Introduction 

• Field practices are activities carried out on the field to facilitate proper growth and maximum yield of the various crops grown. 

They include the following: 

• Crop Rotation 

• Mulching 

• R0uting field practices

• Crop protection

• Harvesting  

Crop Rotation

• This is the growing of different types on the same piece of land in different seasons, in an orderly sequence. 

Importance of Crop Rotation 

• Maximizes use of nutrients and moisture. 

• Breaks the life cycle of pests and disease agents. 

• Maintains good soil structure. 

• Reduces soil erosion due to adequate soil cover. 

• Controls weeds that are specific to certain crops e.g. striga on cereals 

• Improves soil fertility when legumes are included in crop rotation. 

Factors Influencing Rotational Programme 

• Growth habits and nutrient req uirements. 

• Liability to soil erosion. 

• Crops attacked by the same pests and diseases should not follow one another in the programme. 

• Availability of capital and market for example beans or peas in legumes. 

Mulching 

• This is the placement of materials such as banana leaves or polythene sheets on the ground next to the growing crop. 

• These materials should not come into contact with the base of the crop as they may encourage pest attack. 

Importance of Mulching 

• Reduction of evaporation rate. 

• Smothers weeds. 

• Moderation of soil temperature. 

• Reduction of speed of run offs. 

Types of Mulching Materials 

• Organic mulching materials such as;

- Sawdust, wood shavings, coffee pulps, rice husks, 

- Dry grass, banana leaves, dry maize stalk, napier grass. 

• Inorganic or synthetic materials commonly used are either black or transparent polythene sheets. 

Advantages of Mulching 

• Prevents water evaporation thus maintaining moisture in the soil for crop use. 

• Acts as an insulator thus modifying the soil temperature. 

• It helps to control soil erosion. 

• It controls weeds by suppressing them. 

• After decomposition organic mulch add nutrients to the soil thus improving its fertility. 

• Humus produced after the decomposition of organic mulch improves soil structure and the water holding capacity of the soil. 

Disadvantages of Mulching 

• It is a fire risk. 

• Provides a breeding ground as well as a hiding place for pests that finally may attack the crops. 

• Traps the light showers of rainfall thus lowering the chances of rain drops reaching the soil. 

• It is expensive to acquire, transport and apply. 

Routine Field Practices 

Thinning 

• Removal of excess, weak, damaged or diseased seedlings. 

• Allows the remaining seedlings to get enough nutrients and moisture. 

• It is aimed at obtaining optimum plant population. 

Gapping 

• Filling the gaps so as to maintain proper plant population. 

• Gaps occur as a result of failure of seeds to germinate or dying of seedlings. 

• It should be done early enough for the seedlings to catch up with the other plants 

Rogueing 

• This is the removal and destruction of a diseased part of a plant or the whole plant. 

• The destruction can be achieved through burning of the uprooted plant. 

Pruning 

• Removal of extra unwanted parts of the plant. 

Reasons for pruning are: 

• To remove old, unproductive or diseased, damaged parts of the plant. 

• To train plants to take a desirable shape for example formative pruning in tea. 

• To control crop leave ratio hence avoiding overbearing. 

• To control diseases and pests for example antestia bugs in coffee. 

• To facilitate other operations such as spraying, picking and seeding. 

• To reduce wastage of chemicals applied on the crop. 

• To remove branches that  interfere with traffic, telephone lines and view. 

• Open up the plant to allow free air circulation and exposure of leaves to sunlight. 

       Note: Tools used are secateur, pruning saw and pruning knife. 

Earthing-up 

• This is the placement of soil in form of a heap around the base of the plant. 

• It is mostly carried out in tuber crops such as Irish and sweet potatoes to improve tuber formation. 

• It is also carried out in groundnuts and maize. 

• In groundnuts it promotes production of pods while in maize it provides support to prevent lodging. 

Crop Protection 

Weed Control 

• Weeds are plants growing where they are not wanted, that is a plant out of place. 

• Such plants include blackjack, couch grass, thorn apple and Mcdonald's eye. 

• Such plants should be eradicated or controlled using recommended methods. 

Pest Control 

• Crop pests are living organisms that are harmful to the crops. 

• They include; insects, nematodes, rodents, thrips and mites. 

• They cause great damage to crops in the field and stored produce. 

Control of Crop Diseases 

• A disease is any alteration in the state of an organism and functions of a plant or its parts. 

• Disease causing organisms are known as pathogens. 

• They include fungi, viruses and bacteria. 

• Diseases caused by fungi are referred to as fungal diseases while those caused by viruses and bacteria are referred to as viral and bacterial respectively. 

Harvesting 

• It is the gathering or of the farm produce after maturity. 

    Time of harvesting depends on: 

• Stage of maturity of the crops. 

• Use of the crop. 

• Tastes and preferences of consumers. 

• Weather conditions, hence liability to spoilage. 

• Moisture. 

Methods of harvesting is determined by: 

• Scale of farming for example large scale farming machines are used. 

• Type of crop for example pyrethrum is harvested by hand. 

• Uniformity in ripening of the crop for example wheat is harvested by use of combined harvester while coffee is harvested by hand. 

• Uniformity in height of the crop and size of seed, fruits and flowers. 

• Financial status of the farmer. 

• Part of the plant to be harvested. 

Post-Harvest Practices 

• These are the preparations carried out on crop produce before it gets to the consumer.  They include; 

• Threshing/shelling. 

• Drying. 

• Cleaning. 

• Sorting and grading. 

• Dusting. 

• Processing. 

• Packaging. 

Storage 

     Purpose of storage is to;

• Prevent spoilage 

• Make the produce available for future use 

• To await good market prices. 

Requirements for proper store are:  

• It should be clean. 

• It should be well ventilated. 

• It should be raised from the ground to prevent damp conditions. 

• It should be dry. 

• It should be strong to hold crop produce. 

• It should be easy to clean. 

• It should be vermin-proof. 

• It should be secure from theft. 

• It should be treated against pests such as weevils. 

Types of Storage 

• Traditional storage structures. 

• Modern storage structures. 

Preparation of the Store 

• Cleaning the store. 

• Maintenance 

• Dusting the store with appropriate chemicals. 

• Clearing the vegetation around the store to keep off vermin.