Sci (Ecology) Flashcards
1
Q
What is Ecology?
A
- Study of the relationship between biotic factors with other living organisms and their nonliving environment (abiotic factors
- Biotic factors: animals, plants, bacteria, fungi, protists
- Abiotic factors: water, O2, rocks, sand, soil, light, temperature, wind, pH
2
Q
How the body is organized?
A
- Smallest units of living things are molecules (chemical elements bonded together into compounds), ex. Oxygen, carbon dioxide, glucose, proteins.
- Molecules are organized into functioning, living units called cells, nerve cells, etc.
- The cells are grouped together by their specialized functions into tissues, e.g., epidermal tissues, nervous tissues, etc.
- Tissues are assembled into organs, each with a special function to perform, e.g., heart, liver, kidney.
- Organs are organized into systems. Each system has major functions, e.g., respiration, circulation, digestion
- The systems of the body are coordinated and integrated into the total living body. Each is important but dependent upon the others.
3
Q
Organization of living matter
A
- Matter is organized by organisms to populations to communities to ecosystems all under one biosphere.
4
Q
Ecology Overview
A
- From the levels of biological organization, ecology begins with the entire organism and extends to the biosphere. Ecology is the study of the relationships between living organisms (biotic factors) with each other and between living organisms and their non-living (abiotic factors) environment.
5
Q
Earth’s Spheres:
A
- Earth’s atmosphere: the earth’s gravity holds gases near its surface. It extends 100km up, it is critical to life on earth, and is composed of 78% N2, 21% O2, <1% Ar + H2O vapour, CO2. It also acts like a blanket and moderates surface temperatures.
- Atmosphere: the layer of gases surrounding Earth.
- Lithosphere: Rocky solid outer shell of Earth (50-150 km thick).
- Hydrosphere: Regions of water on/above/below the Earth’s surface. All of Earth’s water in solid-liquid-and-gas form.
- Biosphere: Region on the planet which can support life. Layer of ground, water, and lower atmosphere.
6
Q
Gaia Hypothesis:
A
James Lovelock proposed that Earth, through interactions among the 4 spheres, behaved like a living organism. He suggested that Earth was capable of responding to changes in the environment (such as incoming sunlight) and maintaining relatively consistent internal conditions over long periods of time - just like a living cell.
7
Q
Earth’s mass is related to…
A
its ability to have an atmosphere as it creates a force strong enough to hold gases near its surface.
8
Q
The atmosphere enhances conditions of life on Earth because it acts like a…
A
blanket and moderates surface temperatures. The insulation prevents excessive heating during the day and cooling at night. Without an atmosphere, the surface temperature would drop from 15 degrees to -18 degrees. It also blocks solar radiation such as ultraviolet light (linked to skin cancer). Without an atmosphere, most species would die.
9
Q
Biosphere describes the locations in which…
A
life can exist within the 4 spheres. Most of the easily observed life forms exist on land and in water, but micro-organisms exist several km beneath the surface. The biosphere is found within each of these spheres.
10
Q
Though the Earth is large, scientists consider the biosphere to be…
A
as fragile as it is thin compared to Earth. All conditions required for life must be met and maintained within this thin layer of ground, water, and lower atmosphere.
11
Q
Ecology:
A
It is the study of the relationships/interactions between biotic organisms with each other and their abiotic environment (ex. Everything that affects organism during lifetime)
12
Q
Biotic:
A
The living factors that affect an ecosystem; living things, their remains, and features, such as nests, associated with their activities ex. all living organisms in a pond
13
Q
Abiotic:
A
The non-living factors that affect an ecosystem ex. physical factors (temperature, light, precipitation, wind, etc.) & chemical factors (pH, oxygen levels, soil content (Fe, Mg, nitrates)) The non-living physical and chemical components of an ecosystem.
14
Q
Habitat:
A
The place where an organism lives eg. organisms: snail, earthworm; habitats: marsh, soil
15
Q
Niche:
A
The total role of an organism in an ecosystem ex. the niche of a deer is to: feed on grass and other plants, become food for wolves, provide blood for mosquitoes + etc, fertilize soil with its waste, reproduce
16
Q
Trophic Levels:
A
feeding levels (position in a food chain within their ecosystem) used to classify organisms in an ecosystem. The level of an organism in an ecosystem depending on its feeding position along a food chain.
1) Producer
2) Consumers
3) Decomposer
17
Q
Producer:
A
Also known as autotrophs (self-feeder) - organism that can make its own food through photosynthesis;
18
Q
Consumers:
A
Also known as the heterotrophs (other feeder) - organism that cannot produce ITS OWN food, and must consume other organisms.
19
Q
Herbivores:
A
Consumer that eats only plants - deer, rabbits, elks, cow, buffalo
20
Q
Carnivores:
A
Consumer that eats only animals - hawks, lion, wolf, alligator, hyena
21
Q
Omnivores:
A
Consumer that eats both plants and animals - foxes, racoons, humans, pig
22
Q
Predator:
A
A carnivore which feeds on live animals
23
Q
Prey:
A
The live animal which is killed and eaten by a predator
24
Q
Parasite:
A
Organism that uses another organism as a home and source of food
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Host:
Organism that the parasite lives on
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Decomposer:
An organism that breaks down and feeds on nonliving organic matter (dead plants, animal, and animal wastes). Returning valuable nutrients to the environment, so that they can be re-used by producers ex. bacteria, fungi (moulds, yeast, etc.)
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Levels of organization:
- Organism
- Population
- Community
- Ecosystem
- Ecotone
- Biome
- Biosphere
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Organism:
An individual living thing
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Population:
A group of organisms of the same species
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Community:
A group of various populations living together
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Ecosystem:
An area in which biotic factors are interacting with abiotic factors; all the living organisms and their physical and chemical environment
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Ecotone:
A transition area between two ecosystems that includes members of the community of both ecosystems;
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Biome:
A large area (ex. B.C.) with a characteristic climate and geography (eg. desert, tropical rainforest)
34
Biosphere:
The entire region on earth in which life is able to exist
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Species Interactions:
- No living organisms are in isolation. We study their ‘feeding relationships’ by examining food chains and food webs within the ecosystem.
- Food chain - shows a simple LINEAR feeding relationship. MAX: 6
- → = is eaten by
- Grass (producer) → rabbit (primary consumer/1o) → coyote - terrestrial food chain
- All food chains start with a producer.
- Other feeding relationships create food webs;A better way to represent ALL the feeding relationships within an ecosystem is to use a Food Web
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Aquatic Ecosystems:
An aquatic ecosystem is an ecosystem that is based in or on water ex. Pond, puddle, ocean.
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Terrestrial Ecosystems:
An ecosystem based on land
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Flow of Energy Through an Ecosystem:
- The sun is the ultimate source of energy. 0.023% of light energy converted by producers to (ATP*) food (C.P.E.).
- ATP Energy = Adenosine Triphosphate (C.P.E.).
- Only 10% of energy is passed to the next trophic level. 90% of energy used by organisms for life functions.
- Elements of LIFE: C, H, N, O, P, S.; Energy in living humans is chemical bonds holding the molecules together.
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Ecological Pyramids:
- Pyramid of Numbers
- Pyramid of Biomass
- Pyramid of Energy
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Pyramid of Numbers:
- NOTE: the number of organisms at each trophic level indicates how many are needed to sustain life at the level above.
- Disadvantages: this system ignores the fact that equal numbers of different organisms have different masses ex. 11 mosquitoes doesn’t equal 11 birds
41
Pyramid of Biomass:
- NOTE: the mass at each level indicates the mass that can be sustained at the level above.
- Disadvantages: ignores the fact that equal masses of different organisms have a different energy content. Ex. 1 kg of butter doesn’t equal 1 kg of lettuce.
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Pyramid of Energy:
- Food is ultimately valued by its energy content
- Units of food energy - kilojoules (KJ), kilocalories (Kcal), Calories (cal)
- This pyramid shows the flow of food energy in a food chain
- The shape of the pyramid illustrates the loss of energy into the environment as one moves through the food chain.
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Cycling Matter:
- Biogeochemical cycle
- Water cycle
- Carbon cycle
- Nitrogen cycle
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Biogeochemical cycle:
The movement of matter through the biotic and abiotic environment
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Water cycle:
The series of processes that cycle water through the environment
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Carbon cycle:
The biogeochemical cycle in which carbon is cycled through the lithosphere, atmosphere, hydrosphere, and biosphere
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Nitrogen cycle:
The series of processes in which nitrogen compounds are moved through the biotic and abiotic environment
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Biotic/Abiotic Influences on Ecosystems:
- Limiting factor
- Tolerance range
- Carrying Capacity
- Both biotic and abiotic factors influence where a species can live.
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Limiting factor:
Any factor that restricts the size of a population
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Tolerance range:
The abiotic conditions within which a species can survive
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Carrying Capacity:
The maximum population size of a particular species that a given ecosystem can sustain
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Influences of Abiotic Factors:
- Temperature, soil (pH & composition), light availability, precipitation, water salinity.
- Species will experience stress near the upper and lower limits of the tolerance range. Stress will reduce their health, rate of growth, reproduction.
- Species are MOST successful at the optimal range - this is where the species is best adapted to their environment.
- Largest healthiest populations occur within the optimal range.
- Some species have wide tolerance ranges - others have narrow ranges of tolerance.
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Humans effects on key abiotic factors
1. Ecosystem: Terrestrial
- Abiotic factor + human action and result:
- Light availability: Clear-cutting and fire remove shade and expose the remaining organisms to much more light.
- Water availability: Damming rivers and draining swamps and marshes change water availability. Irrigation increases water availability.
- Nutrient Availability: Farming practices may increase or decrease nutrient levels in the soil.
- Temperature: Global warming is decreasing suitable habitat for many cool-adapted species.
54
Humans effects on key abiotic factors
2. Ecosystem: Aquatic
- Abiotic factor + human action and result:
- Light availability: Activities that increase erosion or stir up the bottom cloud the water and reduce light penetration.
- Nutrient availability: Nutrient runoff from agriculture and urban environments increases the nutrient content of surface water and groundwater, causing algal blooms.
- Acidity: Acidic air pollution results in acid precipitation. Carbon dioxide emissions produced by the burning of fossil fuels are increasing the acidity of the oceans.
- Temperature: Industries and power plants release heated waste water into lakes and rivers, killing fish and other organisms.
- Salinity: Salting highways and long-term irrigation practices can cause salt to accumulate.
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Species Interactions:
- Competition (-/-)
- Predation (+/-)
- Mutualism (+/+)
- Parasitism (-/+)
- Commensalism (+/o)
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Competition (-/-)
Two individuals vie for the same resource. Ex. Foxes and coyotes both feed on common prey such as mice and rabbits. Humans and insects compete for the same crop plants.
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Predation (+/-)
One individual feeds on another. Ex. Lynx prey on snowshoe hares. Leeches and black flies are ‘micro-predators’ that feed on humans.
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Mutualism (+/+)
Two individuals benefiting each other. Ex. Nitrogen-fixing bacteria live in the roots of certain plants. The plants provide sugars to the bacteria. The bacteria provide nitrogen to the plant.
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Parasitism (-/+)
One individual lives on or in and feeds on a host organism. Ex. Tapeworms are parasites of cats and dogs. Microbes that cause malaria live within human blood cells.
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Commensalism (+/o)
One individual benefits and the other neither benefits nor is harmed. Ex. Many birds nest in particular kinds of trees or in abandoned burrows. Spanish moss lives on certain tree species.
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Carrying Capacity:
- The upper sustainable limit that the ecosystem can support. It can be altered through natural or human activity when resources are removed or added to the ecosystem.
- The loss or induction of a species can change the carrying capacity for other species.
62
Owl Pellet lab:
- An owl does not have teeth therefore they cannot chew food. When eating, they slowly digest the meal by separating the soft materials such as meat from the hard materials such as bones.
- It then regurgitates the harder materials and indigestible items such as feathers as an owl pellet.
63
Energy in Ecosystems:
Photosynthesis
- Photosynthesis: is the process (a series of chemical reactions) by which green plants and certain other organisms transform light energy into C.P.E. Energy is stored. Producers convert the energy from the sun into chemical energy, stored in the chemical bonds of glucose molecules. (Sugar - C6H12O6).
- Photosynthesis occurs in the chloroplast inside the plant cells. It is a chemical reaction which needs chlorophyll (catalyst), the green pigment inside chloroplasts.
- Photosynthesis is: Carbon dioxide + water + light energy → glucose + oxygen or
- 6CO2 + 6H2O → C6H12O6 + 6O2 (Summative equation - end result).
- Raw materials: CO2, H2O, light energy; Products: Sugar (glucose), oxygen
64
Energy in Ecosystems:
Cellular Respiration
- Cellular Respiration - the process (series of chemical reactions) by which organisms convert the CPE in food molecules into a usable form (ATP) of energy that can be used for ALL life - sustaining activities.
- Energy is released - glucose sugar is burned (it reacts with oxygen) to release the energy which was stored in its bonds. Carbon dioxide and water are produced.
- Occurs in mitochondria (powerhouse of cell) in animal cells (plant + animal). The energy released is used to drive ALL cellular metabolic processes ex protein synthesis, DNA replication, mitosis. C.R. - Glucose + Oxygen → Carbon Dioxide + Water + E
- C6H12O6 +6O2 → 6CO2 + 6H2O *Energy in ecosystems is not recycled.
- Raw materials: glucose, oxygen; products: water, carbon dioxide.
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Photosynthesis
More info
- Cell that carries out process
Chloroplast
- Organelle that carries process
Chloroplast
- Reactants
CO2, H2O
- Products
O2, glucose
- Energy required?
Yes
- Energy released?
Yes
- Type of Energy
Light Energy
- Importance to organism that performs the process?
Responsible for the oxygen that makes humans live
- Importance to other organisms?
Essential to all life on Earth
66
Cellular Respiration
More info
- Cell that carries out process
Mitochondria
- Organelle that carries process
Mitochondria
- Reactants
Glucose, O2
- Products
H20, CO2
- Energy required?
Yes
- Energy released?
Yes
- Type of Energy
Metabolic Pathway
- Importance to organism that performs the process?
Provides cells with the energy needed to function
- Importance to other organisms?
Provides energy for cells to live
67
Biomes:
A large geographical region defined by climate (precipitation and temperature) with a specific set of biotic and abiotic features
68
Biomes:
More info
• Precipitation and temperature are the main abiotic factors influencing biome formation.
• Terrestrial biomes have distinct biotic and abiotic characteristics.
• The five main Canadian biomes are tundra, boreal forest, grassland, temperate deciduous forest, and mountain forest.
• The boreal forest is the largest biome in Canada.
69
The 5 Major Canadian Terrestrial Biomes
- Tundra
- Boreal Forest
- Temperate Deciduous Forest
- Grassland
- Mountain Forest
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Tundra
Abiotic factors
Low temps. for most of the year, short growing season, permafrost layer beneath soil, precipitation from 0-25 cm/yr, poor soil quality.
71
Tundra
Biotic factors
Low diversity, rapid-flowering plants, mosses and lichens, caribou, ptarmigan, lemmings, arctic foxes.
72
Boreal Forest
Abiotic factors
Warmer than tundra, no permafrost, changeable weather, soil contains some water and is acidic, precipitation - 40cm or more/yr.
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Boreal Forest
Biotic factors
Coniferous trees, seed-eating birds, squirrels, voles, snowshoe hares, black bears, pine martens, gray wolves.
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Temperate Deciduous Forest
Abiotic factors
Longer growing season than boreal forest, higher temperatures than tundra or boreal forest, fertile soil, precipitation up to 100 cm/yr.
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Temperate Deciduous Forest
Biotic factors
Deciduous trees and other flowering plants, tree and ground squirrels, many insects, shrews and mice, deer, black bears, hummingbirds, and weasels.
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Grassland
Abiotic factors
Longer growing season than boreal forest, higher temperatures than tundra or boreal forest, rich and fertile soil, precipitation from 25-75 cm/yr.
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Grassland
Biotic factors
Fescue grasses, grasshoppers, bison, voles and mice, snakes, hawks, and coyotes.
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Mountain Forest
Abiotic factors
Temperatures vary with elevation, cool summers, windy conditions, heavy precipitation on the leeward side of mountains, and fast-flowing rivers.
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Mountain Forest
Biotic factors
Marmots, squirrels, elk, black and grizzly bear, cougar, large coniferous tree, ferns.
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Biodiversity:
It refers to the variety of living species found in an ecosystem. It is often measured by counting the number of species in that ecosystem - this is known as ‘species richness’.
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Biodiversity:
More info
More energy + available nutrients means greater biodiversity and population numbers. Ex. tropical rain forest has the highest biodiversity, tundra has the lowest biodiversity.
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Species richness:
The number of species in an area
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Extinct:
- Refers to a species that has died out and no longer exists anywhere on Earth
- ex. Great auk, sea mink, passenger pigeon
84
Extirpated:
- A species that no longer exists in a specific area
- ex. Paddlefish (all of Canada), Atlantic walrus (N.W. Atlantic)
85
Endangered:
- A species facing imminent extirpation or extinction
- ex. Barn owl (some regions), swift fox, northern cricket frog
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Threatened:
- A species that is likely to become endangered if factors reducing its survival are not changed
- ex. Humpback whale, wood bison, kentucky coffee tree
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Special Concern:
- A species that may become threatened or endangered because of a combination of factors.
- ex. Polar bear, red-headed woodpecker, atlantic cod
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Sustainability:
Refers to an ecosystems ability to support life and maintain an ecological balance = maintain resources for future generations.
- The greater the biodiversity:
- The greater the opportunity to find food
- The more stable the ecosystem (if a species disappears there will be less severe consequences);-
- The greater the opportunity to find new forms of food
- All species keep the biosphere healthy = providing food, cleaning air and water, making soil
89
Extinction occurs as a result of HIPPO
What is HIPPO?
H - habitat destruction,
I - invasive species (take over food supply or habitat),
P - population growth of humans,
P - pollution,
O - overconsumption (a species is hunted/consumed to a point where the numbers are so few that they are unable to sustain a healthy population.
- In Canada there are approximately 564 species ‘at risk’
90
Non-Native Species
It is a species that is NOT indigenous to an ecosystem. If an ‘introduced’ (alien) species becomes successful in its new environment it can have a negative impact on the other native species in that ecosystem.
- If so it is referred to as an invasive species; over 3000 invasive species in Canada, 185 in Great Lakes ex. Carp, earwig
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Consequences of:
Ecological impact
- Invasive species compete with or feed on native species leading to population decline or extinction.
- Invasive species change ecosystem dynamics by altering nutrient cycles or energy flow.
92
Consequences of:
Economic impact
- Damage to forests & agricultural crops causes financial loss
- Competition with invasive plants lowers crop yields.
Diseases & pests may destroy livestock & crops, kill trees, and harm important species such as honeybees.
93
Consequences of:
Tourism impact
• Species loss and reduced water quality have negative impacts on wildlife viewing, fishing, and water-based recreation.
• Waterways can become choked with invasive aquatic plants, rendering them impassable to boats.
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Consequences of:
Health impact
• Disease-causing organisms, such as the West Nile virus, are introduced.
• Pesticides used to control invasive species cause pollution and are health risks.
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Methods of controlling introduced species:
1) Chemical - most widely used; pesticides & herbicides; reduce crop damage BUT environmental risk may kill non-target species.
2) Mechanical - removal or physical barriers; ex. Cootes paradise - trap carp in sorting chamber - put back out in the lake.
3) Biological -intentionally introduce organisms to control invasive species ex. Insects to eat purple loosestrife (tall purple flower) *** must be sure the control species won’t consume other native species.
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Pollution:
- The release of harmful contaminants (toxic materials) into the environment.
- Ex. pesticides, fertilizers, car exhaust, and plastics. Micro-plastics are found within food and are dangerous to the body.
97
Pollution:
More info
- For tens of thousands of years indigenous people have existed in sustainable ecosystems around the world. Living in harmony with nature.
- 2 factors have changed the relationship humans have with the environment.
1) Human population has drastically increased - more people = more waste (industrial, agricultural, medical, and revolutions.
2) Many synthetic chemicals (man-made) have been invented - these chemicals are toxic and persistent.
98
Neutralize:
Counteract the chemical properties of an acid.
99
Bioremediation:
The use of microorganisms to consume and break down environmental pollutants.
100
Acid Precipitation (Acid Rain):
- Precipitation that has been made more acidic than usual by the combination of certain chemicals in the air with water vapor.
- Acid rain can cause biodiversity such as species in lakes to disappear. It can also chemically change soil which would be depleted and affect the nutrients of plants.
- Minerals such as limestone are able to neutralize/counteract acid.
- Acid rain affects terrestrial ecosystems and humans by damaging vegetation and causing slower growth of crops. Sulfur dioxide is toxic to humans and aggravates respiratory problems such as asthma and bronchitis.
- To reduce acid rain, forests in affected areas must rely on poorer soils, and dispersing pollutants over greater distances - smaller effects
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Oil Spills:
- Oil spills are so devastating as oil is toxic, slow to break down, and difficult to clean up. It forms large slicks that cover the ocean, beach, and seabed.
- Four methods that can be used after an oil spill:
1) Skimming/vacuuming - into a recovery vessel for permeable sea conditions
2) Bioremediation - microorganisms can feed + weak down on oil
3) Burning - oil can be lit on fire so it can be burnt away
4) Dispersal agents - oil broken into small droplets using detergent
102
Plastics at Sea:
- < a billion kilograms (1 million tonnes) of plastic is produced worldwide each year.
- Only a tiny fraction of plastic is recycled and most ends up in landfills, waterways, and oceans.
- Plastic damages ecosystems as types of species may mistake tiny plastic for food and may die. Also some species may get stuck/tangled within plastic.
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Soil Nutrients:
As crops grow they take up nutrients from the soil and incorporate them into their tissue. The most important nutrients are nitrogen, phosphorus, and potassium.
104
Agroecosystems:
An agricultural ecosystem modified by humans
105
Synthetic fertilizer:
& examples
Fertilizers that are manufactured using chemical processes
Ex. Ammonia, synthetic urea, potash, potassium, commercial chemical fertilizers
106
Natural fertilizer:
& examples
Plant nutrients that have been obtained from natural sources and have not been chemically altered
by humans.
Ex. Animal manure, sludge, plant materials such as seaweed and compost, blood meal, bone meal, wood ashes
107
Synthetic fertilizer:
Advantages
• nutrients are released quickly
• amounts of nutrients can be precisely measured
• relatively easy to apply
108
Synthetic fertilizer:
Disadvantages
• production is energy intensive
• cause water pollution
• nutrients lost from soil through leaching
• can cause an imbalance in
soil chemistry and upset the balance of soil microorganisms
109
Natural fertilizer:
Advantages
• less danger of over fertilizing
• release nutrients slowly
• can improve soil structure
• benefit soil microorganisms and nutrient cycling
110
Natural fertilizer:
Disadvantages
• low concentrations of nutrients
• release of nutrients may be slower than desired
• not easy to measure the quantity of nutrients
• may be more difficult to apply
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Pesticide:
Substance (poison) that causes physical or biological harm with the intent to kill an unwanted organism. Herbicides - killing plants, Insecticides - killing insects, Rodenticides - killing rodents, Fungicides - killing fungus, Molluscicides - killing mollusca (snails, slugs), Piscicides - killing fish.
112
Pesticides:
More info
Agroecosystems have extremely low biodiversity - due to monoculture (single crop species planting) and use of pesticides. As a result, large scale food production has dramatic ecological impacts: habitat loss, alters food webs, affects biogeochemical cycles.
113
Pests:
Organisms that might compete with or damage crop species. Term used in reference to human wants - no such thing as a ‘pest’ in nature.
114
Agricultural Pests:
Plants and animals that reduce crop yields
115
Broad spectrum (kills lots) pesticides:
Toxic to a wide range of species - often kill non-target species. Ex. DDT - dichlorodiphenyltrichloroethane - toxic to most insect species.
116
Broad spectrum pesticides can result in:
- Greater dependency because they are killing potentially beneficial organisms - might be killing a species that is a natural predator of the pest.
- Bioaccumulation - concentration of pesticide increases to dangerous toxic levels - affects the food chain.
- Pesticide resistance
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Narrow spectrum pesticides:
Toxic to a limited number of species ex. Bacillus thuringiensis - toxic to caterpillars, beetle larvae and fly larvae - not toxic to beneficial insects.
118
DDT
- Synthetic
- Broad spectrum use
- Characteristics
• one of the first widely used synthetic pesticides
• highly persistent in food chains causing die-off of many predatory birds
• widely banned in 1970s but still used in some countries to kill mosquitoes that transmit malaria
119
Rotenone
- Natural toxin extracted from plant roots
- Insecticide and pesticide
- Characteristics
• highly toxic to many aquatic organisms, including fish
• approved for use by some organic farmers
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Glyphosate
- Synthetic
- Broad spectrum herbicide
- Characteristics
• widely used herbicide
• very low persistence
121
Bt
- A protein obtained from the bacteria Bacillus thuringiensis
- Narrow spectrum insecticide
- Characteristics
• highly toxic to moth and butterfly caterpillars
• safer than most pesticides
