Priestgate

Acer platanoides – The Norway Maple

Leaves make the sugary food that their host plant needs to live. Everyone knows that …. don’t they?

But the thing is …. how do they do it?

Acer platanoides ‘Crimson King’

So, leaves are green (except when they’re not), and even leaves which don’t appear to be green have the green pigment within them.

This green pigment is called ‘Chlorophyll’. It is an essential ingredient in this whole process, as are Carbon Dioxide from the surrounding air, and sunlight.

These three ingredients are what much of plant life absolutely depends upon.

A young plant turning its leaves towards the Sun

But it’s a big ask to believe that these ingredients can end up having helped to create things like plants, and the way that they acquire food.

So, how does it work …. and does it have a name?

The process is called Photosynthesis.

In very simple terms, what is happening here is that the leaf draws Carbon Dioxide from the surrounding air into itself.

Once inside the leaf, together with the green pigment(Chlorophyll) and daylight, these combine to create two things at the same time.  Carbohydrate, a sugary substance, and Oxygen.

The Carbohydrate is kept, but the Oxygen is released back into the air.

What is also evident from this diagram is the movement of water within the plant. This too is in the most part to do with the leaf as well.

Within the plant, water exists as huge chains of water molecules which extend upwards from the roots to the leaves at the very top.

As a leaf presents itself to the air, water from within it evaporates one molecule at a time.

As each molecule leaves the leaf, the next one is drawn upwards in a chain which extend to the root, so that as one leaves the leaf, one is drawn up from the soil, together with the mineral elements and anything that results from the addition of fertilizer.

So water and its contents travel up in one type of connective tissue called ‘xylem’, and carbohydrate travels down in another called ‘phloem’.

Each tissue type exists like a sheath at the very outside of the plant, just beneath the bark. The minerals from the water going up are shared between the living cells within the plant,  as is the carbohydrate going down.

The difference with the carbohydrate is that if there is any left by the time it reaches the root system, then it can be stored within it.

And from there comes the energy that is necessary in deciduous plants for their buds to swell and leaves to develop in the spring.