1. Give three factors that determine depth of ploughing during land preparation
-Crop to be planted
-Implement available
2. List four reasons for cultivating land before planting
- To improve soil aeration.
- Destroy weeds.
- To improve germination.
- Incorporate organic matter in the soil.
- Increase water infiltration.
3. (a) What is minimum tillage?-
Is a situation in which least possible cultivation operations are carried out in crop production.
(b) Give four farming practices that help in achieving minimum tillage.
- Clearing the land / bush clearing.
- Using appropriate chemicals to kill the existing vegetation.
- Weeding using herbicides.
- Planting / drilling seeds directly into the stubble of previous crop.
4. (a) Describe the establishment of grass pasture from the time the land is ploughed using a mould board plough to the time the pasture is ready for grazing
- Harrow the land to a fine filth;
- Harrow during the dry or before the rains;
- Make the seed be weed – free / ensure clean seed bed;
- Firm the seed bed using rollers after sowing;
- Select a desirable variety of seed for the ecological zone,
- Sow seeds at the onset rains/ early planting;
- Apply phosphatic fertilizers at appropriate rate of 200 – 300 kgs/ ha at planting time;
- Drill or broadcast the seeds evenly;
- Use a recommended seed rate for the variety / seed rate of 1.5 – 2.0 kh/ha pure seeds;
- Bury seeds at 2 ½ times their diameter; - Control weeds by uprooting/ apply a suitable herbicide; - Apply nitrogenous fertilizers about 6 weeks after germination in split application.
- Avoid grazing when the pasture is too young.
- Practice light grazing in the field phase of pasture establishment.
(b) Explain five practices that a farmer should carry out to ensure uniform germination of seeds
- Select seeds of the same size, variety, age and free from pests and diseases.
- Plant seeds at the same time.
- Prepare the whole field to required uniform tilth.
- Plant at the right moisture content of the soil / irrigation uniformly.
- Treat seeds before planting i.e. break dormancy.
- Plant at the correct depth.
(c) Describe five factors that determine the number of cultivations when preparing a seedbed
- Soil moisture content.
- Type of soil.
- Cost of operation.
- Size of seed/ type of planting material/ type of crop.
- Type of machinery available / use of tractors.
- Topography / gradient of the land/ liability of soil erosion.
- Skills of the operator.
- Initial conditions of the land/ the cropping history of the land.
- Time available to carry out the operation before planting.
5. State four physical conditions of the seedbed that need to be changed to facilitate germination
-Size of soil clods (clods (made small or medium size
-Appropriate soil depth
Soil looseness
Should be weed free
6. State four importance of sub soiling as a tertiary operation-
- Ensures better root penetration
-Brings leached nutrients to the surface
-Breaks hard pans Promotes aeration of the soil Promotes water infiltration
- Soil moisture content improved
7. Outline four advantages of rolling in seedbed preparation
-Press the seeds against the soil moisture Controls soil erosion
-Ensure uniform germination
-Controls removal of small seeds by wind
-Breaks large soil cods
8. State four disadvantages of minimum tillage
-The less porous surface increased soil erosion especially in heavily sols
-Difficulty in weed control Speed of planting to reduce due to large amount of residues in the soil and big clods
-Leads to accumulating of soil borne pests and diseases
9. The diagram below illustrates a tertiary operation carried out in the farm
a) Identify the tertiary operation
- Ridging
b) (i) State the importance of the tertiary operation identified in 20(a) above
-Encourage tuber expansion
-Allow easy harvesting of crop roots
(ii) Give two other tertiary operations carried out in the field besides the one identified above
-Rolling
-Levelling
10. Give two reasons why it is advisable to cultivate the field during the dry season
-Leads to timely planting
-Weeds are appropriately controlled especially the perennial such as couch grass
-Farmers take advantage of availability of labour reducing the cost of labour Control of soil borne pests
-Gives time for better organic decomposition 1
11. How are hard pans caused by cultivation?
- By repeated cultivation at the same depth;
- Cultivating the soil when wet using heavy machinery;
12. Give four factors that determine the number of secondary cultivation operations
- Type and size of planting material;
- Topography/slope f land;
- Soil moisture content;
- (Initial) condition of land/amount of vegetation on the land;
-Capital available
- Type of implement used;
13. Define the term minimum tillage
-It is the least number of cultivation operations either during preparation of the seed bed or during the management of the crops.
14. State any two factors that determine the number of cultivations on a field before it is ready for planting
-purpose of crop
-Prevalence of pests and diseases
-Prevalence of weeds
-concentration of desired chemical weather
-market demand
15. Give three benefits of timely planting of annual crops
- Enables crop to benefit maximumly from available moisture
-Crops make use of nitrogen flush available at that time
-Crops fetch high market prices
-Crops escape from pests and diseases
-There is high vigour in crops that resist diseases
-Ensures timely harvesting
16. State four factors determining the depth of ploughing land
- type of crop to be planted
-Implements available
-Type of soil
-Climatic conditions