Study Guide
In this topic you will be learning about the common pests in Southwest landscape gardens and
how to manage them using integrated pest management (IPM). In a sustainable garden, the
primary aim is to manage your garden and landscape to prevent pests from building up to levels
that cause significant damage to plants rather than eliminating them entirely. If pest levels
become high, IPM offers a combination of four different techniques to use that can be
effectively used to reduce pest levels. Chemical pesticides might need to be applied, but these
chemicals should be used as the last resort rather than the first resort. After reviewing the
readings and watching the YouTube videos, students should be able to answer the following
questions.
1. Be able to define the following terms: pests, weeds, plant pathogens, and IPM.
●Pests: Any living organism, large or small, that reduces or lowers a landscape garden's
ability to provide the benefits we desire.
●Weeds: A weed is any plant that is growing in an undesirable location.
●Plant Pathogens: bacteria, viruses, and fungi that infect and damage plant tissues.
●(Integrated pest management or IPM): is a process used to solve pest problems while
minimizing health and safety risks to people and the environment.
2. What are some of the more common weeds found in Southwest landscape gardens?
●Cheese weed (Malva neglecta): a prolific and rapidly growing winter biennial with a large
taproot and edible leaves
●Goat head or puncture vine (Tribulus terrestris): a prostrate, summer annual that grows
many viciously sharp fruits that are a nightmare for barefoot walkers and bicyclists.
●Common Bermuda grass, a warm season perennial that is grown as a summer lawn in
central Arizona, but can also overrun garden spaces during the summer because it
spreads by stolons and underground rhizomes that make mechanical eradication next
to impossible.
●Prostrate spurge (Euphorbia humistrata): a fast spreading highly invasive ground-
hugging summer annual that provides a sheltered habitat for ants.
●Yellow Nut grass or nutsedge (Cyperus esculentus): an aggressive perennial that grows
small tubers underground and is exceptionally difficult to eradicate.
●Pigweed (Amaranthus fimbriatus): an upright growing winter annual that grows a long
thick taproot.
●Purslane (portulaca oleracea): a summer annual with succulent edible leaves that taste
a bit like spinach.
●Silver nightshade (Solanum elaeagnifolium): a highly poisonous warm season perennial
with a unique light purple flower.
●Stink net or globe chamomile (Oncosiphon piluferum): a quaint delicate but highly
aggressive cool season annual. Though it grows copious numbers of petite yellow
flowers.
●Stink net is currently number one on the list of most noxious weeds in central Arizona
because of how it is rapidly degrading Sonoran desert native habitat.
3. Be able to recognize a list of the common symptoms and signs of plant disease such as
heart rot (wood rot), powdery mildew, Texas root rot, and verticillium wilt.
●Heart Rot
○The most common fungal related disease found within larger wood producing
landscape perennial shrubs and trees is called heart rot.
○Heart rot is the fungus induced decay of inner wood that can cause large tree
limbs to suddenly and catastrophically fail or even kill large older mature
landscape tree specimens.
●Texas Root Rot
○
4. Know which type of mouthpiece (chewing, sucking or rasping) the insect pests listed below
have. Be familiar with the types of damage the following insect pests cause to plants:
caterpillars, aphids, whiteflies, beetles, scales, thrips, and spider mites.
(In notes)
5. Be able to list non-chemical means of managing insect pests and weeds using IPM. Be
aware of some of the beneficial insects that can be useful in managing insect pests including
lady beetles, lacewings and assassin bugs. What are some of the adverse effects of the using of
pesticides?
1) The first method is mechanical or physical control.
○Mechanical or physical control methods kill, remove, or exclude a pest directly, or
makes the environment unsuitable for it.
○Examples:
■ traps for rodents,
■ surface mulches to control weeds,
■ garden hose to spray off pests,
■ erecting barriers or fences to prevent pests
2) The second method is cultural control.
○Horticultural practices that reduce pest establishment, reproduction, dispersal
and survival.
○For example
■ changing irrigation practices
■ pulling weeds before they reproduce
■ Position garden plants within the garden space to resist or out compete
garden weeds for sunlight and soil nutrients
○Cultural control measures also include the use of landscape garden design
strategies to position garden plants within the garden space to resist or out
compete garden weeds for sunlight and soil nutrient
○For vegetable gardens, cultural control methods also include
■ rotating crop cycles by not planting the same vegetable plant species in
the same garden location
■ Don’t import soil disease pathogens into the garden site
● Here's a sustainable tip!!!
● When purchasing plants from a local garden center or plant nursery be
sure to inspect the root systems of the plants you want to buy.
● Healthy and disease-free root systems in nursery pots will appear white
firm and succulent and not brown blackened or mushy.
3) The third method is biological control.
○ the use of natural enemies, predators, parasites, pathogens, and competitors to
control pests and their damage.
○Invertebrates plant pathogens, nematodes, weeds, and vertebrates have many
natural enemies.
○For example
■ BT or Bacillus thuringiensis- an organic solution (a bacteria that is
sprayed onto the surface of garden leaves that will actively kill insects
with chewing mouthparts when it is ingested by these insects)
○Biological control can also involve the planting of disease resistant garden plant
species.
● Here's a sustainable tip!!!
○Killing all insects in your garden should not be your goal.
○Healthy ecosystems require an abundance of beneficial insects,
microbes, and fungi living in the soil, and on the plants.
○ Two effective IPM approaches are to introduce predatory insects,
such as ladybugs and praying mantids, and to create a healthy
garden habitat by building soil fertility.
6. For the IPM techniques list below, indicate whether it is an example of mechanical/physical,
cultural, biological, or chemical methods of pest management.
a. using lady beetles to manage aphids- biological control
b. hoeing weeds before the flower and fruit- cultural control
c. applying an pre-emergent herbicide to decomposed granite to manage weeds-
d. planting resistant tomatoes to prevent Verticillium wilt- biological control
e. using a garden hose with a high pressure nozzle to spray off insects that are
damaging plants- mechanic or physical control
f. use of Bt to manage caterpillars-
g. inspecting plant roots at garden nurseries
h. spraying insecticides to manage insects
j. using landscape mulches to control weeds
k. rotating the location of plants in your garden from season to season
7. When should you read a pesticide label? Know what are the signal words on a pesticide label
mean with respect to toxicity. Which word indicates the least toxic pesticide? the most toxic
pesticide?
8. After reading the posted article, be able to answer the following questions about pesticide
safety:
a. When is a pesticide applicator most vulnerable to pesticide poisoning?
b. What type of clothes should you wear when applying a pesticide?
c. What does wind speed have to do with safe pesticide application?
d. How should pesticides be stored? How should pesticides be disposed?
Video: Southwest Garden Pests
Introduction
● Southwest home gardens are designed, developed and maintained to provide a
plethora of benefits for people.
● In the babeleeze of ecology, we call these ecosystem services. Now these benefits
range from
○ growing our own food to eat
○ to provide a special place to enjoy an early morning cup of coffee and
○ To provide beauty of the southwest desert
● But! Southwest home gardens are also home to a plethora of other organisms, whether
intended by us or not.
○ These organisms share our garden spaces with us throughout the year forming
unique and dynamic tapestries of interactions that are shaped and affected by
the types of garden habitats that we create and maintain.
● In this video I'll discuss the kinds of pests that occur in our landscape gardens when the
unique tapestries of organisms in our landscape garden become unbalanced and
adversely impact the benefits that we intend our southwest home gardens to provide.
● In the second video, I'll review what are some of the sustainable garden practices that
can be done to restore the ecological balance of our special garden worlds.
What is a pest?
● Definition: Any living organism, large or small, that reduces or lowers a landscape
garden's ability to provide the benefits we desire.
○ In other words, a pest is any organism that in some way adversely or negatively
affects the health, habitat, productivity, or the aesthetic of the garden plants that
we are trying to grow.
What is by far the most common pest problem? Weeds!!
● What are weeds?
○ Definition : A weed is any plant that is growing in an undesirable location.
● Weeds compete
○ Compete for water, sunlight and soil nutrients.
○ Weeds also provide a habitat for other garden pest
○ Weeds can negatively affect or degrade the aesthetic or visual quality of a
landscape garden space.
●Many different species of common weeds
○ Cheese weed (Malva neglecta): a prolific and rapidly growing winter biennial with
a large taproot and edible leaves
○ Goat head or puncture vine (Tribulus terrestris): a prostrate, summer annual that
grows many viciously sharp fruits that are a nightmare for barefoot walkers and
bicyclists.
○ Common Bermuda grass, a warm season perennial that is grown as a summer
lawn in central Arizona, but can also overrun garden spaces during the summer
because it spreads by stolons and underground rhizomes that make mechanical
eradication next to impossible.
○ Prostrate spurge (Euphorbia humistrata): a fast spreading highly invasive
ground-hugging summer annual that provides a sheltered habitat for ants.
○ Yellow Nut grass or nutsedge (Cyperus esculentus): an aggressive perennial
that grows small tubers underground and is exceptionally difficult to eradicate.
○ Pigweed (Amaranthus fimbriatus): an upright growing winter annual that grows a
long thick taproot.
○ Purslane (portulaca oleracea): a summer annual with succulent edible leaves
that taste a bit like spinach.
○ Silver nightshade (Solanum elaeagnifolium): a highly poisonous warm season
perennial with a unique light purple flower.
○ Stink net or globe chamomile (Oncosiphon piluferum): a quaint delicate but highly
aggressive cool season annual. Though it grows copious numbers of petite
yellow flowers.
■ Stink net is currently number one on the list of most noxious weeds
in central Arizona because of how it is rapidly degrading Sonoran
desert native habitat.
Plan pathogens
●The second most common group by occurrence of Arizona landscape garden pests
●Plant pathogens: bacteria, viruses, and fungi that infect and damage plant tissues.
● Soil dwelling fungi are the most common plant pathogen in desert southwest
landscape gardens.
●Some common soil fungal diseases include
○ Plyophthora, Texas root rot, pythium, and verticillium wilt.
● These soil dwelling fungi can damage root and shoot plant tissues, sometimes even
causing plant death.
● Heart Rot
○ The most common fungal related disease found within larger wood producing
landscape perennial shrubs and trees is called heart rot.
■ Heart rot is the fungus induced decay of inner wood that can cause large
tree limbs to suddenly and catastrophically fail or even kill large older
mature landscape tree specimens.
● Other less common plant pathogens
○ Bacterial leaf spots
○ virus stem and root lesions
○ Airborne fungi that infect leaf tissues such as powdery mildew
○ Sudden vascular wilts caused by both bacteria and viruses living in the plant
conducting xylem and phloem tissues,
○ Virus induced growth abnormalities such as growth stunting, leaf yellowing or
galls.
Insects and arthropods
● Third group of pests
● Insects and arthropod species are always in our landscape gardens, but most often
they're unnoticed.
○ They only become pests when their populations grow outside the normal
ecological balance of nature and cause damage to our landscape garden plants.
● As pests, we group insects and arthropods according to their unique biological structures
and the types of damage they do to our landscape garden plants.
● We can divide them into three groups depending upon what kind of mouth parts they
have because the mouth parts that they have will dictate what type of damage they
cause to plants.
● Three types of insect mouth parts
○ Chewing
■ Caterpillar
● They normally can chew holes into leaves.
● They can actually chew up an entire leaf.
○ In fact, sometimes they'll chew up just the leaf blade and
leave the leaf veins intact. If that's the case then they're
called leaf skeletonizers.
● In addition to leaves, caterpillars can also cause damage to
stems, flowers and even roots.
● The damage they can cause can sometimes have a serious
impact on plant health and survival.
■ Beatles
■ Fly larva
● Mediterranean fruit fly: Chewing damage to fruits by this fruit fly is
actually caused by the immature fly larva
○ Sucking
■ Aphids
● the most common example of this kind of insect pest. Aphids, like
all sucking insects,
● take their mouthpieces and actually insert them into the phloem
conducting tissue of the plant sucking out the sugars in the
phloem.
● They can cause a problem on plants such as roses when their
population levels get exceptionally high
● They also can cause stunting of plants.
● The sugary excrement of aphids is called honeydew and can form
a thick and sticky layer on host plant leaves and stems.
● Aphid honeydew (crap) is often harvested by ants as a food
source!! In fact, ants are known to farm aphid populations on
plants for their honeydew,
● presence of ants in and around your garden plants is often
associated with the presence of aphids
■ Insects with sucking mouthparts can also transmit some plant diseases.
■ Other kinds of insect pests with sucking mouthparts include scale and
white flies
○ Rasping
■ They eat only the tops of leaves.
■ Ex: Thrips.
● Thrips feeds on very young developing leaves, especially citrus
leaves.
● Damage from thrips presents as malformed curled or cupped
leaves.
■ Ex: spider mites.
● Spider mites are not insects, but are rather arthropods or spiders,
● Damage to plants caused by spider mites can be a very serious
garden plant problem during the summer months, and presents
first as the browning or bronzing of leaves.
● Serious infestations of spider mites will also have a thick matrix of
webbing surrounding the plant leaves.
● Spider mites occur most frequently on evergreen landscape
plants like juniper or roses or on summer vegetable garden plants
such as peppers, squash, or eggplant.
Larger animals
● The fourth and last group of pests
● are those that usually live outside our landscape garden spaces but sometimes frequent
our gardens when hungry or thirsty.
● These pests include small rodents, birds, rabbits, javelina, and even coyotes.
○ These larger animals might not frequently visit your garden space but when they
do the amount of damage that they can do to your landscape garden plants in a
short period of time can be significant!!!
● Oftentimes, their presence in one's garden is directly related to the proximity that the
garden is from open desert habitat, and whether or not there is sufficient native food or
forage available.
● For example, during times of extended dryness these desert animals will move into
urban areas in search of food and water.
Outro
● Correctly identifying the pests in your landscape garden is key to knowing whether a
pest is likely to become a problem or not, and if so determining what is the best
management strategy.
● In this video, we've identified what are the four most common kinds of pests found in our
southwest home landscapes and gardens.
● They are in order of problem and occurrence; weeds, microorganisms such as bacteria
viruses and fungi that we call disease pathogens, small animals such as insects and
arthropods, and finally larger animals such as birds, rabbits, javelina, or even coyotes.
● In our second video on southwest home garden pests, we'll discuss the use of
integrated pest management as a sustainable strategy for managing your garden pest
problems in ways that are both healthy and sustainable.
Video: Integrated Pest Management
Intro
● I'll review what are some of the garden management practices that can be done to
restore the ecological balance of our special garden worlds.
● Focus on the concept of integrated pest management or IPM, as a tool for managing
pest problems in our landscape gardens in ways that promote personal and public health
and garden sustainability.
Managing pest outbreaks
● Managing pest outbreaks in a sustainable manner involves a strategy called integrated
pest management.
●Definition (Integrated pest management or IPM): is a process used to solve pest
problems while minimizing health and safety risks to people and the environment.
● IPM is an ecosystem-based approach to pest management
●Focus: long-term prevention of pests and their potential damage to our landscape
garden plants through the use of a combination of techniques
● Examples of IPM techniques
○observation and monitoring
○habitat manipulation
○modification of cultural practices
○biological control
○use of pest resistant plant varieties.
● Use of chemical pesticides in landscape gardens in NOT a priority
● Instead preemptive or preventive control measures and actions are preferred to
keep pests from becoming a problem,
○Examples: growing a healthy crop that can withstand pest attacks, using disease-
resistant plants, or erecting barriers such as fencing to keep animals from
accessing our garden spaces.
● IPM means first analyzing environmental and garden site factors that affect pests and
their ability to access our garden environments and thrive.
● If pest problems do occur control techniques are selected that are least harmful to
people and the other garden organisms.
What is Integrated Pest Management
● The first (and most important) part of a successful IPM program in your home landscape
garden is called observation and monitoring.
● This means regularly checking your landscape garden area to monitor garden plant
health and development, and to identify if pests are present, and if so how many are
there, or what kind of damage are they causing.
●Correctly identifying the pest is the first key to knowing whether a pest is likely to
become a serious problem and determining the best management strategy to mitigate
damage to any landscape garden plants.
●After monitoring and researching information one can then decide whether a pest
problem, if present, can be merely tolerated and allowed to naturally go away over time,
or whether it is a problem that is severe enough that it warrants implementation of direct
control measures.
●If control measures are needed, then this information you've collected from your
observation and monitoring activities about the pest can help you select the most safe
and effective management methods, and the best time to use them.
Four IPM methods
1) The first method is mechanical or physical control.
○Mechanical or physical control methods kill, remove, or exclude a pest directly, or
makes the environment unsuitable for it.
○Examples:
■ traps for rodents,
■ surface mulches to control weeds,
■ garden hose to spray off pests,
■ erecting barriers or fences to prevent pests
2) The second method is cultural control.
○Horticultural practices that reduce pest establishment, reproduction, dispersal
and survival.
○For example
■ changing irrigation practices
■ pulling weeds before they reproduce
■ Position garden plants within the garden space to resist or out compete
garden weeds for sunlight and soil nutrients
○Cultural control measures also include the use of landscape garden design
strategies to position garden plants within the garden space to resist or out
compete garden weeds for sunlight and soil nutrient
○For vegetable gardens, cultural control methods also include
■ rotating crop cycles by not planting the same vegetable plant species in
the same garden location
■ Don’t import soil disease pathogens into the garden site
● Here's a sustainable tip!!!
● When purchasing plants from a local garden center or plant nursery be
sure to inspect the root systems of the plants you want to buy.
● Healthy and disease-free root systems in nursery pots will appear white
firm and succulent and not brown blackened or mushy.
3) The third method is biological control.
○ the use of natural enemies, predators, parasites, pathogens, and competitors to
control pests and their damage.
○Invertebrates plant pathogens, nematodes, weeds, and vertebrates have many
natural enemies.
○For example
■ BT or Bacillus thuringiensis- an organic solution (a bacteria that is
sprayed onto the surface of garden leaves that will actively kill insects
with chewing mouthparts when it is ingested by these insects)
○Biological control can also involve the planting of disease resistant garden plant
species.
● Here's a sustainable tip!!!
○Killing all insects in your garden should not be your goal.
○Healthy ecosystems require an abundance of beneficial insects,
microbes, and fungi living in the soil, and on the plants.
○ Two effective IPM approaches are to introduce predatory insects,
such as ladybugs and praying mantids, and to create a healthy
garden habitat by building soil fertility.
4) Chemical control methods
● Chemical pesticides are a method of last resort.
● Use chemical control to remove only the target pest organisms
● Chemical herbicides are not recommended use around food production areas
● Both synthetic and natural chemical pesticides are best used according to established
guidelines for their use, and also in combination with the other three IPM methods.
● Chemical pesticides are selected and applied only in ways that minimize their possible
harm to people, non-target organisms, and the environment.
● Additionally, chemical pesticides should be used with the goal of only removing the
target pest organism.
● The most common and oftentimes only chemical pesticide used in horticulture today
are herbicides to control weed pests in ornamental landscaped spaces that are too large
for the practical use of other control methods.
● Only use the most selective chemical pesticides that will do the job and be the safest for
people, other organisms, and for air soil and water quality.
● For example:
○use pesticides in bait stations to control insects or small rodents,
○or spot spray a few weed species instead of applying herbicides indiscriminately
to an entire area,
● Remember to always follow the product labeled instructions for the proper use, storage
and disposal of any chemical pesticide.
Here's a sustainable tip!!!
● Some organic or natural pesticide options to control pests include oils and soaps, Neem
oil, diatomaceous earth, and garlic and chili pepper extracts. But just because these are
organic natural or homemade concoctions doesn't mean that they can never cause harm
to your soil your garden or people..
● Be sure to do your homework and choose the most effective and safest organic or
natural pesticide for you and your garden.
Most effective long-term way to manage pests
● The most effective long-term way to manage pests starts with observation and
monitoring, and then uses a combination of IPM methods that we've been discussing in
this video.
● Always remember that the full elimination of all garden pests is really an unrealistic
expectation.
● Rather, IPM focuses on pest prevention and strengthening a garden's natural pest
resistance.
● Natural pest resistance within any landscape garden is best realized by designing,
installing, and maintaining a landscape garden site that has a healthy, diverse and
robust ecological balance of beneficial organisms.
● Practicing integrated pest management as a strategy for managing your landscape
garden will improve your garden's ecological balance and biological sustainability.
