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1、OBJECTIVES OF FOREST INSECT MANAGEMENT At the end of this section students should be able to:Have an understanding of the following ecological processes,concepts and pest management strategies.The dynamic events associated with forest succession and the role of forest insects in the process.The basi
2、c differences between forest insect management on federal forest lands versus on private lands.The mortality quotient and the concept of economic damage.The different insect pest management strategies including mechanical and physical control,chemical control,biological control,and some alternative
3、methods of insect control.The kinds of insecticides used in applied control and the different formulations of those chemicals.The basic differences between density dependent and density independent control.,Principles of Forest Insect Pest Management,Hickory Horned Devil,Regal Moth-adult of HickoryH
4、orned Devil,Philosophy of Forest Management1)Federal/State/County Lands2)Industrial and Private Forestry,Philosophy of Forest ManagementFederal/State/Government Lands:Focus on Ecosystem PreservationApproaches:Establish forest preservesLong rotationsEncourage recreation useProtect biodiversityProtect
5、 endangered species,Philosophy of Forest ManagementIndustrial and Private Lands:Focus on Intensive ForestryApproaches:Genetic ImprovementShort rotationsThinning and pruningNew technology in wood utilization and harvesting,Long Range Forest Management GoalsFederal Forestry:Maintaining Forest HealthIn
6、dustrial and Private Forestry:Protecting Investments,Ecological Roles of Insects:Herbivores Defoliators Gypsy mothPredators Checker beetles MantidsPrey Southern Pine Beetles,AphidsDetritivores termites,borersVectors Elm beetles&DEDPollinators,What is a pest?Pest status depends on population levels e
7、conomic factors&objectives of stand.(It is not your younger sibling),Some Review Terms:Equilibrium Position-The average population level of an insect species(EP).Economic Threshold-The population level at which management action should be taken to prevent the pest from reaching the economic injury l
8、evel(ET).Economic Injury Level-The lowest number of insects that will cause economic damage(EIL).Economic Damage-The amount of pest-caused damage that justifies the cost of applying pest control measures(ED).,Some Insects are never economic pests-the Equilibrium position(EP)is below the economic thr
9、eshold(ET)or Economic Injury level(EIL)Example:Eastern Tent caterpillar,Some insects are occasional pests and must be controlled at ET or they will reach EIL.Example:Spruce budworm,Douglas-fir Tussock Moth,Some insects are regular and serious pests the Equilibrium position(EP)is above EIL all the ti
10、me unless steps are taken to keep them low.Example:Seed and cone moths in seed orchards,Economic considerations in PestManagement include:Value of crop2)Cost of control 3)Pest status-depends on point of view,Approaches to Pest Management:Mechanical ControlChemical ControlBiological ControlIntegrated
11、 Pest Management,1)Mechanical Control:Fly swatters,1)Mechanical Control:,Fly swatters,Salvage logging,Sanitation,Water treatment of cut logs,Kiln drying of lumber,2)Chemical Control:Effects on insects and humans,Characteristics of Pesticides:,Specificity range of action,Persistence how long does it
12、last?,Toxicity How dangerous?,Measures of Toxicity,LD 50 dose(mg/kg)lethal to50%of test population-Oral or Dermal,Pesticides are poisons!,“Everyday Toxins”,Acute oral LD 50s(mg/kg),*For a 170 lb.male,Mode of Action of Pesticides:,Stomach Poisons Bacillus thuringiensis,Contact Poisons-Malathion,Syste
13、mics-Temik,Fumigants Methyl bromide,Repellents N,N-diethyl-meta-toluamide,Attractants fire ant baits,Insecticide Chemical Groups:,Nicotine tobacco plantsPyrethrum-chrysanthemumsRotenone tropical Derris plants,Characteristics:Quick knock downShort residual timeExpensive,a)Botanicals,b)Organochlorines
14、-also called Chlorinated hydrocarbonsDDTMethoxychlorLindaneChlordaneAldrin,Dieldrin,Endrin,Characteristics:Generally have long residueToxicity varies greatly,c)Organophosphates-Malathion,ParathionAll are Cholinesterase Inhibitors,Characteristics:Generally very effective Toxicity varies greatly-(Oral
15、 LD 50 Malathion 1375,Parathion 2 mg/kg)Short residual,CholinesteraseInhibition,d)Carbamates:carbyaryl(Sevin)or carbofuran(furdan)*Cholinesterase Inhibitors,Characteristics:Generally quite effectiveGenerally less toxic than OPCarbofuran is exception-Oral LD 50 8 mg/kgResidual limited,but longer than
16、 OP,e)Synthetic Pyrethroids Ambush,Warrior T,Pounce,Characteristics:Much more effective than natural PryrethrumUsed at very low ratesRelatively safe-LD50 about 250 mg/kgResistance by insects has become a serious problem,Formulation and Application of Insecticides:SpraysDustsWettable Powders(WP)Emuls
17、ifiable concentrates(EC)Ultra low volume sprays(ULV),Pesticide SafetyKeep away from childrenRead the LabelLegal contract between the user,the producer and the State and Federal GovernmentsRemember these are poisons!,Insect Growth Regulators:Development Juvenile Hormone(JH)Methoprene.Synthetic ecdyso
18、ne interferes with normal developmentCuticle formation-Diflubenzuron disrupts cuticle formation,inhibits molting process,Behavioral chemicals=semiochemicalsPheromones=chemicals used forcommunication within speciesSex PheromonesAggregation pheromonesAnti-aggregation pheromones,Behavioral chemicals=se
19、miochemicalsSpecific insect pheromones collected,analyzed and synthesized.Synthetic pheromone impregnated into rubber septum.Wendell Roel of(Cornell University)did much of the pioneering work in this field.,Pheromone may be used in insect control and pest management:1.Detection and monitoring2.Trap
20、outs Protection3.Attracticides4.Confusants,1.Detection and monitoring:Turf beetle,2.Trap outs/Protection:German Bark beetles,3.Attracticides:pheromone plusinsecticide Insects are attracted to the material and killed.Many ants are killed in this manner;Amdro,etc.,4.Confusants:German Grape berry Moth,
21、Biological Control:a)Action of natural enemiesb)Predatorsc)Parasites(Parasitoids)d)Pathogens,Biological Control:Usually density dependent-the percentage of hosts killed increases with population densityIn contrast,natural control factors(like weather)are density independentKill the same percentage o
22、f the pests regardless of population density,Native and Introduced biological control agentsPredators Preying mantidsLady bird beetles(ladybugs)Lacewing larvae and adultsGround beetles,Lacewingadult,Preyingmantid,Lady bird beetle(ladybug),Larva eating aphids,Parasitoids Chalcid waspsCynipid waspsIch
23、neumonid waspsNumerous Diptera,Value of Parasitoids vs.PredatorsParasitoidsGenerally very host specificWell synchronized with host biologyPredatorsNot host specific,can switch prey when food is scarcePopulations do not die out when one prey is gone,PathogensBacteria Bacillus thuringiensis,Bt Control
24、s many insect pestsFungi Entomophthorales spp.Infects Gypsy Moth larvaViruses NPV Nuclear Polyhydrosis virus(Gypsy Moth&other larva).GV Granulosis Virus(Douglas-fir Tussock Moth)Protoza Nosema Fall Webworm,Approaches to Biological ControlImportation from other countriesConservation that protect habi
25、tats of any biocontrol agents that may be presentEnhancement:Artificial rearing of agent for release to increase or“enhance”existing biocontrol populations,Advantages of Biological ControlControl is self-perpetuatingControl is selective and density dependentDoes not create new problems-normally,Disa
26、dvantages of Biological ControlNot effective against Direct Pestswhere any damage is unacceptableSome level of damage occurs and must be acceptableMust be implemented over large areasMay take years to become effective,Other Approaches to Insect Control:Host Resistance-Preference/non-preference Antib
27、iosis Tolerance-,Other Approaches to Insect Control:Legislative Control:Laws made to prevent entry or spread of pests.Quarantine against pine shoot borer.,Integrated Forest Pest Management,“The combination of all suitabletechniques to reduce or manipulatepest populations so that they remain below ec
28、onomically important levels”,Questions to for Principals of Forest Insect Management:1)What are the basic differences in management philosophy between those in Federal forestry and the private forestry companies?2)Why is control of seed orchard pests so important?Why is the approach used in seed orc
29、hards said to be similar to pest management in agriculture?3)What are the basic approaches to pest management used in forestry?4)What are the basic characteristics of commonly used insecticides?5)What is the LD 50 of a pesticide?6)What is the basic mode of action of the organophosphate and carbamate
30、 insecticides?7)What are semiochemicals and how can they be used in forest pest management?8)What is the difference between density dependent and density independent pest control?9)What type of biological agent was used in the control program of the larch casebearer?Would you characterize this as a program of introduction,conservation or enhancement?10)Why is Bacillus thuringensis used so often in control of forest Lepidoptera?11)What are the basic types of viruses used in control of forest pests?12)Explain why biological control agents are not effective at eradicating a pest species.,
