Agriculture Paper 1 Questions and Answers - Lainaku II Joint Mock Examination 2023

Instructions to students

• This paper consists of three sections: A, B and C
• Answer all questions in sections A and B
• Answer any two questions in section C
• Candidate should answer the questions in English

Section A. (30 Marks)
Answer all questions in this section in the spaces provided.

1. What is organic farming? (1 mark)
2. Give three reasons why burning is discouraged in land-clearing (1½ marks)
3. Give two cultural methods of controlling bollworms in a tomato crop. (1mark)
4. State three ways through which agricultural activities pollute water (1½ marks)
5. List two advantages of proper stocking rate in pasture management (1mark)
6. State three ways through which mono-cropping leads to loss of soil fertility (1½ marks)
7. State the law of diminishing returns in economics (1mark)
8. State four factors to consider when deciding on a farming system to undertake (2 marks)
9. Give two benefits of earthing-up in Irish potatoes production (1mark)
10. List four steps followed in land adjudication (2 marks)
11. Give two factors that determines the depth of ploughing (1mark)
12. List four methods of fertilizer application (2marks)
13. Give four precautionary measures that a farmer should put into consideration when harvesting cotton (2 marks)
14. State four factors that should be considered before deciding to use a chemical method of pest control. (2 marks)
15. State four ways in which grass cover help to conserve soil (2 marks)
16. Give four advantages of rotational grazing (2 marks)
17. State three advantages of landlordism and tenancy land tenure system (1½ marks)
18. State three benefits of using tissue culture in crop propagation (1½ marks)
19. How are following conditions prevented in carrot production (1½ marks)
    1. Cracking
    2. Forking
    3. Greening
20. List two micro-catchments systems in water harvesting ( 1 mark)

Section B: (20 Marks)
Answer all questions in this Section on the spaces provided

1. The diagram below shows a pruning method in coffee. Study it and answer the questions that follow
   
   1. Identify the pruning method illustrated above (1mark)
   2. Explain how the pruning illustrated above is carried out (2½ marks)
   3. State three reasons for pruning in coffee (1½ marks)
2. The diagrams below shows some storage pests. Study them and answer the questions that follow
   
   1. Identify the pest a, b and c (3marks)
   2. State two kinds of damages they cause to stored produce (1mark)
   3. State two methods which can be used to control storage pests (1mark)
3. The diagram below shows two different weeds x and k. Study them and answer the questions that follow
   
   1. Identify the weeds x and k (2 marks)
   2. On basis of plants morphology, identify the class of weed x (1 mark)
   3. Give one disadvantage of weed k (1 mark)
   4. Give one beneficial use of weed x (1mark)
4. Below is a diagram of a compost pit. Study it and answer the questions that follow
   1. Identify the layers A, B, C, D and E (2½ marks)
   2. State two importance reasons of layer B (1 mark)
   3. State the functions of the stick and the grass cover (1 mark)
   4. Name the other method of making compost manure (½ mark)

Section C: (40 Marks)
Answer any two questions in section on the spaces provided after question 24

1.  
   1. Describe the risks and uncertainties encountered by wheat farmers in Kenya. (7 marks)
   2. State the importance of Agroforestry (7 marks)
   3. Outline six factors that affect rooting of cuttings (6 marks)
2.  
   1. Discuss the influences of soil structure on crop production (7 marks)
   2. Outline six factors that influences price of a commodity or service (7 marks)
   3. Explain six types of pesticides according to their mode of action (6 marks)
3.  
   1. Describe the uses of farm accounts in the farm (8 marks)
   2. Explain six advantages of using seeds for crop propagation (6 marks)
   3. Discuss factors to consider when selecting implements to use for primary cultivation (6marks)

MARKING SCHEME

SECTION A (30 MARKS)

1. What is organic farming
   
   • The growing of crops and rearing of animals without use of agro-chemicals  (1 x1= 1 mark)
2. Three reasons why burning is discouraged in land clearing
   
   • Kills soil microorganism
   • Destroys soil organic matter
   • Destroys soil plant nutrients
   • Destroys soil structure (Any 3 x ½ = 1 ½ marks)
3. Give two cultural methods of controlling bollworms in a tomato crop
   
   • Early planting
   • Rogueing
   • Trap cropping ( Any 2x ½ = 1 mark)
4. Three ways in through which agricultural activities pollute water
   
   • Excessive application of agrochemicals which are washed to water bodies
   • Overgrazing leads to soil erosion and the eroded soil pollute water.
   • Poor disposal of chemical containers near water bodies.
   • Washing of farm machines and equipment near water bodies.
   • Use of inorganic fertilizers (Any 3 x ½ = 1 ½ marks)
5. Two advantages of proper stocking rate in pasture management
   
   • Controls soil erosion
   • Ensures adequate pasture for animals
   • Increases the useful life of the pasture crop (Any 2 x ½ = 1 mark)
6. Three ways through which monocropping leads to loss of soil fertility
   • Encourages infestation of soil pests and diseases.
   • Exhausts a particular type of nutrient
   • Exhaustion of nutrients from a particular root zone (3 x ½ = 1 ½ marks)
7. State the law of diminishing returns in economics
   • In a production process, if variable addition of inputs are increased while all the other factors are held constant, there will be an increase in additional output until a point is eventually reached when the additional output per additional unit of input declines
     (1x1 = 1 mark)
8. Four factors to consider when deciding on a farming system to undertake
   • Size of the farm
   • Type of soil in the area
   • Environmental factors
   • Availability of resources / capital
   • Cultural factors
   • Farmers knowledge and skills
   • Government policy and regulations (Any 4 x ½ = 2 marks)
9. Two benefits of earthing up in Irish potato production
   • Prevent greening of tubers
   • Improves on tuber formation
   • Improves on drainage around the crop (Any 2x ½ = 1 mark)
10. Four steps followed in land adjudication
    • Establishment of ownership
    • Description of the land / measurement
    • Recording / mapping of land
    • Checking any objections
    • Settling the objection cases if any
    • Registration of the land in the land registry
    • Issue of certificates / title deeds. (Any 4 x ½ = 2 marks)
11. Two factors that determines the depth of ploughing
    • Type of crop to be planted
    • The implements available
    • The type of the soil (Any 2 x ½ = 1 mark)
12. Four methods of fertilizer application
    • Broadcasting
    • Row placement / side dressing / banding
    • Hole placement
    • Foliar application
    • Fertigation
    • Top dressing (Any 4 x ½ = 2 marks)
13. Three precautionary measures that a farmer should put into consideration when harvesting cotton
    • Pick only fully opened balls.
    • Not to mix cotton with foreign materials.
    • Use separate containers for the two grades.
    • Avoid using sisal bags as container for balls.
    • Carry two baskets for sorting the two grades i.e AR or BR
    • Avoid rainy weather when picking the balls (Any 4 x ½ = 2marks)
14. Four factors that should be considered before deciding to use a chemical method of pests control.
    • Intended use of the crop
    • Time within which to use the crop
    • Costs of the pesticides
    • Safety of the pesticide to the user/Environment
    • When all other methods are inadequate. (Any 4 x ½ = 2 marks)
15. Four ways in which grass cover help to conserve soil
    • Reduces the speed of the run-off which lowers its erosive power.
    • Reduces / intercepts the impacts of the raindrops which reduce splash erosion.
    • Covers the soil surface hence reduce wind erosion.
    • The roots hold soil particles together from being carried by the erosive agents.
    • Organic matter from the grass improve the soil structure which will improve infiltration rate of water, hence reduce erosive power.
      (Any 4 x ½ = 2 marks)
16. Four advantages of rotational grazing.
    • Maximum use of pastures
    • Reduces build-up of pests and diseases
    • Animal waste are evenly distributed in the field
    • Pasture is given time to regrow
    • Excess pasture can be harvested for conservation
    • It’s possible to apply fertilizer in part of the pasture not being grazed (Any 4 x ½ =2marks)
17. Three advantages of landlordism and tenancy land tenure system
    • Landlords who cannot use land can get some income when they lease their land.
    • Land that otherwise would be idle is put into use.
    • Landless people can get access to land for use through renting.
    • Reduces land disputes. (Any 3 x ½ = 1 ½ marks)
18. Three benefits of using tissue culture in crop propagation
    • It is used to establish pathogen-free plants.
    • It’s used in mass production of propagules
    • It’s a faster method to produce propagules
    • Require less space than other methods (Any 3 x ½ = 1 ½ marks)
19. How are the following conditions prevented in carrot production
    1. Cracking – Regular watering
    2. Forking – Avoid addition of organic manure to the soil
    3. Greening – Earthing up the shoulders of the carrots ( 3 x ½ = 1 ½ marks)
20. List two micro-catchment systems used in water harvesting
    • Negarim
    • Contour bunds
    • Semi-circular bunds
    • Trapezoidal bunds
    • Contour stone bunds.
    • Permeable rock bunds. (Any 2 x ½ = 1 mark)

Section B: (20 Marks)
Answer all questions on the spaces provided

1. The diagram below shows a pruning method in coffee. Study it and answer that follow
   1. Identify the pruning method illustrated above
      
      • Single stem pruning (1x1=1mark)
   2. Explain how the pruning illustrated above is carried out
      
      • When young tree is 60-75cm tall, the first capping is done at height of 53cm.
      • Of the suckers that develop, the best growing one is selected and allowed to grow while all the other suckers are removed.
      • On attaining a height of 130cm, sucker is capped at 114cm.
      • Once again, the best growing sucker is selected and on growing to a height of 180cm, it is capped at 168cm.
      • Finally the single stem is allowed a bush of 150-180cm high (5 x ½ = 2 ½ marks)
   3. State three reasons for pruning in coffee
      
      • Regulate bearing,that avoid biennial bearing.
      • Remove old and unproductive branches.
      • Make harvesting easy by regulating the height of trees.
      • To open up the bush to allow for better air circulation.
      • Remove damp micro-climate that favor some pests like Antestia bugs and diseases like Coffee Berry Disease (CBD)
      • Open the plant facilitating the penetration of spray chemicals.
      • For economic use of chemicals (Any 3 x ½ = 1 ½ marks)
2. The diagrams below shows some storage pests. Study them and answer the questions that follow
   
   1. Identify the pests a, b and c
      
      1. True maize weevil (Sitophilus spp)
      2. Bean weevil / Bean bruchid
      3. Flour weevil (3x1 = 3 marks)
   2. State the kinds of damages they cause to the stored produce
      
      • Eat the produce reducing its quantity
      • Make holes on the produce reducing the quality
      • Themselves contaminate the produce reducing the quality (Any 2 x ½ = 1 mark)
   3. Two methods which can be used to control storage pests.
      • Dusting of the produce with the appropriate chemicals
      • Early / Timely harvesting of the produce
      • Proper drying of the produce.
      • Cleaning and dusting the store before storage of the produce using the appropriate chemicals. (Any 2 x ½ = 1 mark)
3. The diagram below shows two different weeds x and K. study them and answer the questions that follow
   1. Identify the weeds x and K.
      • X – Pigweed (Amaranthus hybridus/spp)
      • K – Thorn apple (Datura stramonium) (2 x1 = 2 marks)
   2. On basis of plant morphology identify the class of weed x
      
      • Broad leaved weed (1 x1 = 1 mark)
   3. Give one disadvantage of weed k
      
      • Is a poisonous weed (1 x 1 = 1mark)
   4. Give one beneficial use of weed x
      
      • Used as a vegetable
      • Used to feed livestock (1 x 1 = 1 mark)
4. Below is a diagram of a compost pit. Study it and answer the questions that follow
   
   1. Identify the layers A, B, C, D and E
      • A – Garden top soil
      • B – Wood ash
      • C – Well rotten organic manure
      • D – Grass, leaves, refuse
      • E – Maize stalks (5 x ½ = 2 ½ marks)
   2. State two important reasons of layer B
      • Wood ash improves the levels of Potassium and Phosphorous.
      • Modifies the pH which enhances microbial activity / raises the soil pH. (2x ½ = 1 mark)
   3. State the functions of the stick and the grass cover
      
      • Stick – Helps to check on the temperature within the compost and the level of the decomposition.
      • Dry grass cover provides a cover that keeps off rain water (2x ½ = 1 mark)
   4. Name the other method of making compost manure
      
      • Heap system (1 x ½ = ½ mark)

Section C: (40Marks)

1.  
   1. Describe the risks and uncertainities encountered by wheat farmers in Kenya.
      • Fluctuation of commodity prices
      • Physical yield uncertainities where the farmer does not know how much to expect
      • Ownership uncertainity- farmers lose the produce through theft, fire, death of changes of government policy
      • Outbreak of pests and diseases which affect the expected outcome
      • Sickness and injury uncertainty-farmers affected lose to work due to sickness and injury
      • New production technique uncertainty-farmer may not be certain to whether a new technology is as effective as the previous one/Farmers investing in machinery which may become outdated within a short time
      • Natural catasrophies-floods, drought, earthquekes, storms and strong wind may destroy the crops. (7 x 1 = 7 marks)
   2. State the importance of Agroforestry (7mks)
      
      • Source of energy
      • It provides fruits
      • It provides fodder for livestock
      • Provides aesthetic value
      • Provides shelter to animals and crops
      • Farmers generate income from the sale of poles, timber and fruits.
      • Helps in soil and water conservation.
      • Trees help to balance the amount of Carbon (iv) oxide in the atmosphere.
      • Trees serve as windbreaks.
      • Trees demarcate / mark boundaries (Any 7x1 = 7 marks)
   3. Outline Six factors that affect rooting of cuttings
      
      • Temperature
      • Relative humidity
      • Light intensity
      • Oxygen supply
      • Moisture supply
      • Chemical treatment
      • Leaf area (Any 6x1 = 6 marks)
2.  
   1. Discuss the influences of soil structure on crop production.
      • Drainage – Should facilitate good drainage therefore avoid water logging which is unsuitable for most crops.
      • Water penetration / infiltration-It should ensure adequate water infiltration and retention for proper crop growth.
      • Aeration – It should be well aerated for proper root growth and enhanced microbial activities.
        Soil erosion – Since soil water infiltration is good, there is no surface run-off erosion.
      • Leaching – It should resist excessive leaching of nutrients.
      • Land tillage – Proper soil structure facilitates easier land tillage / operations e. g ploughing, harrowing and subsoiling.
      • Microbial activities – Favorable conditions due to proper aeration are created for good microbial activities.
      • Heat transfer – The right amount of heat is transferred into the soil for proper germination and root development.
      • Germination – Seeds germinates well in proper structured soils (Any 7x1 = 7 marks)
   2. Outline six factors that influence price of a commodity or service
      
      • Number of sellers in the market
      • Price of related goods.
      • Level of technology
      • Weather / season
      • Government policy
      • Number of buyers in the market
      • Expected changes in prices
      • Cost of production
      • Increase or decrease of supply of associated goods
      • Nature/Level of transportation system (Any 7x1 = 7 marks)
   3. Explain six types of pesticides according to their mode of action
      • Stomach poisons – They kill when part of the plant sprayed with the chemical then eaten by the pests.
      • Systemic Poison – They are circulated to all parts of the pest once it has been eaten by it. Kill by inhibiting vital processes of the pests.
      • Anti-feedants – They inhibit feeding in pests thus starving them to death.
      • Contact poisons – They kill by absorption through the pest skin/exoskeleton. Are either sprayed to the crop or pests.
      • Repellant – They keep the pests away from the plants.
      • Suffocation /suffocants – kill by interfering with the breathing system of the pests. (6 x 1 = 6 marks)
3.  
   1. Describe the uses of farm accounts in the farm
      • Aids in negotiation for credit facilities
      • Helps in assessing the tax to pay to avoid over or under taxation
      • Provides means of comparison with other farms performance.
      • Shows the value of the farm.
      • Shows the financial position of the farm.
      • Reminds the farmer of his creditors and debtors.
      • Helps the farmer in selection and expansion of the enterprises.
      • Helps in evaluation of the farm assets and liabilities.
      • Helps the farmer in making sound management decisions.
      • Helps to determine whether the farm is running at a profit or loss.
      • Helps the farmer in preparing the budget. (Any 8x1 = 8 marks)
   2. Six advantages of using seeds for crop propagation
      • Seeds are easy to treat against soil borne pests and diseases
      • Seeds are easy to store since are not bulky.
      • Seeds are easy to handle making planting operations faster.
      • Its easier to use machines when planting seeds.
      • Manure and fertilizer can be easily mixed with seeds.
      • Seeds can be stored for long period of time.
      • It is possible to develop new crop varieties due to cross pollination. (Any 6 x1=6 marks)
   3. Discuss factors to consider when selecting implements to use for primary cultivation
      • Topography of the land – when land is too steep a jembe or fork or ox-plough is appropriate than a tractor drawn plough.
      • Condition of the land – fork jembe is more appropriate on land that is stony, stumpy and hard.
      • Depth of tillage required – when deep cultivation is required heavy tractor – drawn ploughs and subsoilers are more appropriate.
      • Soil type – Soils that are hard, heavy and difficult to work on e. g clay requires heavier implements than light soils.
      • Scale of production – It is more cost effective to use a tractor drawn implements on large scale piece of land than a small one.
      • Cost of implements –The high cost of certain implements may be prohibitive.
      • Capital available – Capital availability determines whether to purchase or hire implements or tools.
      • Skills / know-how – A tractor requires better skills to operate than a hand jembe.
      • Type of tilth required – Rotavator gives a fine tilth than a disc plough.
      • Time available – If time before onset of rains is limited, then it’s advisable to use a tractor and animal drawn implements than hand tools. (Any 6x1 = 6 marks)