A STUDY OF AUTUMN WEEDS 



27 



Color, perfume, nectar. The showy flower is an advertisement to the 

 insects that their presence is desired. The attractive color is often supple- 

 mented by pleasing odors. The visiting insect is also enticed by nectar. 

 You have probably bitten off the spur of a violet or a columbine blossom 

 to taste this. Color lines and blotches on the blossom sometimes point 

 the way to the desirable nectar. As in the ancient world all roads 

 led to Rome, so in the flower world all lines lead to the nectar. 

 (Read W. Hamilton Gibson's "Welcome of the Flowers" in Harper's 

 Magazine, LXXXVIH, 551-56. This will give an idea of the devices 

 found in blossoms to insure their cross-pollination by 

 insects.) 



Personal observations. Study some particular 

 plant to see: (i) how many insects come to a blossom 

 like milkweed, horsemint, fireweed, or red clover in an 

 hour; (2) whether one sort of insect, like the bumblebee, 

 fly, butterfly, or honeybee, confines its attention to a 

 particular flower or whether the flower in question 

 welcomes all sorts of insects; (3) in what ways a 

 particular flower is adapted to a particular insect. 

 The following are some good plants to watch: butter 

 and eggs, spotted balsam, evening primrose (why 

 "evening"?), beardtongue, horsemint, nightshade, 

 Jimson weed, and rose mallow. Record your observa- 

 tions on the opposite page. 



The study of a familiar weed, a dandelion. Dig up a dandelion. What 

 sort of a root has it ? Is this an advantage or disadvantage to the plant ? 

 Do dandelion roots have a commercial value ? How are the leaves of the 

 dandelion arranged? Name some other plants that have the rosette 

 habit. In what way is this profitable to the plant ? Do dandelions 

 blossom early in the spring ? Can you see what makes this possible ? 

 Draw an outline of a dandelion leaf. Is the shape of the leaf in any way 

 dependent upon arrangement of leaves on the plant? What is the taste 

 of a dandelion leaf ? Would this be of any service to the plant ? What 

 is commonly called the dandelion blossom is really a cluster of blossoms, 

 each one very small. Compare a single blossom with this sketch, and 

 record the parts as we have seen them in our study of the mustard flower. 

 What benefit would the plant derive from having the tiny blossoms bunched 

 as they are here or in a clover bloom? Observe a dandelion plant in 

 blossom. Are the stalks on which the blossom clusters are held standing 

 up straight or lying down ? Do the stalks bearing the seed cluster or " blow 

 balls" stand up or lie down? What is their position in wet weather? 



FIG. 4. Single 

 flower of dandelion. 



