Tree Project

By Claire Tancell

Why are trees important?

Trees are all around us. They help to change carbon dioxide CO2 into the oxygen O2 we need to breathe. They provide food and shelter for wildlife and us. They are an important part of our ecosystem.

Getting started.

First, choose a tree. If you can, find one that has plenty of room around it for you to work in. You might like to choose one that you can visit at different times of the year to see how it changes.

What you will need

There is a lot that you can learn about trees with just your senses, but you may find it useful to have: Pencil, Piece of old sheet or white paper, Small container (eg yoghurt pot), Magnifying glass

Trees can be divided into two groups; deciduous trees, which lose their leaves in winter and evergreen trees, which keep their leaves all year round. Deciduous trees usually have broad leaves while evergreens usually have needles or narrow leaves. You can tell what species of tree you have by looking at:

Leaves
Bark
Twigs and buds
Flowers
Seeds and fruit
Tree Shape

.An oak leaf and acorn (Deciduous)

.
Pine leaves and cone (Evergreen)

You can use tree identification guides to find out what kind of tree you have.

Lichens and air quality

Looking at what is growing on the tree trunk can tell us how clean the air is. You will see more bushy species of lichen (an organism which is part fungus and part algae) where the air is clean.

More air pollution

The more kinds of lichen you find the more likely the air is to be clean and unpolluted. If you find lichen on a tree look and see which side it is growing on. It is more likely to be growing on the sunny south side as lichens need plenty of light. On the darker north side you may find mosses. Mosses have leaves and need moisture. They are always green. Lichens don't have leaves and are usually grey, yellow or brown. Try taking a piece of white tissue and wiping a leaf on the tree. Is there dirt on the leaf?

Trees are home to lots of invertebrates. Some live on or in the tree itself and others in the area around it. The leaves and branches of the tree are known as the canopy, and the area of fallen and decomposing leaves under the tree is called the leaf litter.

Tree minibeasts

A good way to look at these small creatures more closely is to catch them using some simple techniques…

The canopy:
Take a large piece of light coloured paper or an old sheet and lay it under the tree. Use a long stick or broom to gently shake the branches of the tree. Have a look at the paper and see what has fallen from the canopy. Here are some of the things you might find.

Photo © Michael Demidecki

Ladybird

Weevil

Lacewing

You could use a magnifying glass to look more closely at what you have found.

The tree trunk:
Take a close look at the trunk. Just by looking, you will probably find some invertebrates on the bark. If there is any loose, dead bark coming off the tree, try lifting it gently to see what is underneath. Don’t pull off big chunks or you will hurt the tree! You may find an ant, a bark beetle, a moth, a spider or a harvestman.

The leaf litter:
You may see some invertebrates on the leaf litter beneath the tree. Try turning over stones or leaves that are on the ground to see what is underneath. Remember to put back anything that you move.

A good way to see what is living in the leaf litter is to build a pitfall trap. Make a hole big enough to fit a small container so that the top is level with the soil surface. Cover it with a large flat stone or piece of wood leaving some gaps for invertebrates to crawl through, and leave it for a while.

Pitfall trap

Here are some of the things you might catch in your pitfall trap…

1. Ground Beetle 2. Millipede

Draw some pictures of the invertebrates that you found…

In the tree canopy

On the tree trunk

In the leaf litter

Phenology

Phenology is the recording of things that happen in nature because of the changing seasons. Things like hearing the first cuckoo of spring, seeing the first swallow of summer, noticing the first leaf fall in autumn or the first primrose flower in spring. The British Naturalists’ Association (BNA) has been recording phenological data for a hundred years. It can tell us about how the seasons are changing and the effects of global warming on our planet. You can add to this important information by recording some information about your tree.

The tree species you looked at.

The date that leaves first appeared on your tree in spring.

The date that the leaves began to fall from your tree in autumn.