SAMPLE FINAL EXAMINATION 2

l. Explain why the C/N ratio of organic matter normally narrows with composting.

____________________________________________________

____________________________________________________

____________________________________________________

____________________________________________________

What is the main advantage of narrowing the C/N ratio through composting of organic matter?

____________________________________________________

____________________________________________________

____________________________________________________

____________________________________________________

What are the major losses or disadvantages in composting?

a. _________________________________________________

b. _________________________________________________

c. _________________________________________________

2. What is the principal purpose of incorporating a green manure into a crop rotation?

____________________________________________________

____________________________________________________

____________________________________________________

What are two secondary or special benefits (other than that listed above) received from a green manure crop?

a. ________________________________________________

b. ________________________________________________

What characteristics of a crop should one select in choosing a good green manure crop?

a. __________________________________________________

__________________________________________________

b. __________________________________________________

__________________________________________________

c. __________________________________________________

__________________________________________________

How does one determine when to turn the green manure crop into the soil?

a. _________________________________________________

_________________________________________________

_________________________________________________

b. _________________________________________________

_________________________________________________

_________________________________________________

3. What are the differences in root distribution between a mulched and an unmulched crop?

______________________________________________________

______________________________________________________

______________________________________________________

Relate the differences to the management of mulches. _____________________________________________________

______________________________________________________

______________________________________________________

______________________________________________________

4. List four mulching materials and a function of each one.

a.___________________________________________________

_____________________________________________________

b.____________________________________________________

_____________________________________________________

c.____________________________________________________

_____________________________________________________

d.___________________________________________________

____________________________________________________

 

5. Circle the plant nutrients among this group of elements.

copper nitrogen iron

zinc potassium sulfur

magnesium sodium cobalt

strontium calcium phosphorus

fluorine boron neon

chlorine molybdenum cesium

bromine vanadium rubidium

manganese aluminium selenium

 

6. Comment on the truth of the following statements.

a. The kind of nutrients used by plants is the same whether the nutrients are supplied organically or by conventional means.

________________________________________________________

________________________________________________________

________________________________________________________

________________________________________________________

b. Nitrogen fertilization is included normally in any program of soil management.

_________________________________________________________

_________________________________________________________

_________________________________________________________

_________________________________________________________

c. Organic farmers run deficits in their programs for phosphorus and potassium fertilization.

___________________________________________________________

___________________________________________________________

___________________________________________________________

6. Explain the meaning of the following terms.

a. 5 - 10 - 10 grade of fertilizer_________________________________

________________________________________________________

________________________________________________________

b. Nutrient deficiency symptom__________________________

________________________________________________________

________________________________________________________

c. Availability of nutrients in soil____________________

________________________________________________________

________________________________________________________

d. Nutrient immobilization______________________________

________________________________________________________

________________________________________________________

e. Crop lodging_________________________________________

________________________________________________________

________________________________________________________

 

7. Why is only about 3 to 20% of the phosphorus in chemical fertilizers available to a crop during the first season after the application of the fertilizer?

________________________________________________________

________________________________________________________

Why is it not advisable to use rock phosphate if the pH of the soil is above 5.5?

________________________________________________________

________________________________________________________

List two chemical processes through which the addition of organic matter increases the availability of phosphorus in the soil.

a._______________________________________________________

_________________________________________________________

b._______________________________________________________

_________________________________________________________

8. What features distinguish an organic fertilizer from a conventional chemical fertilizer?

a.______________________________________________________

________________________________________________________

b.______________________________________________________

________________________________________________________

9. Evaluate the following materials as organic fertilizers.

a. Plant materials______________________________________

________________________________________________________

________________________________________________________

________________________________________________________

________________________________________________________

b. Animal tissues_______________________________________

________________________________________________________

________________________________________________________

________________________________________________________

________________________________________________________

c. Natural rock materials_______________________________

________________________________________________________

________________________________________________________

________________________________________________________

d. Waste materials______________________________________

________________________________________________________

________________________________________________________

________________________________________________________

________________________________________________________

 

10. Comment on the effectiveness of following practices of plant disease control.

a. Selection of disease-resistant plant varieties ________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

b. Control of weeds and insects in immediate vicinity of a vegetable garden ______________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

c. Provision of good drainage conditions in the soils of a flower garden _________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

d. Whitewashing the trunks of apple trees ___ ________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________