1 1 10 



Home Nature-Study Course. 



increase in numbers and strength until they are able to develop the mushrooms, 

 which are simply the fruiting organs. Highly fertilized soil, permeated with, 

 these mushrotim threads, is often cut into bricks or large cakes and sold for the 

 purpose of starting new mushroom beds. The commercial term for these bricks 

 is " spawn." Upon these threads the buttons grow. We may find them in regular 

 mushroom beds, from the size of a pinhead up. 



Lesson II 



BRACKET FUNGI 



Purpose. — To help the children understand that the fungi which 

 we see growing shelf-like from trees are deadly enemies to the trees. 

 Their spores germinate and penetrate at some open wound and the grow- 

 ing fungus weakens the wood. 



Metliod and material. — It is 

 desirable that a tree on whicli 

 shelf -fungus grows should be 

 studied by the class, for this is 

 a lesson on the care of trees. 

 After this lesson the fungus it- 

 self may be studied at leisure 

 in the school-room. 



Observations by pupils-' 

 (i). On what kind of tree is 

 the bracket fungus growing? Is 

 it alive or dead? If living, does 

 it look vigorous or is it decaying? 

 (2). Is the fungus bracket 

 growing against the side of the 

 tree or does it stand out on a 

 stem? 



(3). Look at the place where the bracket joined the tree. Does it seem 

 to be part of the wood? 



(4). What color is the fungus on its upper surface? How large is 

 it ? How thick near the tree ? How thick at the edge ? Can you detect 

 concentric layers or rings ? If it is the large species used for etching, cut 

 down through it with a knife or hatchet and count the layers; this 

 should show its age. 



(5). Look at the lower surface. How does it appear to the naked eye? 

 If you scratch it with a pin or knife does the bruise show? Examine 

 the surface with a lens and describe what you see. Cut or break the 

 fungus and note that each of these holes is an opening to a little tube. 

 In each of these tubes spores are borne. 



A shclf-fnugus. {Polyponis apphviatus). 



It grew in this position on the tree — 

 after the tree was felled — new brackets 

 grew at ri^ht angles, so that the spores 

 should grow on the under side. 



