Natural and artificial regeneration
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The document discusses natural and artificial regeneration of forests. Natural regeneration refers to the natural process by which plants replace or re-establish themselves through seed dispersal or vegetative reproduction like coppicing. It depends on several factors like seed production, germination conditions, seedling establishment and survival. Artificial regeneration involves human intervention through methods like sowing, planting or other means to renew forest crops. The choice of species, site selection, nursery practices and planting methods are important considerations for artificial regeneration.
Natural and artificial regeneration
- 2. Regeneration is ‘the renewal of a forest crop by natural or artificial means’ REGENERATIONREGENERATIONREGENERATIONREGENERATION 2
- 4. Natural regeneration refers to the ‘ natural process by which plants replace or re- establish themselves ’ WHAT IS NATURAL REGENERATION?WHAT IS NATURAL REGENERATION?WHAT IS NATURAL REGENERATION?WHAT IS NATURAL REGENERATION? 4 TWO MAIN SOURCES: 1.From seed 2.From vegetative part TWO MAIN SOURCES: 1.From seed 2.From vegetative part
- 5. 5 NATURAL REGENERATION FROM SEEDNATURAL REGENERATION FROM SEED DEPENDS UPON:DEPENDS UPON: NATURAL REGENERATION FROM SEEDNATURAL REGENERATION FROM SEED DEPENDS UPON:DEPENDS UPON:
- 6. Natural regeneration from seed is the production of adequate quantities of fertile seed by the trees of the area. 1. Seed year 2. Age of trees 3. Size of crown 4. Climate 5. External factors 6 SEED PRODUCTIONSEED PRODUCTIONSEED PRODUCTIONSEED PRODUCTION THE PRODUCTION OF SEED DEPENDS UPONTHE PRODUCTION OF SEED DEPENDS UPON
- 7. 7 SEED YEARSEED YEAR A year in which a given species bear seed abundantly Species Interval in year between Moderate seed year Good seed year Shorea robusta 2 3-5 Terminalia tomentosa 2 3-4 Pinus wallichiana 2 2-3 Pinus roxburghii 3 4-5 Cedrus deodara 3 7-8 Abies pindrow 6 10 SIZE OF CROWNSIZE OF CROWN As a general rule, the bigger the crown, the larger the production of seed While selecting seed bearers for natural regeneration, middle-aged mature tree with well developed crown should be selected
- 8. In the hill the trees growing towards the lower limit of the altitudinal zone of their species produce more seeds than those growing towards the upper limit. Hot dry years are generally followed by heavy seed year on account of increase in photosynthesis. Heavy storms at the time of pollen dissemination reduced changes of good seed production 8 CLIMATECLIMATE EXTERNAL FACTORSEXTERNAL FACTORS Injury by fire Insect attack
- 9. The seed produced by the trees is dispersed by many agency. 1. By wind-Conifers, Casuarina, Dalbergia,etc. 2. Water -Teak, most mangrove species,etc 3. Gravity -Oaks,Aesculus,Juglans regia,etc 4. Birds -Mulberry,Trema,prunus,etc 5. Animals -Acacia arabica, prosopis juliflora,etc. 9 SEED DISPERSALSEED DISPERSALSEED DISPERSALSEED DISPERSAL
- 10. After dispersal, a lot of seed is destroyed by insects, birds and rodents. They deposited in soil. 1. Internal factors 2. External factors 10 GERMINATIONGERMINATIONGERMINATIONGERMINATION GERMINATION OF SEED DEPENDS UPONGERMINATION OF SEED DEPENDS UPON
- 11. 1. Permeability to water 2. Permeability to oxygen 3. Development of embryo 4. After-ripening 5. Viability 6. Size of seed 7. Germination capacity 8. Germination energy 9. plant percent 11 INTERNAL FACTORSINTERNAL FACTORSINTERNAL FACTORSINTERNAL FACTORS
- 12. 12 PERMEABILITY TO WATERERMEABILITY TO WATER Moisture is very essential for germination. If the seed has hard seed coat, it prevent moisture reaching the seed embryo and therefore prevents germination. PERMEABILITY TO OXYGENERMEABILITY TO OXYGEN Oxygen is necessary for germination. Factors which inhibits moisture reaching the seed, also prevent oxygen reaching it. DEVELOPMENT OF EMBRYODEVELOPMENT OF EMBRYO The embryo should be fully developed at the time of seed fall eg. Fraxinus floribunda
- 13. 13 AFTER-RIPENINGAFTER-RIPENING If the embryo is fully developed, seed, sometimes do not germinate because the embryo is not chemically ready for germination. Such seeds germinate after ripening E.g. Juniperus macropoda VIABILITYVIABILITY Potential capacity of a seed to germinate E.g. Under natural condition sal seeds remain viable for about a week. If monsoon is delayed most of the seeds that fall on dry ground and die
- 14. 14 SIZE OF SEEDSIZE OF SEED The Size of seed, affect natural regeneration because while very minute seeds are washed away with the rain water, very big seeds do not get properly covered by soil or humus and so do not germinate. Species Seeds/gm Abies pindrow 17 Cedrus deodara 9 Cupressus torulosa 240 Pinus roxburghii 9 P. wallichiana 16 Picea smithiana 63 Species Seeds Albizzia lebbeck 7400/kg A.procera 23/gm Gmelina arborea 1764/kg Dalbergia sissoo 53/gm Pterocarpus marsupium 1623/kg Toona ciliata 247/gm CONIFERSCONIFERS BROAD - LEAVEDBROAD - LEAVED
- 15. 1. Moisture 2. Air 3. Temperature 4. Light 5. Seed bed 15 EXTERNAL FACTORSEXTERNAL FACTORSEXTERNAL FACTORSEXTERNAL FACTORS
- 16. Establishment is defined as the development of a new crop, to a stage when young regeneration is considered safe from normal adverse influences such as frost, drought and weeds. 16 SEEDLING ESTABLISHMENTSEEDLING ESTABLISHMENTSEEDLING ESTABLISHMENTSEEDLING ESTABLISHMENT 1. Development of roots 2. Soil condition 3. Light 4. Climatic factors 5. Competing weed growth 6. Grazing, browsing and burning 7. Drip 8. Composition of the crop FACTORS AFFECTING ESTABLISHMENTFACTORS AFFECTING ESTABLISHMENT
- 17. Vegetative reproduction is defined as a sexual reproduction in plants from some part of the plant body. e.g., Of trees by coppice or root sucker or from root. 17 NATURAL REGENERATION FROMNATURAL REGENERATION FROM VEGETATIVE PARTVEGETATIVE PART NATURAL REGENERATION FROMNATURAL REGENERATION FROM VEGETATIVE PARTVEGETATIVE PART METHODS OF VEGETATIVE REPRODUCTIONMETHODS OF VEGETATIVE REPRODUCTION 1. Coppice 2. Root sucker
- 18. 18 Coppice shootCoppice shoot A shoot arising from an adventitious bud at the base of a woody plant that has been cut near the ground or burnt back NATURAL REGENERATION BY COPPICENATURAL REGENERATION BY COPPICENATURAL REGENERATION BY COPPICENATURAL REGENERATION BY COPPICE Obtained byObtained by
- 19. Species Age of trees Season of coppicing Height of stump and method of cutting it Rotation Silvicultural system 19 FACTORS AFFECTING NATURALFACTORS AFFECTING NATURAL REGENERATION BY COPPICEREGENERATION BY COPPICE FACTORS AFFECTING NATURALFACTORS AFFECTING NATURAL REGENERATION BY COPPICEREGENERATION BY COPPICE
- 20. The Controlling FactorsThe Controlling FactorsThe Controlling FactorsThe Controlling Factors 20
- 21. No seed, or seed of poor viability. Absence of fertile plants with viable seed Seed harvesting by ants and predation by other insects, birds and mammals Lack of fire Lack of pollinators Seasonal variations SEED SUPPLYSEED SUPPLYSEED SUPPLYSEED SUPPLY 21
- 22. Soil compaction Loss of topsoil Unstable site Salinity Lack of water holding capacity Poor aeration SOIL CONDITIONSOIL CONDITIONSOIL CONDITIONSOIL CONDITION 22
- 23. Competition from other trees species Competition from weeds: eg. Strobilanthes and Petalidium in Teak Parent plant allelopathy : eg Eucalyptus Fungal attack COMPETITIONCOMPETITIONCOMPETITIONCOMPETITION 23
- 24. Insects or other invertebrates: Caterpillars, crickets, beetles, mites, nematodes, and other invertebrates eat seeds and seedlings Stock: cattle, sheep, horses and goats Native wildlife: Deer, hares, Elephant and Bison PREDATION OF YOUNG PLANTSPREDATION OF YOUNG PLANTSPREDATION OF YOUNG PLANTSPREDATION OF YOUNG PLANTS 24
- 25. Fire, Flood, Wind, Drought, Temperature extremes (eg frosts) NATURAL HAZARDS AND CONTROLSNATURAL HAZARDS AND CONTROLSNATURAL HAZARDS AND CONTROLSNATURAL HAZARDS AND CONTROLS 25
- 26. Natural RegenerationNatural RegenerationNatural RegenerationNatural Regeneration Preservation of locally adapted populations Preservation of high genetic variability Good adaptation to micro-sites Undisturbed root development Mostly low cost Low investment risk 26 AdvantagesAdvantages
- 27. Natural RegenerationNatural RegenerationNatural RegenerationNatural Regeneration Inability to change genetic stock Irregular regeneration density and tree species composition Dependence on fructification and seed production Low flexibility High management intensity and complexity Long risk period 27 DisadvantagesDisadvantages
- 29. Artificial regeneration is defined as ‘ the renewal of a forest crop by sowing, planting or other artificial methods ’ 29 WHAT ISWHAT IS ARTIFICIALARTIFICIAL REGENERATION?REGENERATION?WHAT ISWHAT IS ARTIFICIALARTIFICIAL REGENERATION?REGENERATION?
- 30. Reforestation: Restocking of a felled or otherwise cleared woodland by Artificial means Afforestation: Establishment of a forest by Artificial means on an area from which forest vegetation has always long bean absent 30 ObjectsObjectsObjectsObjects
- 31. 31 ESSENTIAL PRELIMINARY CONSIDERATIONESSENTIAL PRELIMINARY CONSIDERATIONESSENTIAL PRELIMINARY CONSIDERATIONESSENTIAL PRELIMINARY CONSIDERATION
- 32. Spp. to be raised are already known Spp. With particular use Local vegetation is the best indicator 32 SITE SELECTIONSITE SELECTIONSITE SELECTIONSITE SELECTION
- 33. Climate and micro – climate Soil conditions Stages of succession Object of management Consumers requirement Growth rate Availability of suitable exotic Ease of establishment Cost Effect on site 33 CHOICE OF SPECIESCHOICE OF SPECIESCHOICE OF SPECIESCHOICE OF SPECIES
- 34. 34 NURSERY PRACTICES USED TO INFLUENCENURSERY PRACTICES USED TO INFLUENCE SEEDLING QUALITYSEEDLING QUALITY NURSERY PRACTICES USED TO INFLUENCENURSERY PRACTICES USED TO INFLUENCE SEEDLING QUALITYSEEDLING QUALITY Seed source Seedbed density Control insects and disease Control competition Irrigate and fertilize Inoculate with mycorrhizae Top prune
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- 36. 36 Clonal origin seed origin
- 37. PRODUCTION OF QUALITY SEEDLINGS
- 38. PLACE DURATION Mist chamber 3o days Shade house 20-30 days Open hardening area 30 days Total 80-90 days PRODUCTION OF QUALITY SEEDLINGS
- 39. Sowing seeds (Broad-cast sowing, Line sowing, Stripe sowing, Patch sowing, Dibbling) Seedlings Cutting 39 CHOICE OF METHOD OF ARTIFICIAL REGENERATIONCHOICE OF METHOD OF ARTIFICIAL REGENERATIONCHOICE OF METHOD OF ARTIFICIAL REGENERATIONCHOICE OF METHOD OF ARTIFICIAL REGENERATION TYPE OF PLANTING ADVANTAGE DISADVANTAGE SOWING Less cost, easy work Large quantity of seed is required, Seedling mortality is high PLANTING Less material is required, less damage by animals Planting is costlier, requires more labour
- 40. 40 SpacingSpacing Spacing is varies with sp to sp Factors governing spacingFactors governing spacing Rate of growth Habit of branching No of annual rings/centimeter Height of planting material Site factors Inter-cultivation Market for small-sized timber Fruit production as objective Cost
- 41. 41 Arrangement of staff and labourArrangement of staff and labour Mechanization Soil preparation (Ploughing, Harrowing,Ridging) Digging pits for fence posts Transport Fire protection
- 42. • CUTTINGS • GRAFTING • BUDDING • LAYERING 42 Vegetative propagationVegetative propagation Any portion removed from the parent plant An art of joining parts of plants together in such a way that they will readily unite and continue to grow as one plant Budding is a variation of grafting in which the scion is a dormant bud with a small patch of attached bark Formation of roots on branches while they are still attached to the tree
- 43. 43 Grafting in oil seed tree species Grafting in oil seed tree species
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- 46. Factors affecting the choice between AR & NR Factors affecting the choice between AR & NR Risk of loss and determination of soil Crop composition Genetic consideration Risk of damage by pests Flexibility of operation Density of stocking Yield Time factor Cost 46
- 47. Artificial RegenerationArtificial Regeneration Controlled plant density Predictable seedling production High flexibility Low management intensity Option of introducing improved seed or plant material Changing species and/or varieties 47 AdvantagesAdvantages
- 48. Artificial RegenerationArtificial Regeneration Labors-intensive Temporarily disturbed root development Less adapted to micro-sites Cost-intensive 48 DisadvantagesDisadvantages
- 49. Quality planting stock More production Meet the industrial demand Assumed planting stock Resistant varieties Reduced rotation age Multiply suitable spp Clonal propagation Timing silvicultural operation 49 WHY WE GO TO NATURAL REGENERATION INTO ARTIFICIAL REGENERATION WHY WE GO TO NATURAL REGENERATION INTO ARTIFICIAL REGENERATION
- 51. 51 THANK U…!