28 Leaf casting. (A walk) 



This process is something like what goes on in the 

 woods. The fallen leaves cover the ground thickly and, 

 as they lie there exposed to the damp and to the air, 

 they rot away and leave in their place a thin layer of 

 rich dark soil. In a wild wood this humus, as the leafy 

 top soil of the woodlands is called, goes on collecting 

 year after year and provides the trees with just the food 

 they want. If, however, the dead leaves in a wood are 

 collected and taken away, the trees will be half starved, 

 for when they lose their leaves they will get nothing 

 back from them as they would have done if left alone. 



PRACTICAL WORK. 



You will be taken for a walk to study leaf falling. Notice the 

 following points : 



1. Are some kinds of trees barer than others ? If so, which ? 

 What kinds of trees show least change in their leaves ? 



2. Do you see any trees whose leaves though quite brown are 

 not falling ? If so, which ? 



3. Can you find on any tree a twig or branch which has been 

 partly broken off in the summer and has died ? What is happening 

 to the leaves on such a branch ? 



4. Collect leaves from under any one tree to show four to six 

 stages of change of colour. 



HOME WORK. 



1. Draw the outlines of your leaves in pencil (natural size) and 

 paint them to show the different stages of colouring. 



2. Take home with you from your lesson two acorns and two 

 scarlet runner beans. Place them in a saucer half full of water. 

 Look at them at about the same time every day and write down on 

 a piece of paper any change you notice in them and the day on 

 which you saw it. You will want these notes for your home work 

 next week. Also draw in pencil each day an outline sketch showing 

 these changes. 



