The Union Public Service Commission has published the UPSC IFoS Syllabus 2026. The examination consists of three stages: Prelims, Mains, and an Interview. The Prelims include objective-type questions common with the IAS exam, while the Mains consist of descriptive papers. Final selection is based on performance in the Mains and the Interview.
Overview
| Particulars | Details |
|---|---|
| Exam Name | UPSC Indian Forest Service (IFoS) Exam |
| Organization | Union Public Service Commission |
| Post Name | Indian Forest Service |
| Selection Process | Prelims, Mains, Interview |
| Mode of Exam | Objective and Descriptive |
| Marking Scheme | Total of 1700 marks (Mains + Interview) |
| Website | https://upsc.gov.in |
Selection Process
- Prelims Examination
- Mains Examination
- Interview / Personality Test
Exam Pattern for Preliminary Examination
| Paper | Subject | Type | Marks | Duration | Qualifying Criteria | Negative Marking |
|---|---|---|---|---|---|---|
| Paper I | General Studies | Objective MCQ | 200 | 2 Hours | Counts for merit | 1/3rd |
| Paper II | CSAT | Objective MCQ | 200 | 2 Hours | Minimum 33% | 1/3rd |
Exam Pattern for Mains Examination
- Total Papers: 6 (All descriptive/essay-type)
- Paper I: General English – 300 marks
- Paper II: General Knowledge – 300 marks
- Papers III to VI: Two optional subjects (2 papers each, 200 marks per paper)
- Total Mains: 1400 marks
- Medium: English only
List of Optional Subjects
- Agriculture
- Agricultural Engineering
- Animal Husbandry & Veterinary Science
- Botany
- Chemistry
- Chemical Engineering
- Civil Engineering
- Forestry
- Geology
- Mathematics
- Mechanical Engineering
- Physics
- Statistics
- Zoology
Interview / Personality Test
The Interview carries 300 marks. It assesses mental calibre, intellectual qualities, social traits, interest in current affairs (especially forestry and environment), and suitability for the service. Final merit is prepared based on Mains (1400) + Interview (300) = 1700 marks.
Detailed Syllabus
General English (Paper I – 300 Marks)
- Essay Writing: Essay in English on given topics
- Comprehension: Questions to test understanding of passages
- English Usage: Grammar, vocabulary, précis writing, summary, sentence correction
General Knowledge (Paper II – 300 Marks)
- Current Events: National and international
- Indian Polity & Constitution: Political system, governance
- History of India: Major events and movements
- Geography of Nature: Physical, social & economic aspects
Agriculture
Agriculture Paper I
- Ecology & Environment: Relevance to man, natural resources, sustainable management, conservation, pollution hazards
- Cropping Patterns: Agro-climatic zones, multiple cropping, intercropping, package of practices for major crops
- Soil: Physical, chemical & biological properties, fertility, fertilizers, problem soils & reclamation
- Water Management: Irrigation, drainage, water-use efficiency, watershed management
- Farm Management & Extension: Economics, marketing, mechanization, extension programmes
Agriculture Paper II
- Cell Biology & Genetics: Cell theory, heredity, plant breeding, seed technology
- Plant Physiology: Photosynthesis, respiration, growth regulators
- Horticulture & Pests: Fruit & vegetable cultivation, preservation, diseases & pest management
- Food Production: Major crops, biotechnology applications
Agricultural Engineering
- Soil & Water Conservation: Techniques, planning, erosion control
- Irrigation & Drainage: Principles, engineering practices, water management
- Farm Machinery & Power: Mechanization, tools, energy sources
- Process Engineering: Post-harvest technology, processing techniques
Animal Husbandry & Veterinary Science
- Animal Nutrition: Requirements, diets, feeds
- Genetics & Breeding: Reproductive genetics, breeding programmes
- Health & Hygiene: Disease control, prevention, veterinary public health
- Dairy & Meat Technology: Processing, hygiene, products technology
Botany
- Plant Pathology: Microbiology, plant diseases
- Morphogenesis: Developmental biology of plants
- Genetics & Evolution: Molecular biology, genetic principles
- Ecology & Plant Geography: Plant-environment interactions
Chemistry
- Atomic Structure: Quantum models
- Chemical Bonding: Types, molecular orbital theory
- Thermodynamics: Laws, statistical applications
- Electrochemistry: Ionic equilibria, electrode processes
- Reaction Mechanisms: Kinetics, organic reactions
- Polymer Chemistry: Properties, synthesis
- Spectroscopy: Structure determination
Chemical Engineering
- Fluid & Particle Dynamics: Flow behaviour
- Heat & Mass Transfer: Conduction, convection, diffusion
- Thermodynamics Applications: In chemical engineering
- Environmental Engineering: Pollution control, waste management
Civil Engineering
- Mechanics & Materials: Structural analysis
- Fluid Mechanics: Hydraulics, fluid flow
- Construction Technology: Equipment, planning, management
- Environmental Engineering: Water supply, sanitation, pollution control
Forestry
Forestry Paper I
- Silviculture & Agroforestry: Techniques, systems, mangrove, social forestry
- Forest Soils & Watershed: Soil conservation, watershed management
- Environmental Conservation: Biodiversity, climate change
- Tree Improvement: Seed technology
Forestry Paper II
- Forest Management: Working plans, mensuration, remote sensing
- Forest Engineering & Survey: GIS, surveying
- Forest Resources & Utilization: Wood technology, NTFP
- Forest Protection & Wildlife: Pest control, wildlife biology
- Forest Economics & Legislation: Policies, Forest Conservation Act
Geology
- General Geology: Earth structure, processes
- Stratigraphy & Paleontology: Rock layers, fossils
- Mineralogy & Petrology: Minerals, rocks formation
- Economic & Mining Geology: Resources, extraction
Mathematics
- Linear Algebra: Matrices, vector spaces
- Calculus: Differential & integral
- Algebra & Analysis: Abstract algebra, real analysis
- Numerical Analysis: Computational methods
Mechanical Engineering
- Theory of Machines: Mechanisms, kinematics
- Manufacturing Science: Processes, techniques
- Thermodynamics: Thermal systems
- Heat Transfer: Refrigeration, air-conditioning
Physics
- Mechanics & Optics: Classical mechanics, physical optics
- Electricity & Magnetism: Electromagnetic principles
- Quantum Mechanics: Atomic physics
- Solid State Physics: Crystallography, materials
Statistics
- Probability: Theories, models
- Sampling: Theory & design
- Industrial Statistics: Production applications
- Optimization Techniques: Operations research
Zoology
- Non-Chordata & Chordata: Anatomy, classification
- Ecology & Ethology: Ecosystems, animal behaviour
- Genetics & Evolution: Heredity, evolutionary principles
- Biochemistry & Physiology: Cellular processes, systems
Preparation Strategy
- Visit the official website at https://upsc.gov.in to access the complete syllabus notification.
- Select your optional subjects based on your background and the approved list.
- Review past papers to understand the descriptive format of the Mains.
Important Links
| Particulars | Link |
|---|---|
| Official Website | https://upsc.gov.in |
Frequently Asked Questions (FAQs)
Q1. Where can I find the official UPSC IFoS Syllabus PDF for 2026?
Ans. You can download the complete syllabus PDF directly from the official UPSC website at upsc.gov.in.
Q2. Which subjects are covered in the IFoS examination?
Ans. The exam includes General English and General Knowledge in the Mains, plus two optional subjects you choose from a list that includes Agriculture, Forestry, Botany, Zoology, and various engineering disciplines. Prelims cover General Studies and CSAT.
Q3. How are marks distributed in the IFoS Mains?
Ans. The Mains stage is worth a total of 1400 marks. General English and General Knowledge carry 300 marks each, while the two optional subjects comprise four papers worth 200 marks each.
Q4. Does the Prelims exam have negative marking?
Ans. Yes, there is a penalty for incorrect answers in the Prelims. A deduction of 1/3rd of the assigned marks is applied for every wrong answer.
Q5. How much weight does the Interview carry?
Ans. The Interview, or Personality Test, is critical as it accounts for 300 marks. These marks are added to your Mains score (1400) to determine the final merit out of 1700 total marks.
Q6. Am I allowed to pick any optional subjects for the Mains?
Ans. You can choose two optional subjects from the official list provided by UPSC, which primarily includes science and engineering disciplines like Forestry, Mathematics, Physics, and Civil Engineering. Note that certain combinations may be restricted.
Q7. How long is each paper in the Mains exam?
Ans. Each of the six descriptive papers in the Mains examination is 3 hours long, making the total exam duration 18 hours across all papers.
