this we still headed out for a wildlife adventure. We decided to go slightly outside Worcester to The Knapp and Papermill near Alfrick.

The Orchard

 This is a beautiful nature reserve managed by the Worcestershire Wildlife Trust. There is a range of habitats, which includes woodland and the Leigh Brook. As a result it is a great place to take the family to engage with wildlife as there is always something to see. This visit did not disappoint.

Leigh Brook

One of the top species that the reserve is meant to home is the Dipper. One of my favourite birds, I just get transfixed by its repeated bobbing up and down beside the river rapids. They bob for a few seconds and then they dive into the fastest flowing section of the river before returning to the surface with a meal of invertebrates, they are true wonders of evolution. Their adaptions have been covered in a previous blog.

Carpet of Leaves

On all my previous visits to the Knapp and Papermill I have never seen a dipper. I was wondering if their presence was fictitious, but I am always hopeful. On the walk I stopped by a collection of trees where there was a flock of long-tail tits. Scanning through I was really pleased to see a marsh tit and a number of goldcrest's. Whilst I was watching I heard an excited shout from along the path “dipper” indeed a dipper had been spotted. We waited and watched it for a few minutes before it flew along the path. We went on to spot total of three on our walk.

Dipper

As we walked around the reserve getting blown in every direction we became aware of the amount of leaves that were being blown by the wind. It is a fun game to play to try to catch a falling leaf; unfortunately our children are a little too old for that. However, we all started wonder if the losing of leaves is entirely down to the wind? It is easy to see how we connect the weather to the act of leaves falling. 

Orange Ladybird - Halyzia sedecimguttata

However, it is kind of obvious that there is more to it than the weather. Leaves drop when the weather is still and conversely brown leaves remain on the trees when the weather is at its most brutal. There is in fact a more scientific explanation to the leaves falling from the trees other than weather and the tree itself controls the process. It is called abscission.

Meadow

When the leaf has broken down all the leaf chemicals such as chlorophyll and removed them from the leaf the tree will stop the auxin. Auxin is a growth hormone. As the Auxin levels diminish the tree increases the ethene levels in the leaf. This causes an area between the branch and the leaf to develop an abscission zone. Here specialised cells break the leaf away from the branch. They do this by using enzymes to break down the cell walls. The result is a clinical separation of the leaf and the tree branch.

Woodland

Abscission is an amazing process and it is a real shame that the wind takes all the credit. It is also worthy to note that this process it is not only seen in the autumn. Evergreen plants do it throughout the year. It is also the same process that is used by plants to discard flowers, seeds and fruit. Indeed it is the same word used in mycology to disperse the fungal spores; perhaps that is for another blog. We just enjoyed the splendour and beauty of a woodland carpet of fallen leaves and learnt some science in the process.