2017 Agriculture Paper 1
SECTION A (30 marks)
Answer all the questions in this section in the spaces provided.
1. Give four reasons for intercropping in crop production. (2 marks)
– Maximize utilization of Plant nutrients;
– Controls erosion through cover cropping;
– Nitrogen fixation when leguminous crops are involved
– Smothers weeds;
– Diversification;
– Improves soil structure;
2. State four characteristics of extensive farming system. (2 marks)
Low capital is investment;
Large pieces of land;
Low labour required;
Low levels of management;
Utilizes marginal area;
Low production per unit area
3. State four minimum tillage practices. (2 marks)
– Use of herbicides;
– Uprooting/slashing;
– Use of cash crops;
– Limiting cultivation to the point planting;
– Proper timing of cultivation;
– Mulching;
4. Give four reasons why burning of land is discouraged. (2 marks)
– Destroys soil organic matter;
– Kills soil living organisms;
– Destroys soil moisture;
– Destroys soil structure;
– Destroys plant nutrients;
– Causes mineral imbalances through ash accumulation;
5. State four functions of Young Farmers’ Clubs. (2 marks)
– Participation in ASK shows;
– Involvement in agricultural projects at club level;
– Participation in young farmers clubs;
– Participation in animal rallies;
– Involvement in seminars and workshops related to agriculture;
– Participating in national tree planting activities;
– Participation in national ploughing contests;
– Participation in exchange programmes;
6. Distinguish between a perfect and an imperfect market. (1 mark)
– Perfect market:- Is where a buyer can purchase from any seller and vice versa.
– Imperfect market:- Is where some buyers and sellers are not aware of prices offered by other sellers;
7. State four reasons for practising intensive hedgerow agroforestry. (2 marks)
-Leguminous shrubs are included to fix nitrogen into the soil;
-Maximizes utilization of available land;
– Controls soil erosion;
– Suppresses weeds;
– Provides green manure;
– Source of fodder for livestock;
8. State four management practices in intensive hedgerow agroforestry. (2 marks)
-Establishment;
Cutting back;
– Management during dry season;
– Choice of appropriate tree species;
– Protection;
– Weeding;
– Fertilizer application;
9. State the meaning of each of the following terms as used
(a) crop rotation
– Is the growing of different types of crops or crops of different families on the same piece of land in an orderly sequence;
(b) pruning
– Removal of extra or unwanted parts of a plant;
(c) rogueing.
– Is the uprooting and destruction of plants infected by disease to prevent spread of the disease to healthy plants;
10. State four factors that determine the depth of planting.
– Soil moisture content;
– Size of planting material;
– Soil type;
– Type of germination;
11. State four disadvantages of broadcasting seeds during planting.
– Requires high seed rate;
Difficult to carry out crop management practices;
Operations cannot be mechanized;
Difficult to establish plant population;
– Uneven crop establishment;
12. State four characteristics of a good site for a nursery bed.
– Near a reliable water source;
– Well drained area with deep fertile soils;
– Gently sloping area;
– Secure area;- Sheltered area;
– Should not have been used for the same crop species in the previous season;
13. Name four types of market structures in agricultural marketing.
– Monopoly;
– Oligopoly;
– Monopsony;
– Perfect market
14. Name one crop that is propagated by each of the following:
(a) stem tuber– Irish potatoes
(b) split– Pyrethrum;
(c) slip– Pineapple
(d) bulbil.– Sisal
15. State four advantages of using certified seeds.
– Free from pests, weed and diseases;
– Has high germination percentage;
– Is clean;
– High yielding;
– Adapted to local ecological conditions;
SECTION B (20 marks)
Answer all the questions in this section in the space provided.
16. The diagram below illustrates water storage structures.
(a) Identify the structure labelled E. (l mark)
– Weir
b) Give two reasons why farmers prefer structure F to E. (2 marks)
– Water levels regulated;
– Controls flooding;
– Stores large volume of water;
– Can be used to generate HEP
(c) State two maintenance practices for the structure labelled F. (2 marks)
– Desilting;
– Remove trees and bushes from wall to prevent cracks and water seepage;
– Repairing broken/worn out parts
17. A farmer has a piece of land on which he can grow maize, cabbages and beans. The expected yields and selling prices of the three crops are shown below.
If the cost of producing any of the three crops is the same
(a) Which crop should the farmer grow? Show your working. (2 marks)
– Maize — 4 000 x 40 = 160 000
– Cabbages — 2 800 x 60 = 168 00
– Beans — 3000 x 80 = 240 000;
The farmer should grow beans;
(b) (i) State the farmer’s opportunity cost. ( l mark)
– Cabbages (168, 0001=);
(ii) Give a reason for your answer in (b) (i) above. (1 mark)
– Is the best alternative forgone;
(c) Give a reason why farmers always have to make a choice on the enterprise to implement on the farm. (1 mark)
– Resources are limited while possible enterprises are unlimited;
18. The following is a list of plant nutrients:
Copper, calcium, nitrogen, molybdenum, zinc, phosphorous, carbon, sulphur, iron and magnesium.
(a) Which one of the above plant nutrients is mainly known for
(i) promoting root development (l mark)
– Phosphorus;
(ii) preventing blossom end rot disease (1 mark)
– Calcium;
(iii) Strengthening plant stalks to prevent lodging. (l mark)
– Calcium;
(b) Name two forms in which nitrogen is absorbed from the soil by plants. (2 marks)
-Nitrate ions (NO3);
-Ammonium ions (NH4+);
19. A farmer is advised to apply 60 kg N, 20 kg P205 and 30 kg K20 per hectare. Calculate the quantity of urea (46% N), single super phosphate (20% P205) and muriate of potash (50% K20) the farmer should apply on his l0 hectares land. (5 marks)
60 kg N 20 kg P205 30 kg K 20 Land size = 10 ha
i) Urea = 46kgN — 100kg Urea;
= 60 x100/46 x 10 ha;
= 1304.305 kg of urea;
ii) SSP (20% P205 ) 20 kgN — 100kg Urea =20 x100/20 x 10 ha = 1000 kg of SSP;
iii) Muriate of Potash (50% K2O) 50 kg K2O — 100kg
Muriate Potash =30 x100/50 x 10 ha = 60 kg/ha
= 60 x 10 = 600 Muriate of Potash;
SECTION c (40 marks)
20.(a) Describe eight methods used in water harvesting. (8 marks)
– uses of dams
– Use of weirs;
– Use of ponds;
– Roof catchment;
– Wells;
– Rock catchment;
– Micro catchments;
– Retention ditches.
(b). Describe nine Ways in which biotic factors influence agricultural production. (9 marks)
– Transmit diseases;
– Feed on whole or parts of plants;
– Injure plants providing entry for secondary infection agents;
– Suck blood from animals causing anemia;
– Act on plant and animal remains to form humus;
– Some cause diseases;
– Some kill and feed other animals;
– Some bring out cross pollination;
– Some fix nitrogen into the soil;
– Increases cost of product through control measures;
(c). Describe the preparation of green manure. (3 marks)
– Plant the crop in the field;
– Allow the crop to grow up to the flowering stage;
– Plough the crop into the soil;
– Allow the crop to decompose before planting
21.(a) Describe seven harmful effects of crop pests. (7 marks)
-Transmit crop diseases;
– Feed on whole or parts of plants;
– Some unearth planted seeds;
– Deprive the plant of food sucking sap;
– Lower the quality of flowers, fruits and berries;
– Eat growing points of plants causing retarded growth;
– Feed on whole or parts of seeds and lower germination per-centage;
– Lower the yield expected;
– Cause wilting of plants by feeding on the roots;
– Reduce the surface area for photosynthesis by feeding on leaves;
– Chemical pest control measures affect the environment
(b). Describe eight safety measures a farmer should observe when using herbicides to control weeds. (8 marks)
– Read and follow manufacturer’s instructions;
– Wear protective clothing;
– Avoid inhaling the herbicide/not spraying against the wind/ wearing breathing masks/not smoking.
– Avoid eating before bathing;
– Bath thoroughly after handling herbicides;
– Avoid blowing — sucking blocked nozzles;
– Avoid herbicide drift to unintended crops and plants;
– Avoid contamination of animal feeds and water;
– Left, overs and empty containers should be properly dis-posed and not thrown in gardens bushes or pastures;
– Equipment used should not be washed in water sources used by animals and humans;
– Store the chemicals safely out of reach of children and away from food;
-Thoroughly wash the equipment used
(c). Describe the harvesting of coffee. (5 marks)
– Ripe cherries are picked by hand;
– Harvested cherries are spread on mats and sorted to remove unripe, diseased, dry and damaged berries;
– The diseased and overripe cherries are taken to factories as grade II;
– Good quality cherries are taken to the factory as grade I;
– Unripe, dry and undersized cherries are dried at home to form Butii which is taken to the factory at the end of the harvesting season
22.(a) Give five reasons why early defoliation is discouraged in pasture utilisation. (5 marks)
– High moisture content;
– Low dry matter content;
– Low crude protein yield;
– Low digestible nutrients;
– Leads to gradual weakening of the stand;
(b) Described five field management practices for onions. (5 marks)
– Thinning;
– Weeding;
– Top dressing;
– Pest control;
– Disease control.
(c) State five disadvantages of communal land tenure system. (5 marks)
– Lacks incentive for land development;
– Low yields due to overstocking;
– Poor stock breeding programmes;
– Difficult to control pests, parasites and diseases;
– Soil erosion is common;
– Lowers the carrying capacity of the land;
(d) State five characteristics of variable inputs. (5 marks)
– Quantity required varies with the level of production in a given time;
– Are added to fixed inputs for production;
– Cost value depends on the quantity used;>
– They are allocated to specific enterprises;
– Their cost value is used to calculate the gross margin of the enterprise;
