Grade 10 Agriculture Study Notes

Settlement Through Government Programmes

After independence, many Kenyans had no land. The government launched settlement programmes — organised plans to provide land to citizens to encourage farming, support economic growth, and improve national food security.

How settlement supports food security

When citizens receive land through settlement, they begin farming straight away — producing food for their families and for sale. More farms in production means more food available nationally. This is the direct link between settlement programmes and national food security.

Key features of settlement programmes

• Land is provided free or at a reduced cost
• The programme decides how much land each person receives
• Citizens can begin farming and building livelihoods immediately

Land Adjudication

Sometimes people have farmed land for many years without any formal proof of ownership. Land adjudication is the legal process that fixes this — formally establishing and recording who owns the land.

The four steps of adjudication

1. Verifying claims — who says they own the land and on what grounds
2. Establishing history — how long the person or family has used the land
3. Determining boundaries — the exact edges of the piece of land
4. Registering ownership — recording the owner's name in official land records

After adjudication, the owner holds legal documents confirming their right to the land.

Welcome to Crop Production

This strand follows the full journey of crop farming — from choosing and preparing land, through growing and caring for crops, all the way to harvesting.

The strand covers seven sub-strands:

• 1.1 Agricultural Land — accessing land, its usefulness, its productivity, and why ownership security matters
• 1.2 Properties of Soil — what soil is made of and how it affects crops
• 1.3 Land Preparation — clearing, tilling and making a seedbed
• 1.4 Field Management Practices — pruning, top dressing and other crop care
• 1.5 Growing Selected Crops — nursery beds, transplanting and establishment
• 1.6 Crop Protection — identifying and controlling weeds
• 1.7 General Crop Harvesting — harvesting cereals and tubers

Land is where farming starts. Without productive, secure land, none of the other practices in this strand can succeed.

Introduction to Agricultural Land

Agricultural land is land used or set aside for farming — growing crops and rearing animals. It is the most basic resource a farmer needs. It provides space for crops and holds the soil that supplies plants with nutrients.

This sub-strand answers four key questions:

1. How do farmers access or own land for agricultural use?
2. What makes a piece of land useful (its utility) for farming?
3. What natural factors make land productive?
4. Why does secure ownership of land matter?

Leasing Land

Leasing land is a temporary way of using land you do not own. The farmer rents it from the owner for an agreed period and pays rent.

How leasing works

Before farming begins, both parties sign an agreement that states:

• How long the lease lasts
• How much rent is paid and when
• Any conditions on how the land is used

Leasing allows a person without land to start farming. However, because the arrangement is temporary, the farmer cannot make long-term investments — such as planting fruit trees — since they may have to leave before the investment pays off.

Example: In Kenya, leasing is common where family land is scarce or where a farmer wants to expand production beyond their own plot.

Allocation of Land by Government

Government allocation is different from settlement. Here, the government grants citizens the right to use public land — land belonging to the state — for agricultural purposes. The goal is to bring unused public land into productive use.

Conditions of allocation

Allocation is done on predetermined conditions:

• The size of land to be given
• The land rates (fees) to be paid
• The duration — how long the right to use it lasts

Note: Government allocation may not result in permanent ownership — the rights last only for the duration specified in the allocation terms.

Purchase of Land

Purchasing land means buying it from the current owner. Once paid, the owner formally transfers ownership to the buyer through a legal process.

Why purchase is the most secure form of ownership

Purchase is considered the most secure way to own land because:

• The buyer chooses the location they want
• The buyer negotiates the terms directly with the seller
• The buyer receives official ownership documents after purchase

The most important ownership document is a title deed — official proof that names the owner and defines the land boundaries. Owning a title deed means the farmer can plan long-term and use the land as security (collateral) when borrowing money from a bank.

Inheritance

Inheritance — also called succession — means receiving land from parents or relatives when they pass on or choose to transfer it.

How inheritance works in Kenya

Many Kenyan families pass down ancestral land in one of two ways:

• Through traditional customs of the community
• Through a legal transfer at the land registry

Where multiple heirs share a claim — for example, several children — they must negotiate and agree on how to divide or use the land.

Inherited land gives permanent ownership, allowing the farmer to plan long-term. Inheritance is the most common way Kenyan smallholder families access their farming land.

Donated Land

Donated land is land that is given freely to someone without any payment. The giver transfers the land — or the right to use it — out of goodwill.

Who donates land?

• Relatives — such as a parent giving land to a child
• Friends
• Community leaders or organisations

Types of donation

• Full transfer of ownership — the recipient becomes the permanent legal owner
• Right to use the land — without full ownership being transferred

Because it relies on someone's goodwill, donation is not a common way to access land. The rights attached to donated land depend entirely on what the giver and recipient agree.

Key Points — Ways of Accessing Land

Factors Determining Utility of Land

Utility of land means the value or usefulness of a piece of land for a particular farming purpose. The same piece of land may be highly suitable for one enterprise and completely unsuitable for another.

Example: Stony, sloppy land may be better for beekeeping than for growing vegetables, because bees can forage across rough terrain while vegetable crops need deeper, workable soil.

The main factors determining the utility of land for agricultural enterprises are: legal and social factors, climate, parasite and disease pressure, accessibility, topography, water availability, and soil factors.

Accessibility of Land

Some land has low utility simply because it is difficult to reach. Poor roads or no roads at all create serious problems for farming:

• Tractors and machinery cannot be brought in — limiting mechanisation
• Farm produce cannot reach markets easily — reducing income
• Inputs like seeds and fertiliser cost more to deliver

Legal Factors and Social Environmental Factors

In some urban and peri-urban areas, local laws and by-laws prohibit rearing certain animals — such as cattle and pigs — because they are considered a nuisance to neighbouring households.

A farmer with land in such an area cannot use it for those enterprises, no matter how fertile the soil is. Legal restrictions directly lower the utility of the land for prohibited activities.

Topography of Land

Topography refers to the physical shape of the land — how flat or steep it is. Very steep or sloppy land has several limitations:

• It is difficult to operate tractors and other machinery safely
• Some forms of irrigation cannot be applied on very steep land
• Expensive earthworks — contours and bench terraces — are needed before crop farming can begin

Climate and Weather Conditions

Climate and weather conditions — including availability of rainfall, amount of rainfall, average temperatures and humidity — determine the type of crops and animals best suited to a piece of land.

Land in an area with reliable, well-distributed rainfall can support a wide range of crop and animal enterprises. Land in a dry area with low or unreliable rainfall has lower utility because fewer enterprises can succeed there without costly irrigation.

Water Availability

Reliable water greatly raises the utility of land. Where there is reliable rainfall, many crop and animal enterprises can be carried out. Where water sources such as rivers are nearby, or where the water table is high, utility is also high — farmers can irrigate and grow crops even in dry periods.

Land with no reliable water source depends entirely on seasonal rainfall, which limits the range of enterprises and the number of growing seasons per year.

Soil Factors

Several soil characteristics affect how useful a piece of land is for farming:

• Depth of soil — shallow soils restrict root growth and limit crop choice
• Texture and structure — affect movement of water, air and roots through the soil
• Nutrient content — determines how well crops will grow
• Soil drainage — waterlogged soils damage most crops
• Soil pH — most crops prefer a pH of 6 to 7.5

A farmer uses these soil characteristics to decide which crops to grow. Deep, nutrient-rich, well-drained soil at the right pH suits a wide range of crops. Shallow, poorly drained or very acidic soil limits crop choices significantly.

Parasite and Disease Attack

Some land is located close to forests containing wildlife. Such land tends to have a high prevalence of ticks and other disease-causing organisms.

This makes such land unsuitable for rearing exotic breeds of cattle, which have not developed resistance to local parasites and diseases and are therefore highly vulnerable. The presence of parasites and diseases lowers the utility of the land for those livestock enterprises.

Natural Factors Determining Productivity of Land

Productivity refers to how much a piece of land can actually produce. Even land with high utility can have low productivity if natural conditions are poor. The seven natural factors are: soil composition and fertility, climate, topography, water availability, biotic factors, wind and air quality, and altitude.

Soil Composition and Fertility

The type of soil is determined by the minerals it contains. Its fertility is determined by the nutrients available in it. Together they decide which crops can grow and what yields the farmer can expect.

• Rich, fertile soil → high productivity, strong crops, good yields
• Poor, nutrient-depleted soil → low productivity, weak crops, low yields

Climate

Temperature, sunlight and rainfall are the three climate elements that most directly affect land productivity:

• Temperature — controls whether crops survive and how fast they mature
• Sunlight — drives photosynthesis, the process by which plants make food
• Rainfall — provides the water plants need to grow

These elements also determine which crop varieties are suited to a given area.

Topography of Land

The shape of the land affects two things:

• Drainage — flat land holds moisture longer; steep land loses water and topsoil through runoff and erosion
• Irrigation options — some systems only work on flat or gently sloping ground

Availability of Water

Reliable water sources — rivers, lakes, dams — allow farmers to supplement rainfall, grow crops through dry spells, and increase the number of growing seasons. Land near water is generally more productive than land that depends entirely on rain.

Biotic Factors

Biotic factors are the living organisms that interact with the farm. They can either increase or decrease land productivity.

Biotic factors that increase productivity

• Pollinators — bees, butterflies and other insects transfer pollen between flowers, enabling fruit and seed crops to form
• Soil microorganisms — bacteria, fungi and earthworms break down organic matter and release nutrients for plants

Biotic factors that decrease productivity

• Pests — insects and rodents that damage or destroy crops
• Predators — animals that attack farm livestock
• Disease-causing organisms — fungi, bacteria and viruses that infect crops and animals

Wind and Air Quality

Strong winds reduce land productivity by:

• Physically damaging or flattening crops — breaking stems, tearing leaves
• Spreading animal diseases from one farm to another

Polluted air — near factories or busy roads — deposits harmful substances on soil and crops, making such areas unfavourable for farming.

Altitude

Altitude is height above sea level. Higher places are cooler; lower places are warmer. This directly affects which crops grow productively.

Security of Land Ownership

Security of land ownership means having a legal, stable right to use and develop land over the long term — most reliably through full ownership confirmed by a title deed.

What a farmer with secure ownership can do

• Make long-term plans — plant perennial crops and fruit trees, build fish ponds and other structures that require years to mature and pay off. These investments are only possible when the farmer is certain they will stay on the land.
• Borrow money — a title deed is accepted by banks as collateral (security) for a loan, giving the farmer capital for inputs, equipment or infrastructure
• Choose more enterprises — permanent ownership allows investment in costly, long-term developments like fish ponds and greenhouses that a short-term lessee cannot justify
• Protect the land — the farmer can build gabions and terraces to control erosion, knowing the benefit stays with them
• Use the land to earn more — a landowner can lease part of their land to others or use it as security to raise capital for other projects

Example: Jadeli owns land with a title deed. She plants avocado trees, builds a fish pond, constructs terraces and borrows from a bank using the deed as security. Sarai, who leases one acre for three years, grows vegetables and maize — sensible short-cycle crops she can harvest before the lease ends.

Introduction to Properties of Soil

Soil is the foundation of crop production. Not all soils are equal — the ability of a soil to support plant growth and sustain high yields depends on its composition and properties.

Ideal soil is balanced in four components: mineral particles, organic matter, water and air. In this sub-strand you will learn what each component does, how to test for them, and how the physical, chemical and biological properties of soil influence crops.

Soil properties are grouped into three categories:

• Physical properties — texture, structure, capillarity, porosity, water holding capacity, permeability
• Chemical properties — soil pH
• Biological properties — living organisms in the soil

Soil Water

Soil water is water held in the pore spaces of the soil above the water table. When it rains or when a field is irrigated, water enters the soil through large pores (macropores) and is stored in small pores (micropores).

Why soil water is important for crops

• Transports nutrients — dissolves and carries nitrogen, phosphorus, potassium and calcium to plant roots for absorption
• Required for photosynthesis — plants use water to produce food from sunlight
• Regulates soil temperature — water absorbs and releases heat slowly, moderating temperature fluctuations
• Supports soil microbes — bacteria and fungi need water to survive and to break down organic matter
• Aids soil formation (weathering) — water breaks down rock over time; areas with high rainfall have more weathered soils

Soil Mineral Particles

Soil mineral particles are inorganic particles that come from rocks. They make up most of the soil's volume and form its physical framework. They are grouped into three types by size:

• Sand — largest particles; feel gritty when rubbed between fingers
• Silt — medium particles; feel smooth and floury
• Clay — smallest particles; feel sticky

Mineral particles influence how water and air move through soil:

• Sandy soils have large pore spaces — water drains quickly but few nutrients are held
• Clay soils have small pores — they hold more water and nutrients. Clay particles have negatively charged surfaces that bind essential plant nutrients (a process called adsorption), making those nutrients available for uptake by plant roots

Soil Air

Soil air is the mixture of gases that fills soil pore spaces not occupied by water. It is constantly exchanged with the air above ground — a process called soil aeration.

Why soil air is important

• Provides oxygen for plant root respiration — when oxygen is lacking, plant growth slows or stops
• Supplies carbon dioxide used in photosynthesis
• Soil aeration removes excess carbon dioxide from the soil — high CO₂ levels harm roots
• Supports aerobic soil microorganisms — these organisms break down organic matter and release nutrients for plants

Note: The proportions of air and water in soil are inversely related — as water increases, air decreases, and vice versa. A proper balance between the two is needed for healthy crop growth.

Soil Organic Matter

Soil organic matter is made up of the partial or fully decomposed remains of living things — plants, animals, microorganisms — and humus (the stable, fully decomposed end product). It gives fertile topsoil its deep dark colour.

What organic matter is made of

• Living components — plant roots, earthworms, ants, bacteria, fungi
• Dead plant material — fallen leaves, dead roots, grass clippings
• Animal waste — manure from cattle, goats, poultry
• Decomposing material — partially broken-down residues
• Humus — the stable, well-decomposed fraction; too fine to be seen with the naked eye

What organic matter does for the soil

• Provides nutrients — releases them through decomposition for plants to absorb
• Improves soil structure — holds aggregates together, improving aeration, drainage and root penetration
• Increases water retention — acts like a sponge, storing and releasing moisture
• Buffers soil pH — neutralises excess acidity, preventing extreme pH swings
• Supports soil organisms — feeds bacteria, fungi and earthworms which in turn release more nutrients
• Influences soil temperature — dark topsoil absorbs heat during the day and loses it at night
• Acts as a carbon sink — stores carbon from the atmosphere, helping reduce the effects of climate change

Soil Sedimentation Test

The sedimentation test is used to separate and identify the mineral particles in a soil sample. When soil is shaken in water, the particles settle in layers — heaviest at the bottom, lightest at the top. This reveals the relative proportions of each particle type, which is used to determine soil texture.

Requirements

• 250 cm³ measuring cylinder
• Garden soil (about 50 g)
• Water (about 200 ml)
• Sodium hydrogen carbonate (baking soda, about 20 g) — to break up soil lumps

Procedure

1. Put about 50 g of garden soil into the measuring cylinder
2. Add about 200 ml of water
3. Add about 20 g of sodium hydrogen carbonate
4. Cover the mouth with your hand and shake vigorously for 2–3 minutes
5. Place the cylinder on a flat surface and allow contents to settle
6. Observe and record the distinct layers that form

What you observe

Distinct layers form with the heaviest particles at the bottom and the lightest at the top:

• Bottom layer — gravel (heaviest)
• Next — coarse sand
• Then — fine sand
• Then — silt
• Top layer — clay (lightest mineral particles)
• Floating on top — organic matter

Testing for Air in Soil

Soil contains air in its pore spaces. We can demonstrate this by adding water to a dry soil sample and observing what happens.

Procedure

1. Put a dry soil sample into a glass cylinder
2. Gently pour water from a second cylinder into the soil cylinder
3. Observe carefully

What you observe and why

When water is poured onto the soil, bubbles rise to the surface. This happens because water fills the pore spaces, forcing out the air that was trapped inside. The air escapes as visible bubbles.

Soil samples that produce more bubbles contain more air than those that produce fewer. This gives an indication of the relative air content of different soils.

Investigating Organic Matter in Soil

Organic matter is the part of soil made up of decomposed remains of once-living plants and animals. Darker soils typically contain more organic matter. We can demonstrate its presence by shaking soil in water — organic matter is less dense than mineral particles and floats to the top.

Simple test

1. Put a sample of fresh garden soil into a glass jar half-filled with water
2. Shake vigorously
3. Allow to settle and observe

The layer that floats at the top of the water is organic matter. Below it, mineral particles settle in layers by size (as in the sedimentation test).

Components of soil organic matter

• Living components — plant roots, earthworms, ants, bacteria, fungi
• Dead plant material — fallen leaves, dead roots, stems, grass clippings
• Animal waste — manure from cattle, goats, poultry
• Decomposing organic matter — partially broken-down plant and animal residues
• Humus — the stable, fully decomposed fraction that is most beneficial; too fine to see with the naked eye

Key Points — Soil Components

Testing for Water in Soil (Weighing Method)

Soil contains water in its pores. We can prove this — and measure how much — by heating a soil sample and comparing its weight before and after. Water evaporates when heated, making the soil lighter.

Requirements

• Bunsen burner, tripod stand and wire gauze
• Evaporating dish
• Stirring rod
• Weighing balance
• Dry garden soil sample

Procedure

1. Weigh an empty evaporating dish and record the weight (x g)
2. Add dry garden soil to the dish and weigh again
3. Heat the dish over the Bunsen burner at 100–105°C for about one hour, stirring occasionally to allow moisture to escape
4. Allow the dish to cool, then weigh again (z g)
5. Calculate the percentage of water that evaporated

Calculation

Weight of water evaporated = weight before heating − weight after heating

Percentage of water = (weight of water evaporated ÷ weight of dry soil before heating) × 100

Caution: Do not handle the hot evaporating dish with bare hands — use tongs or a cloth.