Post on 14-May-2015
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Out of the Wilds and Into Your Garden
Gardening with Western L.A. County Native Plants Project SOUND - 2009
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Pests, Pests, Pests
C.M. Vadheim and T. Drake
CSUDH & Madrona Marsh Preserve
Madrona Marsh Preserve
March 7 & 10, 2009
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What is a pest? An organism which has characteristics that are regarded by humans as injurious or unwanted
Eats a desired plant Causes disease in a desired
plant Carries disease to a desired
plant
May be:
A vertebrate (deer; rabbit) An insect/mollusk (snail) A bacterium, virus or fungus
A pest in one setting may be beneficial in another; like a weed, a pest may be an organism ‘in the wrong place’
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Predator/prey relationships in nature
http://www.champaignschools.org/science/images/foodweb.gif
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In nature, plants fight back…
Native plants evolved with insects, other animals, microorganisms – ecosystems in balance
Some produce noxious chemicals or physical barriers to ‘ward off’ natural pests
Some attract ‘helper species’ – insects & even birds
Some simply tolerate normal levels of predation
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A recipe for disaster
http://jenmill.blogspot.com/2006_04_01_archive.html
http://farm2.static.flickr.com/1118/814174806_a1348ae709.jpg
Plant species not native to area; often ‘cultivars’
Planted in mono-culture
Heavily watered & fertilized – ‘plants on steroids’
Using overhead watering during warm summer days
Globalization of pests
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The ‘Old California Garden’ requires an
arsenal of ammunition…
Issues:
Improper use
Overuse
Storage
http://www.improvementscatalog.com/home/improvements
/792923315-spray-doc-wheel-garden-sprayers.html
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And the consequences are not pretty…
Human/animal health risks
Contaminated soils & water (including street water runoff)
High cost of pesticides
Beneficial species killed
Effects on animals up the food chain
Pesticide resistance
http://grapes.msu.edu/images/pesticResist.gif
http://www.mindfully.org/Pesticide/2002/Flawed-Frogs-Pesticide-Deformed9jul02.htm
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The ‘New California Garden’ is based on a better strategy
Plant the plants that are ‘programmed’ to be successful in your area – these will:
Be less stressed – and therefore healthier Be prepared to ‘fight’ the natural enemies Attract natural ‘helpers’ in their fight against pests
Plant a variety of species – more like a natural ecosystem (not a monoculture)
Give the plants the appropriate gardening care:
Appropriate levels of water Appropriate (often little to no) fertilizer Protection from other stress & injury
Have an appropriate strategy to deal with true pests
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Many of us have found that just including more native species improves the ‘pest problems’ in the
entire garden
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But you need to have a sound strategy to dealing with certain pests…even on
native plants
And that’s where the concept of Integrated Pest Management (IPM) provides useful guidelines
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Integrated Pest Management (IPM)
"Optimum combination of control methods including biological, cultural, mechanical, physical and/or chemical controls to reduce pest populations to an economical acceptable level with as few harmful effects as possible on the environment and nontarget organisms."
R.L. Hix,CA Agric. Magazine, 55:4 (2001)
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What is Integrated Pest Management?
IPM programs use current, comprehensive information on the life cycles of pests and their interaction with the environment.
This information, in combination with available pest control methods, is used to manage pest damage by the most economical means, and with the least possible hazard to people, property, and the environment.’
http://www.epa.gov/opp00001/factsheets/ipm.htm
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The IPM Pyramid – ‘first do no harm’
Use the least invasive – and often most effective - means first: Prevention – cultural practices Mechanical Controls Naturally occurring biological
controls (native predators)
Consider using non-native predators
Use chemical controls sparingly, as a last resort: Naturally occurring elements Biologics – chemicals made by
plants that are toxic to pests/diseases
Non-biologic pesticides: Insecticides Fungicides Miticides
http://www.team.ars.usda.gov/ipm.html
Non-native predators and chemical
controls have the important drawback of
non-specificity – they kill the good pests
with the bad.
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Some of the benefits of an integrated
approach are as follows:
Promotes natural controls; ‘ecosystem approach’.
Protects human health.
Minimizes negative impacts to non-target organisms.
Enhances the general environment.
Is most likely to produce long-term, beneficial results.
Often is easily and efficiently implemented.
Cost-effective in the short and long-term.
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An IPM system is designed around six basic components
1. Set Action Thresholds Before taking any pest control action, IPM first sets an action
threshold, a point at which pest populations or environmental conditions indicate that pest control action must be taken. Sighting a single pest does not always mean control is needed. The level at which pests will either become an economic threat is critical to guide future pest control decisions.
2. Monitor and Identify Pests Not all insects, weeds, and other living organisms require control.
Many organisms are innocuous, and some are even beneficial. IPM programs work to monitor for pests and identify them accurately, so that appropriate control decisions can be made in conjunction with action thresholds. This monitoring and identification removes the possibility that pesticides will be used when they are not really needed or that the wrong kind of pesticide will be used.
3. Preventive Cultural Practices As a first line of pest control, IPM programs work to manage the
crop, lawn, or indoor space to prevent pests from becoming a threat. These control methods can be very effective and cost-efficient and present little to no risk to people or the environment.
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An IPM system is designed around six
basic components
4. Mechanical controls: Should a pest reach an unacceptable level, mechanical methods are the first options to consider. They include simple hand-picking, erecting insect barriers, using traps, vacuuming, and tillage to disrupt breeding.
5. Biological controls: Natural biological processes and materials can provide control, with minimal environmental impact, and often at low cost. The main focus here is on promoting beneficial insects that eat target pests. Biological insecticides, derived from naturally occurring microorganisms (e.g.: Bt, entomopathogenic fungi and entomopathogenic nematodes), also fit in this category.
6. Chemical controls: Synthetic pesticides are generally only used
as required and often only at specific times in a pests life cycle. Many of the newer pesticide groups are derived from plants or naturally occurring substances (e.g.: nicotine, pyrethrum and insect juvenile hormone analogues), and further 'biology-based' or 'ecological' techniques are under evaluation.
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IPM plan for your garden – a work in
progress
Requires observation & knowledge – specific for your garden
Will vary somewhat with: Yearly weather conditions Maturity of plants New plants
Will be modified based on your previous experiences
Suggestion: keep a garden notebook/journal
http://www.hoodcountymastergardeners.org/Demo_2006/Demo_Construction.html
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Many resources to help you
Books – check out your local library, or add to your own
On-line resources
County Master Gardeners
Other Governmental resources: (see list) U.S.
State & Local
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University of California
Statewide IPM Project (UCIPM)
Goals of the IPM Project are to: reduce the pesticide load in the
environment, increase the predictability and
thereby the effectiveness of pest control techniques,
develop pest control programs that are economically, environmentally and socially acceptable,
marshal agencies and disciplines into integrated pest management program, and
increase the utilization of natural pest controls.
Educational component: Print & on-line resources UC IPM Pesticide Education Program
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Set Acceptable Pest Levels
Find out what pests/ diseases occur in your garden – observation
Learn more about the pests, their effects What are their life-stages What seasons/conditions are
they associated with What plant species are
susceptible
Learn how to determine when action should be taken
http://www.ctahr.hawaii.edu/noni/spiralling%20whitefly.asp
http://waterroots.com/imagespests/whitefly03.jpg
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Monitor & Identify Pests
Base monitoring on garden conditions: temperature & humidity
Look for pests on vulnerable tissues
Shake out the pests, then view with magnifying glass
Decide if action is needed Suggestion: keep a log of dates,
conditions in your garden journal
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Prevention/Cultural Practices are the first
line of defense against pests
Cultural practices: just good old garden management practices
Providing alternate hosts for pests No monoculture Preventing over-wintering Sanitation Proper water & nutrient management Correct watering Physical barriers Pruning to improve air circulation Weeding Mulching
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Criteria for selecting a treatment
strategy are:
1. Least hazardous to human health
2. Least disruptive of natural controls
3. Least toxic to non-target organisms
4. Most likely to be permanent
5. Easiest to carry out safely and effectively
6. Most cost-effective
7. Most site-appropriate
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Pest challenges vary with the season….
Warmer weather & new growth – spring/early summer Sucking insects Chewing insects Gall & Blister Mites
Warm weather – summer/fall Foliage fungal diseases Borers (insects) Root/stem rots
(fungal/bacterial)
Cool, wet weather – winter/early spring Mollusks Anthracnose (fungal)
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Sticky (Bush) Monkey Flower -Mimulus/Diplacus aurantiacus
http://www.baynatives.com/plants/Mimulus-aurantiacus/
Scarlet Monkeyflower Musk Monkeyflower
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Sucking insects
Definition: Insects that insert their mouthparts into the sugary phloem (conducting tissue) & suck the ‘sap’
Examples: Aphids Mealy Bugs Whiteflies Psyllids Scales Leafhoppers
Damage: Often confined to the young, succulent
growth (leaves, shoot-tips and buds Tissues appear puckered or crinkled
Monitoring: watch for: Signs of the insects themselves –check
particularly undersides of leaves, other protected areas
Ants – tend to be ‘nurse’ species Abnormal plant growth
http://scienceblogs.com/neurophilosophy/Ant_cultivating_aphids.jpg
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Any perennial or shrub/tree with fresh
new foliage can attract sucking insects
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Aphids: where there’s one there are many…..
Often called plant lice, are small, soft-bodied insects.
They range in color from black to green to yellow.
Their numbers may greatly increase in a short time and crowding stimulates the production of winged forms.
They may cover the entire surface of a leaf or stem.
They (and other sucking pests) can be vectors of plant viruses (crop & ornamental plants).
They can also weaken plants, making them susceptible to other diseases
http://notexactlyrocketscience.files.wordpress.com/2006/08/aphid-sap.jpg
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Aphids – Ugly but not usually murderers...
Preventive cultural practices: Control ants Control weeds –
particularly Brassica species
Mechanical Controls: Blast off with a stream of
water Use sticky strips around
trunks to manage ants
Biological Controls: Lady bugs; Lacewings
Chemical controls: Insecticidal Soap is usually
adequate
http://ipm.ncsu.edu/cotton/insectcorner/photos/aphid.htm
http://pmo.umext.maine.
edu/factsht/Suck.htm
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Whiteflies
Monitoring: By placing yellow sticky cards in greenhouse &
other vulnerable environments Periodic inspection of undersides of leaves of
susceptible species Preventive cultural practices:
Don’t purchase infested plants Control ants Encourage natural predators
Mechanical Controls: Yellow sticky traps (early in infestation) Blast off with stream of water Hand-remove infested leaves Vacuum them up with hand vacuum
Biological Controls: Ladybugs, Lacewings, parasitic wasps & mites Songbirds
Chemical controls: Insecticidal Soap Chemical pesticides usually not very helpful –
resistance quickly develops
http://ipm.ncsu.edu/cotton/InsectCorner/photos/other.htm
http://agriculture.gov.bb/media/plant_protection/Whiteflies2.JPG
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Monitor particularly on citrus and vegetable crops (and plants near them)
Mechanical methods and encouraging natural enemies offer best chance for control
http://cekern.ucdavis.edu/Entomology/Woolly_Whitefly_Monitoring_in_Kern_Cou
nty.htm
Wooly Whitefly on Citrus
Ash Whitefly (Siphoninus phillyreae)
can attack Toyon & other natives
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Mealybugs Females feed on plant sap, normally in roots or
other crevices. They secrete a powdery wax layer (therefore the name mealybug) used for protection while they suck the plant juices.
Monitoring: Check stem axils & bottoms of plant stems for
insects Act immediately when you see them to control
infestation
Preventive cultural practices: Insect new plants – remove pests Control ants (which protect Mealybugs) Encourage natural predators
Mechanical Controls: Remove by hand & destroy Apply rubbing alcohol with a Q-tip or cotton
ball; destroys insects & egg masses [note: try on small area first – may damage plant]
Biological Controls: Lady Bug, Lacewings, parasitic wasps –all natural
Chemical controls: Insecticidal Soap or horticultural oils
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Controlling aphids, whiteflies & Mealybugs is an
important ‘cultural practice’ for preventing other diseases
Mealybugs are similar to whiteflies and aphids: they produce large amounts of waste product (honeydew) which coats plants and surrounding surfaces.
This sticky layer is a perfect growth medium for a black fungus commonly known as "sooty mold".
This mold damages plants by covering leaves and reducing light available for photosynthesis.
Sooty Mold
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True Bugs
Many are actually beneficial predators
Preventive cultural practices: Encourage healthy plants
Chemical controls: not recommended in most cases
http://pmo.umext.maine.edu/factsht/Suck.htm
Milkweed Bug
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Good natural enemies are there – just
plant species that will attract them
Green Lacewing
Common generalist predator
Kills: mealybugs, psyllids, thrips, mites, whiteflies, aphids, small caterpillars, leafhoppers, and insect eggs
Use common pesticides & you’ll kill this beneficial insect
Plant species in the Rose & Buckthorn (Ceanothus) families to provide food for Lacewings
Green Lacewing
You will need to learn about
the common beneficial
insects in order to recognize
and attract them
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Attract these
beneficial insects
By planting these species
Bigeyed bug Native grasses Polygonum sp. (Silver Lace Vine)
Hoverflies Achillea sp. (Yarrow) Asclepias fascicularis (Narrowleaf Milkweed) Baccharis sp. (Coyote brush, Mulefat) Ceanothus sp. (California Lilac) Eriogonum sp. (Buckwheat) Prunis ilicifolia (Hollyleaf Cherry)
Lacewings Ceanothus sp. (California Lilac) Prunus ilicifolia (Hollyleaf Cherry)
Lady beetles Achillea sp. (Yarrow) Asclepias fascicularis (Narrowleaf Milkweed) Atriplex sp. (Quailbush, Saltbush) Ceanothus sp. (California Lilac) Native grasses Rhamnus californica (Coffeeberry) Salix sp. (Willow)
http://www.stopwaste.org/home/index.asp?page=402
Copyright © 2007 Ron Hemberger
http://www.kunafin.com/lacewings.htm
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Know all life phases of
beneficial insects
Don’t use pesticides that will kill the beneficial insects
Larval stage – though ugly - is often the ‘eating’ stage
Look closely at the insects (use a magnifying glass) – what are they eating (plant or insect)
http://www.ipm.ucdavis.edu/PMG/NE/convergent_lady_beetle.html
http://www.ipm.ucdavis.edu/PMG/NE/brown_lacewing.html
http://upload.wikimedia.org/wikipedia/commons/2/2a/Sa_lady-beetle-larva.jpg
Lacewing Life Cycle
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Attract these
beneficial insects
By planting these species
Minute pirate bug
Achillea sp. (Yarrow) Baccharis sp. (Coyote brush, Mulefat) Eriogonum sp. (Buckwheat)
Parasitic & Predatory Wasps
Achillea sp. (Yarrow) Aesclepias fascicularis (Narrowleaf Milkweed) Eriogonum sp. (Buckwheat)
Tachnid flies Achillea sp. (Yarrow) Eriogonum sp. (Buckwheat) Heteromeles arbutifolia (Toyon) Rhamnus californica (Coffeeberry)
http://www.stopwaste.org/home/index.asp?page=402
http://www.ipm.ucdavis.edu/PMG/NE/minute_pirate_bug.html
http://www.ipm.ucdavis.edu/PMG/NE/tachinid_flies.html
Minute Pirate Bug
Tachnid Fly
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Western Yarrow – Achilla millefolia
J.S. Peterson @ USDA-NRCS PLANTS Database
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Why Yarrow makes a good lawn substitute
Spreads quickly, giving good cover
Super for banks and other areas that can’t easily be mowed
Spreading habit inhibits weeds
Can be mowed – occasionally and on high setting w/ rotary mower
Companion plant – attracts beneficial insects, repels others
Does well on poor, dry, sandy soils where other plants grow poorly
http://www.dgsgardening.btinternet.co.uk/yarrow.JPG
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Levels of Control
1. Cultural control is a preventative measure using fertilization, plant selection, and sanitation to exclude problematic pests and weeds.
2. Physical control is another preventative strategy. It includes, pest exclusion; creating barriers; modifying conditions such as temperature, light and humidity; trapping; and manually weeding. Foods and beverages should be eaten and stored only in designated areas.
3. Biological control makes use of a pest's natural enemies. This strategy introduces beneficial insects or bacteria to the environment or, if they already exist, provides them with the necessary food and shelter and avoids using broad-spectrum chemicals that will inadvertently kill them.
4. Chemical control is used after all other control strategies are deemed inappropriate or ineffective. Target-specific, low-toxicity pesticides should be applied in a manner that will maximize the effectiveness of pest management and minimize the exposure to humans and other non-target species. Spot treat if possible to reduce exposure.
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Smothering and suffocation agents - mild
Insecticidal Soap
It works on contact by breaking down the target pest’s cuticle (waxy covering) — promoting dehydration and, ultimately, death.
Short period of action (48 hours)
Non-targeted – kills both beneficial insects as well as pests
Best use: judicious, small-scale spot applications
Safer’s Insecticidal Soap (the most common brand), is used indoors or out, is effective on aphids, cabbageworms, earwigs, flea beetles, lace bugs, leafhoppers, mealybugs, psyllids, sawfly larvae, scale crawlers, squash bugs, thrips, spider mites, whiteflies, and more.
http://ecx.images-amazon.com/images/I/51z2EPV-efL._SL500_AA280_.jpg
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Smothering and suffocation agents - mild
Horticultural Oil
Coating pests with horticultural oil blocks the passage of air through their spiracles (breathing holes), thus killing (suffocating) them.
Used on dormant plants (see label for specific product)
labeled for use against overwintering eggs of European red spider mites, scale insects, apple aphids (not rosy aphids), bud moths, leafrollers, red bugs, codling moth larvae, pear psylla (adults), blister mites, galls, whitefly nymphs, and mealybugs.
http://greenmethods.com/site/products/biorationals/3/#ip
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Sucking insects of spring/summer: review
Monitor Periods of new foliage/rapid growth Monitor at least weekly Look particularly at undersides of leaves, young branch tips, flower
buds – be sure to use a magnifying glass
Cultural Practices Blast affected area with water Hand remove Encourage natural predators Control ants
Biological Controls Beneficial insects – your best line of defense
Chemical controls Not usually needed (except for very bad infestations – not often seen
with native plants) May kill beneficial insects – so use very sparingly Try least toxic: Insecticidal soap
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Ah, Summer….. the time of dusty leaves & over-watering
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10 years old. Almost no water other than a dust wash off every month or so.
Arctostaphylos 'Carmel Sur’ in foreground, Toyon and Western Redbud behind.
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Challenges of the dry season
Dry, dusty foliage
Hot, muggy (or foggy) days
Appropriate watering: How frequently
How much at any one time
How to water: overhead, drip/trickle
What time of day to water The stage is set for a different
cast of garden pests
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Toyon/California Christmas Berry – Heteromeles arbutifolia
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Natives in the Rose Family (Rosaceae)
Shrubs
Chamise - Adenostoma fasciculatum Mountain Mahogonies - Cercocarpus species Toyon - Heteromeles arbutifolia Creambush - Holodiscus discolor Ironwoods - Lyonothamnus floribundus Holly-Leafed & Catalina Cherries - Prunus ilicifolia CA Wild Rose - Rosa californica CA Blackberry - Rubus ursinus
Smaller perennials
Pacific silverweed - Argentina egedii Strawberries - Fragaria species Wedgeleaf Horkelia - Horkelia cuneata
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Common pests of Rose Family (think garden roses)
Pests of new foliage Sucking insects
Pests of summer Pests associated with dust (mostly
insects) Pests associated with warm, moist
conditions (mostly fungal but some bacterial/viral)
Diseases associated with cool, wet conditions: Fungal diseases (foliage & root)
Rosa CA vs. non-native roses It is relatively pest and disease free,
except if the plant is subject to overhead irrigation, poor air circulation and humid conditions in the shade.
Insect pests are usually not a problem with such a hardy plant and with so many “beneficials” around.
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Leafhoppers & Sharpshooters
Leafhoppers are small, green, wedgeshaped insects that attack many garden, forage and fruit crops. They suck out plant juices causing yellowing, leaf-curling and stunting.
Leafhoppers are often responsible for the spread of plant pathogens especially viruses and phytoplasmas
Preventive cultural practices:
Mechanical Controls: blast of water from a garden hose Removing infected lower leaves Dusting plants lightly with
diatomaceous earth
http://pmo.umext.maine.edu/factsht/Suck.htm
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Leafhoppers & Sharpshooters
Biological Controls:
Predatory insects such as mantids and dragonflies
Spiders, green lacewings (Chrysopa spp.), minute pirate bugs (Orius spp.), lady beetles (Hippodamia spp.), and predaceous mites.
Small parasitic wasps in the genus Gonatocerus
Chemical controls:
Narrow range oils, insecticidal soaps, or kaolin clay
rotenone, carbaryl, malathion or methoxychlor
http://pmo.umext.maine.edu/factsht/Suck.htm
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Glassy-winged Sharpshooter – reportable pest
Carry the bacterium, Xylella fastidiosa, that causes Pierce’s Disease – a serious threat to CA grape industry
X. fastidiosa also causes
almond leaf scorch, phoney peach disease, alfalfa dwarf, oleander leaf scorch and citrus variegated chlorosis.
Report to County Ag.
Service if found in new areas
http://www.slocounty.ca.gov/Assets/AG/assets/GWSS2.gif
Adults are about 1⁄2 inch long
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Pierce’s Disease: many native plants are
alternate hosts
Aesculus californica Artemisia douglasiana Heteromeles arbutifolia Juglans californica Mimulus aurantiacus Oenothera hookeri Philadelphus lewisii Populus fremontii Quercus spp. Rhammus californica Rosa californica Salix spp. Sambucus spp. Vitis californica
Blue Elderberry
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Thrips Tiny insects with fringed wings. They feed on pollen and tender plant tissue, rasping the tissue and sucking the exuding sap.
The leaves take on a silvery appearance after the thrips feed, and plants become stunted and deformed.
Thrips are usually a pest of seedling plants but may attack plants in any stage. They attack an extremely wide variety of woody plants.
Certain thrips species are beneficial predators that feed only on mites and other insects
Monitoring:
Thrips often feed within buds and furled leaves. Their damage is often observed before the thrips are seen.
Discolored or distorted plant tissue or black specks of feces around stippled leaf surfaces are clues that thrips are or were present.
Look carefully for the insects themselves before taking action. Severe infestation foliage looks silver-spotted
Thrips are poor fliers but can readily spread long distances by floating with the wind or being transported on infested plants.
http://pmo.umext.maine.edu/factsht/Suck.htm
http://mrec.ifas.ufl.edu/LSO/images/Thrips/ffa2-34.jpg
http://www.gardenseeker.com/plant_pests_problems/plant-pests/thrips_storm_flies.htm
© Project SOUND
Thrips – mostly just ugly…
Healthy woody plants usually tolerate thrips damage; however, high infestations on certain herbaceous ornamentals and developing fruits or vegetables may justify control
Preventive cultural practices: Practices to conserve natural predators;
decrease dust, no pesticides Pull weeds Prune and destroy infected branches
Mechanical Controls: Blast of water from a garden hose
Biological Controls: Many natural predators
Chemical controls: thrips activity does not usually warrant the use of insecticide sprays Narrow-range oil, neem oil, pyrethrins combined
with piperonyl butoxide (Garden Safe Brand Multi-purpose Garden Insect Killer, Spectracide Garden Insect Killer)
Malathion or rotenone only for severe problems
http://chillithrips.tamu.edu/
http://virtual.clemson.edu/groups/hort/homeh
ort/images/thrips.jpg
Toyon Thrips
© Project SOUND
Gall & Blister Mites: ugly but not killers
Cause blistered leaves or galled twigs on many landscape plants including alder, aspen, baccharis, beech, elm, grape, linden, maple, and walnut
Monitoring:
Misshapen leaves
Preventive cultural practices:
Remove damaged leaves
Mechanical Controls:
Remove damaged leaves
Live oak erineum mites
Baccharis gall
© Project SOUND
Spider Mites are tiny
Not insects, but closely related to ticks and chiggers. They suck out juices from leaves and stems, causing plants to become deformed or have a bronze or yellow appearance
Heavy infestations can cause leaf and bud drop, serious stress and death of the plant.
Damaged areas typically appear marked with many small, light flecks – over slightly cobwebby - giving the plant a somewhat speckled appearance.
Activity peaks during the warmer months; Dry, dusty conditions favor all spider mites
Monitoring: Usually plant damage—stippling or yellowing of
leaves Look for webbing underneath leaves Shake mites onto paper & observe with hand
lens
http://pmo.umext.maine.edu/factsht/Suck.htm
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7405.html
© Project SOUND
Spider Mites: prevention is best
Preventive cultural practices: Wash dust off leaves in summer Don’t use insecticides (carbaryl (Sevin);
imidacloprid (Merit, Marathon) ) that kill natural predators; severe infestations often follow insecticide use!
Mechanical Controls: blast of water from a garden hose 1:1 mixture of alcohol and water [test on small area] Plant isolation
Biological Controls: Small, dark-colored lady beetles known as the
"spider mite destroyers" Minute pirate bugs, big-eyed bugs (Geocoris
species) and predatory thrips Parasitic spider Mites
Chemical controls: not during hot weather or for water stressed plants – test first on a few leaves Insecticidal soap Horticultural oils (Sunspray) Sulfur
http://pmo.umext.maine.edu/factsht/Suck.htm
Few insecticides are effective for spider mites and many even aggravate problems
© Project SOUND
Chewing insects are
also active in summer
Definition: Chewing insects eat plant tissue such as leaves, flowers, buds, and twigs.
Indications of damage: uneven or broken margins on the leaves, skeletonization of the leaves, and leaf mining.
The damage they cause (leaf notching, leaf mining, leaf skeletonizing, etc.) will help in identifying the pest insect.
Examples: beetle adults or larvae, moth larvae (caterpillars) many other groups of insects.
Cabbage Looper
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Is it a sucking or a chewing pest?
Sucking pests, such as aphids, leafhoppers, scale insects and whiteflies, produce these symptoms:
• Discoloration (yellow or brown) and necrotic (dead) spots on leaves or petals;
• Wilted appearance of plant or plant parts; • Curled, malformed leaves and petals; and • Shiny, sticky “honeydew” or black-colored
coating of sooty mold.
Chewing pests, such as caterpillars, beetles, grasshoppers and leaf-cutter bees, produce these symptoms:
• Holes in foliage or stems; • Discolored areas on the surface or margins
of leaves or petals; • Severed stems, leaves or buds or wilting of
stem or cane (limb girdling); • Wilting of plant (root damage by white
grubs or other root feeders); and • Semicircular holes in leaf margins (leaf-
cutting bees).
© Project SOUND
Botanical pesticides: natural but not
harmless for control of chewing insects
Pyrethrum is extracted from the flowers of a chrysanthemum grown in Kenya and Ecuador. It is one of the oldest and safest insecticides available. Mode of action — Pyrethrum (and synthetic pyrethrum) paralyze insect’s nervous system. Used for – aphids, scale insects, spider mites, thrips, caterpillars and many other leaf-
feeding pests
Rotenone or rotenoids are produced in the roots of two genera of the legume family: Derris and Lonchocarpus (also called cubé) grown in South America. Mode of action: shuts down cellular metabolism It is both a stomach and contact insecticide; toxic to many species of insects in many
different insect orders (caterpillars, beetles, flies, etc.). Mild human toxicity; ? Risk for Parkinson’s Disease
Eugenol (Oil of Cloves) and Cinnamaldehyde (derived from Ceylon and Chinese cinnamon oils). Mode of action – similar to Pyrethrum Used for: chewing insects like beetles – but general insecticide
Nicotine is extracted by several methods from tobacco Mode of action – nervous system conduction; convulsions, death effective against most all types of insect pests, but is used particularly for aphids and
caterpillars--soft bodied insects.
EcoSMART™ plant oil-based pesticides
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Neem Oil/ Azadiractin
Neem oil extracts are squeezed from the seeds of the neem tree and contain the active ingredient azadirachtin
Rather sensational insecticidal, fungicidal and bactericidal properties, including insect growth regulating qualities.
Mode of action--Azadirachtin disrupts molting by inhibiting biosynthesis or metabolism of ecdysone, the juvenile molting hormone.
Used for: Azatin® is marketed as an insect growth
regulator, and Align® and Nemix® as a stomach/contact insecticide for greenhouse and ornamentals.
Many leaf chewing insects including Gypsy moth larvae, imported cabbage worms, leafminer species’ larvae and pupae, various leafrollers, various loopers, grasshoppers, beetles, mealybug species’ immatures, sawfly larvae, sweet potato and silverleaf whitefly immatures, and webworms
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Read & follow
directions
http://rayssupplycompany.com/index.php?main_page=index&manufacturers_id=42
Mix pesticides according to label instructions. Don’t use more or less concentrate than the label recommends. Mix only as much material as you need for the application.
Wear protective clothing as specified on the label.
Label a set of mixing and measuring tools that are used only for insecticides and fungicides, and store them with the products.
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More pesticide safety tips
Keep pets and people away from the area where you store, mix, and apply pesticides. Stay away from a treated area for as long as the label directs.
Do not spray on a windy day or when air temperatures will be above 85°F before the spray solution dries.
Clean equipment and mixing tools as soon as you finish spraying.
Dispose of pesticides properly
After spraying, change your protective clothing and bathe. Wash the clothes you were wearing separately from your regular laundry.
Keep records of where and when you sprayed, what pesticide you used, and how much you used. Give the treatment time to work, then evaluate and record your results.
http://www.gemplers.com/img/pesticide-storage-area-126066.jpg
http://www.ipm.ucdavis.edu/WATER/U/storedispose.html
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Black Spot - Diplocarpon rosae fungus
Occurs during warm, damp/humid weather; spores overwinter in infected canes & fallen leaves
Preventive cultural practices: Provide good air circulation, appropriate sunlight conditions Don’t over-water; no overhead irrigation Remove & dispose of infected leaves; don’t handle plants when foliage is wet Cut back & dispose of infected canes; dispose of fallen leaves
Chemical controls: fungicides – copper, sulfur & Neem Oil
http://www.extension.umn.edu/distribution/horticulture/DG1163.html
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Currants & Gooseberries – Ribes spp
Pink-flowering Currant - Ribes sanguineum
White-flowering Currant - Ribes indecorum
Chaparral Currant - Ribes malvaceum
Catalina Perfume - Ribes viburnifolium
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Common pests/diseases of Ribes species
Fungal Diseases Leaf Spot or
Anthracnose
Cane Blight
Powdery Mildew
Rusts
Virus and Virus-like Diseases
Insects & Mites Sucking insects
Gall formers
Stem borers
http://www.ars-grin.gov/cor/ribes/ribsymp/ribsymp.html
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The ‘Disease Triangle’ – the key to
understanding plant pests & diseases
Proper environment Warm, wet conditions
Overhead watering
Poor air circulation
Cultural (prevention) controls are mostly about making the environment inhospitable
Currant
Fungal species
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Powdery Mildew - Sphaerotheca pannosa
fungus
http://www.extension.umn.edu/distribution/horticulture/DG1163.html
Susceptible: Rose family, Dogwoods, Honeysuckles, Sycamores, Willows, Sunflower Occurs during warm, damp/humid weather; spores overwinter in infected wood &
fallen leaves Preventive cultural practices:
Provide good air circulation, appropriate sunlight conditions Don’t over-water; no overhead irrigation Remove & dispose of infected leaves Cut back & dispose of infected branches; dispose of fallen leaves
Chemical controls: fungicides – copper, sulfur, horticultural oils & Neem Oil
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Rusts – large group of foliage
fungi attacking many plant
species
Occur during warm, damp/humid weather; spores overwinter in infected wood & fallen leaves
Preventive cultural practices: Provide good air circulation,
appropriate sunlight conditions Don’t over-water; no overhead
irrigation Remove & dispose of infected
leaves Cut back & dispose of infected
branches; dispose of fallen leaves
Chemical controls: fungicides – copper, sulfur, horticultural oils & Neem Oil
http://gardeningwebguide.com/GardeningBlog/category/garden-pests/
http://www.omafra.gov.on.ca/english/crops/pub360/notes/rasporustf1.jpg
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Natural Compounds as preventive measures: fungal diseases
Example: Copper-Sulfate Copper-Sulfate Spray or Dust Copper
Bordeaux substitute is an organic fungicide containing 7% copper sulfate (metallic)
Effective in preventing a wide range of various blights, spots, certain rots, downy and powdery mildew, leaf blister, anthracnose, scab, stem canker, Septoria spp. and Stemphylium spp. leaf molds and more.
No insecticidal qualities, and will not burn plants.
Must be applied early (when plants dormant)
Appropriate cultural practice for fungal prone species like Currants
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Fungal Canker
Diseases
Cause: several types of fungi that invade bark injuries & infect connective tissues of trunk
Monitoring: a killed area or blister on the bark, a branch or the trunk of an infected tree. May ooze.
Preventive cultural practices: Promote overall tree health;
don’t over-fertilize Prevent trunk/branch
wounds Proper pruning; dormant
season Call an experienced arborist
or County Dept. of Ag.; early treatment can help
http://www.extension.umn.edu/projects/yardandgarden/ygbriefs/p-cankermaple.html
http://www.ext.colostate.edu/Ptlk/1407a.html
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Fireblight - Erwinia amylovora
Bacteria that infects the new spring growth in Rose family
During warm, wet weather the bacteria ooze in brown droplets from cankers and are spread by pollinators and splashing water to the flowers and then to twigs.
Verify the presence of fireblight by peeling back newly infected bark-the wood will have a reddish-brown discoloration.
Prune diseased wood back at least 6 inches into healthy tissue. Entire branches (even whole plants) may need to be removed.
Do not put prunings into a compost pile; dispose of them in the green waste.
Sterilization of the pruning instruments between each cut with a 10% bleach solution.
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7414.html
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Mature trees, when stressed, are
susceptible to stem-boring insects
Drought stress can be avoided by supplemental winter watering when needed
goldspotted oak borer (GSOB)
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Stem Borers: Longhorned borers, bark &
ambrosia beetles, clearwing moths, twig girdlers,
flatheaded borers
Willows, Cottonwood/Poplar, Sycamore, Oak, Juniper, Pine, Ceanothus, currants
Monitoring: particularly for old or stressed trees/shrubs Bark staining Bore holes Frass; pupal cases [Clearwing Moths]
Preventive cultural practices: Encourage vigorous, healthy plants Prevent stem/root injury removing weakened, injured, dying, and
dead trees Mechanical Controls: Biological Controls:
Parasitic nematodes Chemical controls:
http://www.fs.fed.us/r5/cleveland/projects/projects/oa
k-borer/
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Diseases that affect soils
More common in areas previously used for agriculture, vegetable gardening, palm trees
Caused by fungal or bacterial pathogens in the soils
Enter plants via the roots
Very difficult to control – require soil sterilization
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Blights & Branch Die-back
Causes: Verticillium wilt—Verticillium fungi Fusarium wilt - Fusarium fungi Root Rot fungi
Susceptible: Strawberries, caneberries Vegetable crops (tomato) Woody trees (many)
Monitoring: Symptoms: Decline in twig and leaf growth. Dieback in individual twigs and
branches. Foliage becomes light green to chlorotic and then may scorch by midsummer. A discoloration of the inner bark may occur.
Leaves on one or more branches suddenly wilt, turn light tan, and die. Dead leaves generally remain on the tree throughout the growing season.
http://www.ipm.ucdavis.edu/PMG/GARDEN/FRUIT/DISEASE/verticilliumwil.html
© Project SOUND
Blights & Branch Die-back
Preventive cultural practices:
Keep plants healthy; don’t stress by over- or under watering
Remove Verticillium-susceptible weeds, such as lamb's quarters, amaranth (pigweed), nightshade
Remove and dispose of affected plants, including roots
Solarize affected soils
Chemical controls: consult a licensed arborist or County Agent
Oak Twig Blight
http://www.ipm.ucdavis.edu/PMG/GARDEN/PLANTS/DISEASES/oak
brdieback.html
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Root, collar & crown rots
A large number of root rots are caused by members of the water mould genus Phytophthora.
Favored by high soil moisture and soil temperatures in poorly drained soils.
More common in soils with prior Azaleas, Avocado, Citrus
Monitoring:
Plants wilt at midday and may recover at night (ultimately, plants yellow and die).
In trees, sparse growth and slow decline.
Feeder roots have blackened tips, brown streaks or appear to be rotting.
Mushrooms around tree base indicate final stages.
http://www.ca.uky.edu/agcollege/plantpathology/ext_files/PPFShtml/PPFS-OR-W-5.pdf
http://www.ces.ncsu.edu/depts/pp/notes/oldnotes/odin13/od13a.htm
Brown streaks on roots
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Root/collar/crown rots
Preventive cultural practices:
Proper drainage and irrigation, particularly in clay soils; consider berming to increase drainage
Choose species that can tolerate poorly-drained soils
Never cover root collar with dirt or mulch
Don’t damage roots
Buy only healthy plants
Weed around the tree/shrub
Remove and destroy infected plants, roots
Chemical controls: Call experienced, licensed arborist for infected trees
http://ag.arizona.edu/PLP/plpext/diseases/trees/Ash/GRR2.html
http://www.ces.ncsu.edu/depts/pp/notes/oldnotes/odin13/od13a.htm
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Sudden Oak Death Syndrome - Phytophthora ramorum
Kills CA native oaks and other trees/shrubs in N. CA & OR (for now)
Toyon (Heteromeles arbutifolia), Coffeeberry (Rhamnus californica), CA Buckeye and Honeysuckle (Lonicera hispidula) and others are susceptible. Disease symptoms have not been well characterized on these hosts at this time.
Leaf lesions are characteristically round with a bulls-eye appearance of alternating light and dark rings
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Evergreen huckleberry Vaccinium ovatum
California buckeye Aesculus californica
A number of other native broad-leaf species harbor Phytophthora ramorum in California and Oregon (See the complete list in Part 1.). Little is known about the role of these species in the life cycle and spread of the disease. The pathogen is difficult to culture from many of these species, and is difficult to diagnose because of the presence of other foliar diseases.
Toyon Heteromeles arbutifolia
Bigleaf maple Acer macrophyllum
California honeysuckle Lonicera hispidula
Pacific madrone Arbutus menziesii
Wood rose Rosa gymnocarpa
All photos: Garbelotto Lab, UC Berkeley http://www.suddenoakdeath.org/ppt/Virtual%20Training%20Part%202.ppt#324,8,Slide 8
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And now we’re back to the rainy season…
….with it’s own unique set of pest challenges
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Snails & slugs
http://extension.oregonstate.edu/news/images/snail.jpg
http://i.dailymail.co.uk/i/pix/2008/06/18/article-1027544-01A4B50C00000578-51_468x315.jpg
http://farm2.static.flickr.com/1257/942909073_87997125e8.jpg?v=0
Preventive cultural practices: Don’t over-water Remove dead leaves from
ground
Mechanical Controls: Mechanical picking Trapping: under boards or
newspapers Pans of beer or sugar water Copper bands (for tree
trunks)
Biological Controls: Encourage birds, toads
Chemical controls: ‘Non-toxic’ Iron phosphate
snail bait – ‘Sluggo’ brand
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Sycamore anthracnose - Gnomonia leptostyla
The only serious disease of sycamores; will not kill
the tree.
Common in cool wet weather of spring.
Monitoring: First symptoms appear on young leaves as they unfold. Older leaves turn brown, and dead areas occur along
the leaf veins. Brown areas eventually include the whole leaf.
The ends of twigs may be killed back 8 to 10 inches. Cankers may develop on the tree trunk and main
branches
Preventive cultural practices: Proper tree spacing and pruning to promote good air
circulation Gather and destroy all fallen leaves and twigs. Prune out all infected twigs and branches and destroy
them. Remove the dead, cankered tissue down to healthy wood.
Dry winters weaken trees, increasing the effects of diseases. To reduce this problem, water trees once a month during dry winters.
Chemical controls: Chemical sprays normally are not necessary to control
anthracnose
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So, go out to your garden and get to know it’s insects