WEEDS AND THEIR ERADICATION 133 



Questions: 



1. Tell what you can about annual weeds. Name some of them, 

 and tell how to eradicate them. 



2. Name two common biennial weeds, and tell how to destroy 

 them. 



3. Name the worst perennial weeds, and tell how to kill them. 



4. When might spraying be preferable to other means of erad- 

 ication? 



Arithmetic: 



1. If a man's time is worth 16c. per hour, and each horse's time 

 is worth 10c. per hour, how much does it cost per day for the labor of a 

 man and four horses? (10 hours for a working day.) 



2. If a man and 4 horses can harrow 40 acres per day, how much 

 does it cost per acre to harrow land? (Is not harrowing a cheap way 

 to kill weeds?) 



3. Morning-glories twine about and kill 200 hills of corn on an 

 acre. What part of the crop is thus destroyed? (There are 3,240 

 hills per acre.) 



4. If iron sulphate costs $20 a ton, how much would it cost per 

 acre for material at the rate of 50 pounds to the acre? 



Exercises: 



1. Bring to school each day a different kind of a weed and see 

 how long you can continue bringing a different one each day. 



2. It will be a very valuable exercise for you to gather, press and 

 mount samples of all of the weeds you can find, so that you will know 

 them wherever you see them. 



3. Put a handful of salt on a dandelion plant and see what hap- 

 pens in a day or two. 



4. Bring to school samples of uncleaned grain. Separate the 

 weed seeds from the grain. Learn to identify as many different weed 

 seeds as you can. 



