1. What is the main purpose of land preparation before planting crops?
To permanently stop all soil organisms from working
To remove weeds, loosen the soil and create a seedbed suitable for planting
To compact the soil so seeds stay on the surface
To increase the number of rocks on the surface
Explanation:
Good land preparation removes weeds, breaks clods and creates a fine seedbed so seeds can germinate and roots can grow.
2. When is the best time to prepare land for rain-fed crops in most parts of Kenya?
Shortly before the onset of the rains
During the coldest night of the year
After the crop has already emerged
In the middle of a long dry spell with no rain expected
Explanation:
Preparing land just before the rains ensures the seedbed has moisture for germination while reducing the time for weeds to re-establish.
3. Which hand tool is commonly used by smallholder farmers in Kenya for land preparation?
Combine harvester
Gas-powered tiller only
Mechanical rotavator often pulled by tractor
Jembe (hand hoe)
Explanation:
The jembe (hand hoe) is widely used by smallholder farmers for clearing, digging and shaping beds when tractors are not available.
4. Why is contour farming practiced on sloping land?
To ensure all water drains to the bottom of the slope
To encourage faster downhill water flow
To reduce soil erosion and slow runoff by following the slope contours
To make harvesting more difficult
Explanation:
Planting along contour lines helps slow water movement and reduces soil loss on slopes.
5. What depth of ploughing is generally recommended for crops like maize to allow good root growth?
Less than 2 cm
More than 1 metre
About 20 cm
Exactly 5 mm
Explanation:
Ploughing to about 20 cm loosens the root zone sufficiently for maize roots and improves drainage and aeration.
6. Why are ridges made for crops such as potatoes and sweet potatoes?
To improve drainage, allow root development and conserve moisture in the seedbed
To make the land unusable for other crops
To stop roots from forming
To increase wind speed over the crop
Explanation:
Ridges create space for tuber development, improve drainage and can help conserve moisture around roots.
7. What is the purpose of harrowing after primary ploughing?
To remove all organic matter permanently
To compact the surface for water runoff
To plant seeds deeper than ploughing can
To break clods, level the surface and create a finer seedbed
Explanation:
Harrowing smooths and refines the rough ploughed soil, making it suitable for planting and seed contact.
8. What does good soil tilth mean?
The soil is completely dry and hard
The soil has no nutrients at all
The soil is full of large rocks only
The soil is in the right physical condition for seed germination and root growth
Explanation:
Tilth describes the soil's structure and texture that allow roots to grow, hold water and let air reach roots.
9. How should perennial weeds and grasses be controlled before planting?
Plant immediately without any control so they grow with the crop
Cover them with plastic and leave without further action forever
Burn the whole field daily until planting
Remove or uproot them and, where practical, use deep ploughing or targeted herbicide before planting
Explanation:
Perennial weeds need thorough removal or control before planting to reduce competition and make crop establishment easier.
10. Why should excessive tillage be avoided?
It always increases soil fertility immediately
It guarantees no weeds will ever return
It makes soil taste better
It can destroy soil structure, increase erosion and reduce organic matter
Explanation:
Too much tillage breaks down soil aggregates, exposes organic matter to rapid decomposition and raises erosion risk.
11. Why is soil testing recommended before major land preparation and fertilizer use?
To measure how many worms there are to sell
To color the soil for aesthetic purposes
To determine existing soil fertility and what fertilizers or lime are needed
To see if the soil contains gold
Explanation:
Soil tests show nutrient levels and pH so farmers can apply the correct type and amount of fertilizer or lime.
12. When is cow or farmyard manure best added to the field during land preparation?
Added only to harvested grain
Incorporated into the soil a few weeks before planting
Left on the surface and then immediately set on fire
Mixed with pesticides and applied only after harvest
Explanation:
Incorporating manure before planting allows it to decompose, release nutrients and improve soil structure for seedlings.
13. What is conservation tillage (minimum tillage)?
A method to remove all residues and sterilize the soil
A system that reduces ploughing and leaves crop residues to protect the soil
Planting crops without any soil at all
Heavy tillage every day to make soil dust
Explanation:
Conservation tillage reduces soil disturbance and keeps residues on the surface to prevent erosion and conserve moisture.
14. Why is land leveling important for irrigation farming?
To ensure water spreads evenly across the field and prevent waterlogging
To make the field steeper for faster runoff
To stop irrigation completely
To create hills where water collects only in one spot
Explanation:
Level fields allow uniform water application, reducing dry spots and areas of waterlogging that damage crops.
15. What is the main benefit of building terraces on steep farmland?
They reduce soil erosion and allow cultivation of steep slopes
They make the land steeper and increase erosion
They are used only for aesthetic garden design
They prevent any plant from growing
Explanation:
Terraces slow water flow, trap soil and make steep slopes suitable for crop production.
16. Why is stumping and clearing necessary before cultivation in formerly forested land?
To remove roots and stumps that interfere with ploughing and root growth
To ensure pests hide under the stumps
To leave big stumps to block machinery
To encourage large trees to regrow quickly among the crops
Explanation:
Removing stumps and large roots is needed so implements can work the soil and crop roots are not obstructed.
17. What is a cover crop and why is it used during land preparation periods?
A crop planted only to be immediately harvested for timber
A crop that always kills the soil microbes
A material used to cover seeds so nothing grows
A crop like legumes planted to protect the soil, fix nitrogen and reduce erosion when the main crop is not growing
Explanation:
Cover crops protect the soil from erosion, improve fertility (especially legumes) and keep the soil active between main crops.
18. How does adding organic matter (compost or manure) help prepared land?
It makes the soil impermeable to water
It turns the soil into pure sand
It improves soil structure, increases water holding capacity and supplies nutrients
It reduces the number of beneficial microbes permanently
Explanation:
Organic matter enhances soil tilth, retains moisture, feeds soil organisms and slowly releases nutrients to crops.
19. What should a farmer do when preparing land that is swampy or waterlogged?
Drain excess water or use raised beds/ridges before planting
Cover the land with plastic and leave
Plant immediately without changing water levels
Add extra water to make it deeper
Explanation:
Excess water must be removed or crops raised on ridges to prevent root suffocation and promote healthy crop establishment.
20. Why are windbreaks or shelterbelts planted around fields during land preparation planning?
To attract more wind for drying the soil
To reduce wind speed, protect soil from wind erosion and protect crops
To make planting more difficult
To encourage birds to destroy the crop
Explanation:
Windbreaks lower wind speed across fields, reducing soil loss, drying and physical damage to crops.
21. What is a risk of deep ploughing when done too often on sloping land?
It turns slope into perfectly flat land instantly
It may expose more soil to erosion and reduce long-term soil stability
It permanently increases soil fertility without limits
It guarantees zero runoff forever
Explanation:
Frequent deep ploughing on slopes can break down protective layers and increase vulnerability to erosion.
22. Why is knowing the soil pH important during land preparation?
To know how many worms to add
To determine if lime is needed to correct acidity and to know nutrient availability
To choose the loudest farming tool
To decide what colour the soil will be
Explanation:
Soil pH affects nutrient availability; testing pH tells farmers if liming or other adjustments are necessary before planting.
23. What is the ideal soil moisture condition for tillage to avoid compaction?
Moist but not wet (firm with little soil sticking to tools)
Bone-dry and dusty
Soggy and waterlogged
Frozen solid
Explanation:
Tilling when soil is moist (not saturated) reduces compaction and clod formation; wet soil compacts and dry soil may be too hard.
24. Why should large stones and roots be removed during land preparation?
To prevent damage to planting tools and to allow easy root growth and uniform planting depth
To provide hiding places for pests near seedlings
To increase soil acidity
To make it harder to plant seeds
Explanation:
Removing stones and large roots protects implements, helps planting at the correct depth and allows roots to develop unimpeded.
25. What is the main purpose of land preparation before planting crops?
To delay planting until the rainy season is over
To compact the soil to prevent water infiltration
To create a favourable seedbed that helps seeds germinate and young plants grow
To remove all soil nutrients so fertiliser can be added later
Explanation:
Land preparation aims to produce a fine, well-drained, and weed-free seedbed that allows good seed-soil contact, germination and root development.
26. Which of the following is a primary tillage operation used in Kenyan farms to turn the soil?
Mouldboard plough
Ridging
Harrowing
Leveling with a rake
Explanation:
Primary tillage tools like the mouldboard plough cut and turn the soil deeply, breaking up the surface and burying residues, while harrowing and ridging are secondary operations.
27. Why is it important not to plough or till the soil when it is too wet?
Because wet soil increases natural soil fertility instantly
Because wet soil changes the soil pH to alkaline
Because wet soil compacts and forms clods that reduce aeration and root growth
Because wet soil makes weeds disappear permanently
Explanation:
Working wet soil leads to smearing and compaction; clods form and soil structure is damaged, harming aeration, infiltration and root development.
28. Which secondary tillage tool is commonly used to break clods and produce a fine seedbed in Kenya?
Cassava planter
Harrow
Irrigation pump
Combine harvester
Explanation:
Harrowing is a secondary tillage operation used to level the field, break clods and create a fine tilth suitable for seeding.
29. What is the main benefit of ridging for crops like potatoes and sweet potatoes?
It reduces the crop's exposure to sunlight
It improves root development, drainage and makes harvesting easier
It prevents seeds from germinating
It increases soil acidity drastically
Explanation:
Ridging forms raised beds that enhance drainage, loosen soil for tuber development and simplify harvesting for root crops.
30. Why should crop residues and weeds be incorporated or removed during land preparation?
To permanently sterilise the soil
To increase the soil's clay content
To reduce pest and disease carryover and improve seedbed conditions
To make the soil dry faster by removing organic matter
Explanation:
Removing or properly incorporating residues and weeds reduces pests and diseases and prevents competition with the crop, improving seedling establishment.
31. What does 'seedbed firmness' mean and why is it important?
Soil is rock-hard so seeds cannot be eaten by birds
Soil surface is firm enough for good seed-soil contact but not compacted, which helps uniform germination
Soil surface is covered entirely with mulch to prevent planting
Soil is extremely soft so water drains away instantly
Explanation:
A firm but not compacted seedbed ensures good contact between seed and soil moisture, promoting even germination and emergence.
32. Which practice helps control soil erosion on sloping farms in Kenya during land preparation?
Ploughing straight up and down steep slopes
Removing all vegetation permanently
Contour ploughing or terracing
Burning all crop residues each season
Explanation:
Contour ploughing and terracing reduce runoff and soil loss by following the land's contours and creating barriers that slow water flow.
33. What is the role of liming during land preparation on acidic soils?
To make the soil more acidic
To raise soil pH and improve nutrient availability
To kill all earthworms
To increase soil salinity
Explanation:
Lime neutralises soil acidity, improving nutrient availability and soil biological activity, which benefits crop growth.
34. Which of the following is a benefit of minimum tillage or conservation agriculture during land preparation?
It guarantees higher yields without any soil fertility management
It reduces soil erosion, improves soil moisture retention and builds organic matter over time
It completely removes all soil organic matter rapidly
It forces soils to become compacted to prevent root growth
Explanation:
Minimum tillage conserves soil structure and moisture, reduces erosion and helps accumulate organic matter, supporting long-term soil health.
35. When preparing land for planting, why is it advisable to carry out a soil test first?
To check if the soil changes colour in sunlight
To find out the number of earthworms only
To determine soil fertility and pH so fertiliser and lime needs can be planned
To see if the soil can be used for building houses
Explanation:
Soil testing provides information on nutrient levels and pH, allowing for correct fertiliser and lime recommendations and better crop planning.
36. What is fallowing and why might a Kenyan farmer use it during land preparation?
Leaving land unplanted for a season to restore soil fertility and break pest cycles
Tilling the land every week without planting
Flooding the field permanently to prevent weeds
Planting extra crops to increase pests
Explanation:
Fallowing allows soil organic matter and fertility to recover and interrupts pest and disease cycles before the next crop.
37. Which tool is commonly used by smallholder farmers in Kenya for shallow land preparation and weeding?
Combine harvester
Disc harrow pulled by tractor
Hand hoe
Rotary tiller tractor attachment
Explanation:
The hand hoe is widely used by smallholders for shallow cultivation, seedbed finishing and weeding due to low cost and versatility.
38. What is the effect of leaving the soil surface too loose after planting?
Higher soil fertility because nutrients evaporate
Permanent increase in soil pH
Better protection from weeds because seeds cannot reach the surface
Increased moisture loss and risk of soil crusting, harming germination
Explanation:
A loose surface allows rapid evaporation, can form a crust after heavy rain, and reduces seedling emergence; a firm seedbed is preferable.
39. Why is proper drainage considered during land preparation, especially in lowland areas of Kenya?
To attract more insects for pollination
To make the soil colder so seeds won't germinate
To prevent waterlogging which can suffocate roots and cause crop failure
To keep the soil permanently flooded for all crops
Explanation:
Good drainage prevents waterlogging that reduces oxygen availability to roots and increases disease risk, thus protecting crop health.
40. What is the difference between primary and secondary tillage?
Primary tillage breaks and turns soil deeply; secondary tillage refines and levels the seedbed
Primary tillage is done after planting; secondary tillage is done before harvesting
Primary tillage uses only hand tools; secondary tillage uses only tractors
Primary tillage removes all weeds permanently; secondary tillage irrigates the field
Explanation:
Primary tillage (e.g., ploughing) loosens and turns soil, while secondary tillage (e.g., harrowing, ridging) breaks clods and finishes the seedbed.
41. For small-seeded crops, how deep should seeds generally be placed during planting in a well-prepared seedbed?
Shallowly, usually no deeper than 2–3 centimetres, to ensure seedlings can emerge
Buried deeper than 20 centimetres to conserve moisture
Inserted into compacted subsoil layers
Placed on the soil surface without any soil cover
Explanation:
Small seeds need shallow placement so they can access light and easily emerge; depth varies by species but shallow placement is typical.
42. How does adding organic manure or compost during land preparation benefit the soil?
It converts clay to sand overnight
It makes the soil repel water permanently
It improves soil structure, water-holding capacity and supplies nutrients
It instantly sterilises the soil killing all microorganisms
Explanation:
Organic amendments increase soil organic matter, improve structure and moisture retention, and slowly release nutrients to crops.
43. Which practice during land preparation helps reduce nematode populations and some soil-borne diseases?
Putting synthetic paint on soil surface
Crop rotation and use of resistant varieties
Planting the same crop in the same place every season
Adding extra irrigation to increase soil moisture
Explanation:
Rotating crops and using resistant varieties break pest and disease cycles, reducing nematodes and other soil-borne problems.
44. Why should fields be cleared of previous crop stubble carefully rather than by burning?
Because burning destroys organic matter and soil organisms; careful clearing conserves soil health
Because burning makes the soil too nutritious
Because burning makes the soil white and unattractive
Because burning permanently increases rainfall
Explanation:
Burning removes valuable organic matter and beneficial organisms; incorporating or composting residues maintains soil fertility and structure.
45. What is a key indicator that a field is ready for planting after land preparation?
The soil is completely waterlogged and sticky
There are many large rocks on the surface and deep holes
The field is covered with tall weeds and volunteers
The seedbed is firm at the surface, free of large clods and reasonably level
Explanation:
A ready seedbed is firm enough for seed contact, free of clods that impede emergence, and level for uniform planting and moisture distribution.
46. Which land preparation method helps conserve moisture in dry areas of Kenya?
Removing all mulch and leaving soil bare
Continuously grazing livestock on the prepared field
Ploughing deeply every week
Making ridges and basins to collect and store rainwater
Explanation:
Ridges, basins and tied ridges capture and hold rainwater near plant roots, improving moisture availability in dry conditions.
47. Which action should be taken to reduce the risk of soil compaction during land preparation with machinery?
Drive repeatedly over the same wet spots to smooth them
Use only the smallest possible tractor regardless of field size
Avoid working with heavy machinery when soil is wet and use wide tyres or tracks
Increase tyre pressure to the maximum and work in wet fields
Explanation:
Working wet soils with heavy machinery causes compaction; using wide tyres/tracks and avoiding wet conditions reduces compaction risk.
48. What is the purpose of levelling a field during land preparation?
To make the field visually appealing only
To ensure uniform water distribution and ease of planting and harvesting
To concentrate water at one corner of the field
To increase the amount of topsoil removed
Explanation:
Levelling prevents waterlogging in low spots and ensures even irrigation, planting depth and easier crop management and harvesting.
49. How does incorporating green manure crops during land preparation improve the soil?
They add organic matter and nitrogen (if legumes), improving fertility and structure
They remove all minerals from the soil completely
They permanently dry out the soil and make it infertile
They turn the soil into pure sand
Explanation:
Green manures increase organic matter; leguminous green manures fix nitrogen, enriching soil fertility and improving structure when incorporated.
50. Which practice during land preparation helps reduce weed problems before planting?
Adding only chemical fertiliser without soil preparation
Planting immediately without any weed control
Covering the field with plastic permanently
Shallow cultivation or stale seedbed technique to encourage weeds to germinate then remove them
Explanation:
The stale seedbed technique encourages weed seeds to germinate so they can be removed before planting, reducing weed pressure on the crop.
51. Why is the timing of land preparation important in the Kenyan farming calendar?
Because late preparation guarantees more pests
Because timing has no impact on crop performance
Because preparing too early or too late can reduce moisture availability or delay planting and affect yields
Because preparing land only in the dry season ensures no rain will come
Explanation:
Good timing ensures seedbed moisture and sowing align with rains; too-early work can dry the seedbed and too-late work delays planting and lowers yields.