Horticulture 159 Project - Spring 2021

1. Pest Assignment
Kayla Lamore (Falk) -
Horticulture 113
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2. Simple Insect
Metamorphosis:
Grasshopper
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3. 3
Simple Insect
Metamorphosis:
Grasshopper

4. Complete Metamorphosis:
Monarch Butterfly
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5. Complete Metamorphosis:
Monarch Butterfly
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6. Mite vs. Insect Damage
Mites have sucking mouthparts and will bite
leaves other plant parts and suck out nutrients.
Symptoms typically appear as discolored and
mottled leaves. Mites are not able to be seen by
the naked human eye.
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7. Mite vs. Insect Damage
Alternatively, insects have many different styles
of mouthparts. Two of the most common:
- Chewing: damage typically includes
tearing, notched or ragged leaves, holes in
fruits and seeds, girdled stems and chewed
off roots.
- Piercing-sucking: penetrating plant tissues
and sucking out nutrients. Causes
symptoms such as yellowed leaves, galls
and misshapen fruit.
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8. Insects Vectoring Disease:
Asters Yellow
Symptoms of asters yellows are often mistaken for
damage due to herbicide exposure. Infected plants
are typically stunted and twisted, with foliage that
is yellow or red. Infected plants are often sterile.
Floral parts that are normally brightly colored
may remain green, and petals and sepals may
become puckered and distorted.
In purple coneflower, secondary flower heads
(often in a cluster) may emerge from the primary
flower head. In marigolds, flowers are often leafy
and a muddy green-orange color. Infected carrots
have red leaves and form taproots with tufts of
small, white “hairy” roots. These roots often have
a bitter taste.
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Source: UW-Madison Horticulture Extension

9. Insects Vectoring Disease:
Asters Yellow
Asters yellow is vectored by the aster leafhopper,
which moves the phytoplasma from plant to plant.
Other plants affected by asters yellow:
- Celery
- Lettuce
- Potato
- Cucumber
- Pumpkin
- Squash
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10. Hemiptera - Stink bug
Common Name: Stink bug, Brown Marmorated Stink
Bug, BMSB
Damage to Apples: Early-season feeding on developing
apples results in a surface blemish that is often referred
to as “cat-facing” and makes the fruit unmarketable.
Later-season feeding on apples leads to water-soaked or
necrotic (i.e., dead) areas that make the fruit more
prone to invasion by rot organisms. Unfortunately,
symptoms from late-season feeding may not show up
until four to five weeks after fruit is placed in cold
storage. Damage due to BMSB on other small fruit
crops is similar to that on apples, but may also include
fruit drop. (Source: UW Extension)
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11. Hemiptera - Stink bug
Mouthparts: Penetrating, sucking - BMSB mouthparts
consist of a long beak, which houses the stylets inside.
During feeding, the stylets extend out of the beak and
penetrate the plant tissue.
Metamorphosis: Simple
Source: Insights into the Saliva of the Brown Marmorated Stink
Bug Halyomorpha halys (Hemiptera: Pentatomidae) by Michelle
Peiffer & Gary W Felton
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12. More than 270 plant species have been reported as hosts for cicadas.
Some of the tree species preferred by cicadas include apple, ash,
beech, cherry, dogwood, hawthorn, hickory, magnolia, maple, oak,
peach, and pear. In addition, preferred flowers, vines, and shrubs
include arborvitae, black-eyed Susan, grape, hollies, junipers,
raspberry, rhododendron, rose of Sharon, spirea, and viburnum.
Periodical cicadas can damage trees both above and below ground.
The most obvious damage is caused when cicadas lay eggs on small
twigs, leading to a splitting of twigs that eventually causes death to
the branches. This injury is called “flagging”. Large, established trees
can withstand considerable flagging. However, flagging can be very
serious on young trees (< 4 years old), because these trees have many
branches that are of a size (1⁄4 to 1⁄2 inch diameter) preferred by
cicadas. Damage is also caused by immature cicadas (nymphs) that
suck sap from the roots of plants. Prolonged feeding by nymphs may
reduce plant growth and fruit production, and ultimately lead to
death.
Cicadas do not bite readily or sting, and they have no known toxic
chemicals that they release. However, they are considered a nuisance
because of their abundance and loud, deafening noise.
Homoptera - Cicada
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Source: UW Extension

13. Homoptera - Cicada
Mouthparts: Piercing and sucking
Metamorphosis: Complete
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14. Coleoptera - Viburnum
Leaf Beetle
Viburnum leaf beetles feed exclusively
on and damage viburnum species.
In Wisconsin, an isolated infestation of
VLB was discovered in Dane County in
2009, but was successfully eradicated. In
2014, VLB was detected on a mature
viburnum bush in northern Milwaukee
County and other nearby infestations
were detected in June 2015. At present,
VLB infestations are known from
Kenosha, Milwaukee, Ozaukee,
Washington, Waukesha, and Winnebago
Counties.
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15. Coleoptera - Viburnum
Leaf Beetle
Mouthparts: Chewing
Metamorphosis: Complete
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16. Lepidoptera - Gypsy Moth
Gypsy moth caterpillars have been reported
to feed on over 600 species of trees and
shrubs. Preferred hosts include aspen,
birch, crabapple, hawthorn, linden,
mountain ash, oak, sweet gum, and willow.
Some deciduous trees (e.g., dogwood, green
ash, honey locust, silver and red maple, tulip
tree, and white ash) are resistant. Typically,
most evergreen trees are also resistant.
However, blue spruce and white pine are
susceptible. Feeding damage frequently
results in severe and/or complete
defoliation; decreasing the energy reserves
of the tree. On rare occasions, trees that are
defoliated by gypsy moth are killed. More
typically, trees recover and produce new
leaves in July
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17. Lepidoptera - Gypsy Moth
Mouthparts: As with most
lepidoptera, chewing are present
in the caterpillar stage; sucking
are present in the adult stage.
Metamorphosis: Complete
Small larvae spin silk from glands in
their mouthparts and hang from
branches high up in trees.
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18. Acari - Spruce Spider Mite
Spruce spider mites can attack a number of conifers
including spruce, hemlock, white cedar (arborvitae), larch,
and juniper. These mites go through four to six
generations per year and populations can explode under
warm, dry conditions.
Spider mites feed by sucking on plant sap. Damage is more
common on inner branches and areas protected from
direct rain. Infested needles become mottled and appear
yellowish to gray in color. Once damaged, needles will not
recover even after the mites are gone. Under heavy
infestations needles can brown or fall prematurely.
Conifers hold needles for up to four years so damage is
sometimes found that represents an old infestation.
Because other conifer disorders have similar symptoms,
the presence of mites or mite eggs is used for diagnosing
the problem. Plants should only be treated if mites are
active or if large numbers of overwintering eggs are found
on shoots. 18
Source: UW
Extension

19. Acari - Spruce Spider Mite
Mouthparts: Paired, piercing - Spruce spider mites feed
by poking their sharp, scissor-like mouthparts into a
needle, injecting saliva, and then sucking out the
predigested "soup."
Metamorphosis: None
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Source: NC State Extension, NM State Extension

20. Gastropoda- Slugs
Slugs damage plants by chewing large,
irregular holes in leaves, stems,
flowers or fruits. Most feeding occurs
at night or during dark, cloudy days.
A shiny trail of mucus (slime) may be
associated with the damage.
Vegetables and fruit in direct contact
with the soil are attacked more
frequently than those off the ground.
In Wisconsin, tomatoes are often
damaged just as they ripen.
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Source: UW Extension

21. Gastropoda- Slugs
Mouthparts: Snails and slugs eat with a
jaw and a flexible band of thousands of
microscopic teeth, called a radula. The
radula scrapes up, or rasps, food particles
and the jaw cuts off larger pieces of food,
like a leaf, to be rasped by the radula.
Metamorphosis: Simple
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Source: LA Natural History Museum (very cool)

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The End.