This topic entails the following:

• Crop rotation
• Reasons for crop rotations
• Crop rotation programme
• Terms used in crop farming
• Mulching
• Reasons for various field management practices
• Correct stage for harvesting crops
• Harvesting practices of various crops.

            The following relevant questions and their answers in this topic will greatly motivate and help the             user to comprehend and understand the required concepts and practices:

1. Distinguish between staking and propping as a field management practice on crops
2. Explain five advantages of crop rotation                                                                               
3. State four factors which influence the stage at which the crops are harvested
4. The diagrams labelled B and C below are illustrations of coffee plants established using two

            different formative pruning systems.                                                                                     

            Examine the diagrams and answer the questions that follow:-

(a) Identify the system of pruning illustrated in B                                                                            

            (b) Identify the system of pruning in C                                                                                             

            (c) Outline the procedure of how pruning in diagram C is carried out                                             

5. Give two functions of earthing up in crop production
6. Describe the factors which determine the stage of harvesting of crops
7. Give two ways in which inorganic much helps to conserve water
8. State four factors that determine the spacing of annual crops
9. Explain the importance of each of the following practices: (i) Hardening off

                                                                                                            (ii) Pricking out

                                                                                                             (iii) Gapping 

10. Outline two factors that determine the stage of harvesting crops
11. (a) List four factors that determine harvesting sage of a crop

            (b) Give four practices that can be used to control storage pests                                         

12. List four benefits of pruning in crop production
13. (a) What is winnowing?

            (b) Give one importance of the following practices: (i) Mulching                                                                                                                                                    (ii) Threshing                                                 

(c) Which factors are considered when carrying out a crop rotation program?                    

14. What is frelishing?
15. Briefly explain how each of the factors listed below will determine the stage at which a crop is harvested

            (a) Intended use of the crop                                                                                                   

            (b) Market demand                                                                                                                

16. What is roguering in crop production?
17. What is meant by the term “changing the cycle” in coffee growing?
18. The diagram below shows a practice carried out on various crops on the farm. Study them

            carefully and answer the questions that follow;

            (a) Identify the farm practice represented by B                                                                     

(b) State the importance of the above practice in the following crops;                                 

      (i) Maize

            (ii) Irish potatoes       

            (c) At what stage of growth should the above practice be carried out in maize?                  

19. Mention four factors which determine the stage at which crops are harvested
20. State two limitation of using polythene sheets as mulching materials in a field of tomatoes
21. Give two management practices carried in a banana stool
22. State two functions of polythene sheet when used as mulch material
23. Give four crops requiring training

CROP PRODUCTION IV

(FIELD MANAGEMENT PRACTICES)

1. Staking is supporting tall varieties of tomatoes using a stick fixed next to the plant and tied with

             sisal string while propping is supporting banana plant with sticks Mark as a whole= 1 mk

2. five advantages of crop rotation

• Improves soil fertility: where legumes are included nitrogen is fixed/ added in the soil
• Control pests and diseases: disrupts the life cycle of certain pests and diseases
• Control weeds: control weeds which are specific to certain crops e.g. striga in cereals/ cover crops in a rotation will smother certain weeds
• Better use of the soil nutrients: different crops (due to differing root systems) draw nutrients from varying soils horizons/ different crops require different nutrients
• Control of soil erosion: cover crops included reduce soil erosion
• Improve soil structure: When grass lays are included which during the period organic matter will accumulate to enrich the soil and improve soil structure

3. four factors which influence the stage at which the crops are harvested.

            – Purpose of the crop / maturity.

            – Moisture content.    

            – Concentration of certain chemicals.

            – Water condition.

            – Market demand.

4. a) B.   –  Single stem pruning system.            (1×1=1mk)
5. b) Identify the system of pruning in C.

            – Multiple stem pruning system.         (1×1=1mk)

1. c) Outline how pruning in diagram C is carries out.

– Main stem of the seedling is capped/ cut stem at 38 – 60 cm high.

            – Two or three suckers are selected and allowed to grow while the rest are removed

5. Two functions of earthling up in crop production

• To influence tuber expansion
• To retain water between the ridges which increases water conservation/infiltration
• Reduces soil erosion

–    To prevent the greening effect in potatoes

6. (a) The factors which determine the stage of harvesting of crops

• Stage maturity of the crops
• Use of the crop
• Tastes and preferences of consumers
• Weather conditions
• Chemical conditions
• Chemical concentration of the chemical
• Moisture content ( 1mk x any 6pts = 6mks)

7. – Reduces runoff thus increasing amount of water into the soil

Reduces evaporation thus increasing the amount of water retained

8. – Moisture content of soil

• Use of which the crop is to be put
• Number of seeds per hole
• Prevalence of certain diseases/ pests
• Machinery to be used in subsequent operations
• Fertility status of the soil

9. i) To acclimatized the seedlings to direct light/ conditions in the seedbed
10. ii) To avoid overcrowding and reduce competition for light.

            iii) Produce healthy and strong seedling

1. iv) To obtain correct plant population
2. Two factors that determine the stage of harvesting crops are:-

• Purpose of crop
• concentration of required chemical

11        a)    –   Weather condition                                                                                                      

• Use/ purpose
• Stage of growth
• Concentration of the required chemicals (i.e. tea) ( ½ x4=2 mks)

1.  b)    –    Proper drying of produce

• Keeping storage facility/ structure clean
• Use of pesticides on storage structure
• Treating produce with pesticides e.g. cereals

Use of rodent guards                    

12. Enable controlling over bearing by ensuring required leave ratio

• Open up canopy for air and light penetration
• Reduce chemical waste
• Control pests and diseases
• Allow other field operation

Give crop desired shape   

(c) Which factors are considered when carrying out a crop rotation program?                    

13. a) -Removing of chaffs by use of wind

            b)i)-  Prevent erosion

• Add organic matter
• Conserve soil moisture
• Raise soil temperature ( ½ mk)

1. ii) – improve quality of grains by separating them from rest of plant (½ x1= ½ mks)
2. c) – Root systems of crops

• Botanical relation of crops
• Nutrient absorption by plant

Susceptibility to pests, diseases or weeds

14. a)This is support  given  to crops with  weak stem. So as to grow in the desired direction
15. b) -Makes the plant to get enough sunlight to manufacture food i.e. prevent shading

             -leads to more productivity

-reduced infections of diseases from the grounds

15. (a) Some crops are harvested earlier e.g. maize for silage at silking stage while maize for grains when the grains are dry;                                                                                          

            (b) A crop can be harvested earlier when the market demand is high;

16. It is a farming practice that involves the removal and destruction of crop plants which are heavily

             infested with pests and diseases from the field.

17. It is the replacement of old bearing stems by suckers. The cycle is usually changed

           after 4 – 6 years.

18. a)- Earthening up
19. b) Importance of the above practice
20. i) Maize – provides support to prevent lodging
21. ii) Irish potatoes – Improves tuber formation
22. c) During second weeding
23. Four factors which determine the stage at which crops are harvested                     

• Original  conditions of land
• Soil type
• Cost
• Size  of  planting materials
• Soil moisture type of implement

20. Two limitation of using polythene sheets as mulching materials in a field of tomatoes Expensive

• Requires skilled labour
• Does  not  decompose

May overheat soil around  crop roots

22. – suckering

            -Pruning of leaves

            -Propping

            -Mulching

            -Earthing up

23. – Smothers weeds

            -Regulate soil temperature

            -Conserve moisture

25. -passion fruits

            -Deep rooted

            -Nitrogen fixing

            -Good by-products

            – Friendly too crops / not affent crop