Wild-Flower Study 



565 



Method — A thistle plant 

 brought into the schoolroom — ■ 

 root and all — and placed in water 

 will serve well for this lesson. 

 The questions should be given 

 the pupils as to where thistles 

 are found. Any thistle will do 

 for the lesson. 



Observations — i. Where do 

 you find the thistles growing? 

 Do you find more than one spe- 

 cies growing thickly together? 

 Do you find any of the common 

 thistles growing in soil which has 

 been cultivated this season ? 



2. Describe the stalk, is it 

 smooth? Is it weak or strong 

 and woody? What sort of root 

 has it? 



3. Do the leaves grow alter- 

 nately or opposite? Are they 

 smooth or downy on one or both 

 sides? Do the spines grow 

 around the margins, or on the 

 leaves and veins? Are the leaf 

 edges flat, or wavy and ruffled? 



4. How does this affect the 

 direction in which the spines 

 point? Are the leaves entire or 

 deeply lobed? Have they peti- 

 oles, or are they attached directly 

 to the stalk? 



5. Note if any buds or small 

 branches nestle in the axils of 

 the lower leaves. What effect 

 does cutting the main stalk seem 

 to have on each side shoot? 



6. Do the flower-heads of the 

 thistle grow singly or in clusters? 

 Do they come from the summit 

 of the stalk, or do they branch 

 from its sides? Which blossom- 

 heads open first — the topmost or 

 those lowest on the stalk? Are 

 the flowers fragrant? What in- 

 sects do you most often see 

 visiting thistle blossoms for pol- 

 len or nectar? Study the thistle flower according to Lesson CXXXV. 



7. Carefully study a thistle balloon. How is the floss attached to the 

 seed? Is it attached to the smaller, or the larger end? Hold the thistle 

 balloon between your eye and the light. Does the down consist of single 

 separate hairs, or have they many fine branches? How is the down 



The Canada thistle. 

 Drawing by W. C. Baker. 



