Beneficial Organisms

Beneficial

Organismos beneficiosos

Mites

Ácaros

Spiders

Arañas

Biological Control

Control biológico

Insects

Insectos

Lawn and Garden Care: Pest Management

Lawn and Garden Pest Management

Landscape Pest Management in Florida

Citrus Insects and Mites

Citrus Soft-Bodied Pests

Mites are arachnids that are found in almost every environment with more than 55,000 described species worldwide. Some mites are classified as pests, while others are beneficial. Those who study mites are known as acarologists. Fewer than 100 scientists in the United States specialize in mites of agricultural importance. “This is a problem. Mites are [&#8230;]

<figure id="attachment_43429" aria-describedby="caption-attachment-43429" style="width: 693px" class="wp-caption alignright"><img decoding="async" fetchpriority="high" class=" wp-image-43429" src="https://blogs.ifas.ufl.edu/news/files/2024/03/Twospotted_Mite_UF_IFAS_Photography-300x201.jpeg" alt="" width="693" height="464" /><figcaption id="caption-attachment-43429" class="wp-caption-text">The two-spotted mite species is a major pest on more than 200 species of plants including fruit, ornamental and vegetable crops. Courtesy UF IFAS Photography.</figcaption></figure>
Mites are arachnids that are found in almost every environment with more than 55,000 described species worldwide. Some mites are classified as pests, while others are beneficial.
Those who study mites are known as acarologists.
Fewer than 100 scientists in the United States specialize in mites of agricultural importance.
“This is a problem. Mites are multiplying and emerging in agriculture as a species of economic importance worldwide due to their threat to a variety of commodities and crops,” said <a href="https://trec.ifas.ufl.edu/people/alexandra-revynthi/">Alexandra Revynthi</a>, an assistant professor of ornamental entomology and acarology at the <a href="https://trec.ifas.ufl.edu/">UF/IFAS Tropical Research and Education Center (TREC)</a>.
That is why she is working on growing the number of experts available to tackle pest mites. Back by popular demand, she will host the <a href="https://trec.ifas.ufl.edu/people/alexandra-revynthi/agricultural-acarology-workshop/workshop-overview/">Agriculture Acarology Workshop</a>, May 6-9, 9 a.m. to 5 p.m. at the 18905 SW 280 St., Homestead, Fla. Space is limited to 17 participants.
The workshop is designed for graduate students, Extension agents, government and state agents, biological control practitioners, local growers and grove managers from around the world.
By the end of the weeklong workshop, participants will be able to identify:
<ul>
<li>Major groups of pest and predatory mites in the lab as well as in the field.</li>
<li>Local pest mites and recommend management strategies.</li>
<li>Natural enemies of pest mites and implement them in an integrated pest management program (IPM).</li>
</ul>
Cost to attend is $300 for students and $700 for other participants. <a href="https://www.eventbrite.com/e/3rd-agricultural-acarology-workshop-tickets-815629348337?aff=oddtdtcreator">Registration is required</a>.
“Mites are diverse in so many ways when you consider their habitat, their behavior, their feeding habits, their body shape, size and color. We can find them everywhere including the oceans,” said Revynthi. “They can be beneficial, parasites of plants, animals, or other arthropods, and decomposers. They are very small, and this intimidates many researchers, but the damage they can cause is inversely proportional to their size.”
Acarology has made vital contributions to the sustainability of agriculture. Many biological control agents are mites. A critical example of sustainable mite management in Florida was the development of a postharvest treatment for the <a href="https://edis.ifas.ufl.edu/publication/IN1347">Lychee erinose mite</a> (LEM), an invasive pest that infests lychee trees. Once identified, a quarantine was established and growers were prohibited from selling the fruit outside of Lee County, the epicenter of the infestation.
<figure id="attachment_43433" aria-describedby="caption-attachment-43433" style="width: 557px" class="wp-caption alignleft"><img decoding="async" class=" wp-image-43433" src="https://blogs.ifas.ufl.edu/news/files/2024/03/Evaluating_infestations_of_the_red-palm-mite_UFIFAS_Photography-300x200.jpeg" alt="" width="557" height="371" /><figcaption id="caption-attachment-43433" class="wp-caption-text">Daniel Carrillo, associate professor, and Jorge Peña, emeritus professor, both of the UF/IFAS entomology and nematology department at TREC, evaluate infestations of the red palm mite.</figcaption></figure>
To solve this problem, <a href="https://bioone.org/journals/florida-entomologist/volume-103/issue-2/024.103.0224/Post-Harvest-Paraffinic-Oil-Dips-to-Disinfest-Lychee-Fruit-of/10.1653/024.103.0224.full">Revynthi together with researchers from UF/IFAS and U.S. Department of Agriculture</a> tested dipping lychee fruit in an oil solution for 60 seconds after picking them. The treatment killed the mites and other bugs without impacting the fruit quality allowing growers to disinfect the fruit and safely sell it outside the state. The treatment was approved by the Florida Department of Agriculture and Consumer Services Division of Plant Industry.
“In my opinion mites are the best arthropods to use to conduct fundamental research,” said Revynthi. “Their ability to reproduce fast and in large numbers makes them the perfect arthropod study system to answer questions related to evolutionary biology and population dynamics.”
While the workshop is most beneficial for students who are starting their studies on mites or on systems that involve mites, it is also a critical tool for Extension and regulatory agents who see samples every day.
“Students learn how to maintain mite colonies, how to conduct experiments and bioassays, how to collect, extract, mount and identify the mites at least to the family level,” she said. “We provide information on the four main pest groups of mites and their predators. We try to bring experts from all over the world to share their knowledge and passion for this area of expertise.”
Growers and grove managers will benefit from learning how to scout and recognize mite pests based on the symptoms as well as how to approach an infestation. The workshop provides information about the management and the biocontrol agents that are available in the market.
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By Lourdes Mederos, <a href="mailto:rodriguezl@ufl.edu">rodriguezl@ufl.edu</a>
ABOUT UF/IFAS 
The mission of the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) is to develop knowledge relevant to agricultural, human and natural resources and to make that knowledge available to sustain and enhance the quality of human life. With more than a dozen research facilities, 67 county Extension offices, and award-winning students and faculty in the UF College of Agricultural and Life Sciences, UF/IFAS brings science-based solutions to the state’s agricultural and natural resources industries, and all Florida residents. 
<a href="http://www.ifas.ufl.edu">ifas.ufl.edu</a>  |  <a href="https://twitter.com/UF_IFAS">@UF_IFAS</a>
 
WHY FOOD IS OUR MIDDLE NAME 
Feeding a hungry world takes effort. Nearly everything we do comes back to food: from growing it and getting it to consumers, to conserving natural resources and supporting agricultural efforts. Explore all the reasons why at <a href="https://ifas.ufl.edu/food/">ifas.ufl.edu/food</a> or follow <a href="https://twitter.com/search?q=%23FoodIsOurMiddleName&amp;src=typed_query">#FoodIsOurMiddleName</a>.
&nbsp;
&nbsp;

The two-spotted mite species is a major pest on more than 200 species of plants including fruit, ornamental and vegetable crops. Courtesy UF IFAS Photography.
Mites are arachnids that are found in almost every environment with more than 55,000 described species worldwide. Some mites are classified as pests, while others are beneficial.
Those who study mites are known as acarologists.
Fewer than 100 scientists in the United States specialize in mites of agricultural importance.
“This is a problem. Mites are multiplying and emerging in agriculture as a species of economic importance worldwide due to their threat to a variety of commodities and crops,” said Alexandra Revynthi, an assistant professor of ornamental entomology and acarology at the UF/IFAS Tropical Research and Education Center (TREC).
That is why she is working on growing the number of experts available to tackle pest mites. Back by popular demand, she will host the Agriculture Acarology Workshop, May 6-9, 9 a.m. to 5 p.m. at the 18905 SW 280 St., Homestead, Fla. Space is limited to 17 participants.
The workshop is designed for graduate students, Extension agents, government and state agents, biological control practitioners, local growers and grove managers from around the world.
By the end of the weeklong workshop, participants will be able to identify:
Major groups of pest and predatory mites in the lab as well as in the field.
Local pest mites and recommend management strategies.
Natural enemies of pest mites and implement them in an integrated pest management program (IPM).
Cost to attend is $300 for students and $700 for other participants. Registration is required.
“Mites are diverse in so many ways when you consider their habitat, their behavior, their feeding habits, their body shape, size and color. We can find them everywhere including the oceans,” said Revynthi. “They can be beneficial, parasites of plants, animals, or other arthropods, and decomposers. They are very small, and this intimidates many researchers, but the damage they can cause is inversely proportional to their size.”
Acarology has made vital contributions to the sustainability of agriculture. Many biological control agents are mites. A critical example of sustainable mite management in Florida was the development of a postharvest treatment for the Lychee erinose mite (LEM), an invasive pest that infests lychee trees. Once identified, a quarantine was established and growers were prohibited from selling the fruit outside of Lee County, the epicenter of the infestation.
Daniel Carrillo, associate professor, and Jorge Peña, emeritus professor, both of the UF/IFAS entomology and nematology department at TREC, evaluate infestations of the red palm mite.
To solve this problem, Revynthi together with researchers from UF/IFAS and U.S. Department of Agriculture tested dipping lychee fruit in an oil solution for 60 seconds after picking them. The treatment killed the mites and other bugs without impacting the fruit quality allowing growers to disinfect the fruit and safely sell it outside the state. The treatment was approved by the Florida Department of Agriculture and Consumer Services Division of Plant Industry.
“In my opinion mites are the best arthropods to use to conduct fundamental research,” said Revynthi. “Their ability to reproduce fast and in large numbers makes them the perfect arthropod study system to answer questions related to evolutionary biology and population dynamics.”
While the workshop is most beneficial for students who are starting their studies on mites or on systems that involve mites, it is also a critical tool for Extension and regulatory agents who see samples every day.
“Students learn how to maintain mite colonies, how to conduct experiments and bioassays, how to collect, extract, mount and identify the mites at least to the family level,” she said. “We provide information on the four main pest groups of mites and their predators. We try to bring experts from all over the world to share their knowledge and passion for this area of expertise.”
Growers and grove managers will benefit from learning how to scout and recognize mite pests based on the symptoms as well as how to approach an infestation. The workshop provides information about the management and the biocontrol agents that are available in the market.
 
 
 
###
By Lourdes Mederos, rodriguezl@ufl.edu
ABOUT UF/IFAS
The mission of the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) is to develop knowledge relevant to agricultural, human and natural resources and to make that knowledge available to sustain and enhance the quality of human life. With more than a dozen research facilities, 67 county Extension offices, and award-winning students and faculty in the UF College of Agricultural and Life Sciences, UF/IFAS brings science-based solutions to the state’s agricultural and natural resources industries, and all Florida residents. 
ifas.ufl.edu  |  @UF_IFAS
 
WHY FOOD IS OUR MIDDLE NAME
Feeding a hungry world takes effort. Nearly everything we do comes back to food: from growing it and getting it to consumers, to conserving natural resources and supporting agricultural efforts. Explore all the reasons why at ifas.ufl.edu/food or follow #FoodIsOurMiddleName.

Mites are arachnids that are found in almost every environment with more than 55,000 described species worldwide. Some mites are classified as pests, while others are beneficial. Those who study mites are known as acarologists. Fewer than 100 scientists in the United States specialize in mites of agricultural importance. “This is a problem. Mites are […]

Unlocking the secrets of mites: Agricultural acarology workshop aims to increase expertise in this emerging science

Recap of January 2024 First Friday with Florida First Detector For our first webinar of 2024, we focused on mites! As a group, mites are incredibly diverse. There are mites pretty much everywhere. You can find them on plants, animals, people, stored products, soil, water and more! Some mites feed on animals and humans. Some [&#8230;]

<h2>Recap of January 2024 First Friday with Florida First Detector</h2>
For our first webinar of 2024, we focused on mites! As a group, mites are incredibly diverse. There are mites pretty much everywhere. You can find them on plants, animals, people, stored products, soil, water and more! Some mites feed on animals and humans. Some work as decomposers to break down things in the environment. There are even some mites that feed on plants and they can be a pest for us. Other mites are actually predatory and used for biological control of mites, insects and other pests.
As far as plant pests go, the three most economically important families are Tetranychidae (spider mites), Eriophyidae (gall mites), and Tenuipalpidae (false spider mites). Like all mites, plant feeding mites can be distinguished from plant feeding insects by looking at their basic anatomy. Mites will have two body regions with a gnathosoma and an idiosoma. Other arachnids, like spiders and scorpions, lack the gnathosoma. Mites also have four pairs of legs in the adult stage. Insects have three body regions and three pairs of legs. Mites are often very small and may require magnification to see these distinguishing features.
One of the most infamous mites in agriculture and horticulture is the twospotted spider mite, Tetranychus urticae. This species is native to Eurasia but is currently a pest in many temperate and subtropical regions of the world including Florida. It feeds on over 200 plants including edible crops and ornamentals. We also discussed the bermudagrass mite (Eriophyes cynodoniensis), the red palm mite (Raoiella indica), and the lychee erinose mite (Aceria litchii). These three species are invasive species that are currently causing problems on Florida&#8217;s plants.
We also discussed three species that are not known to be established in Florida including rose rosette virus mite, (Phyllocoptes fructiphilus), Japanese zelkova eriophyid mite (Aceria zelkoviana), and citrus brown mite, (Eutetranychus orientalis). For these species, we are monitoring to ensure they do not spread in Florida. Mites can be challenging to identify, even with magnification. If you are seeing unusual damage caused by mites, we suggest reaching out to your local county extension office for help in identification.
<h3>Resources on invasive plant feeding mites</h3>
<ul>
<li><a href="https://keys.lucidcentral.org/keys/v3/mites/Invasive_Mite_Identification/key/Whole_site/Home_whole_key.html">Invasive Mite ID Lucid Key</a></li>
<li><a href="https://www.fdacs.gov/Agriculture-Industry/Pests-and-Diseases/Plant-Pests-and-Diseases/Red-Palm-Mite">FDACS Red Palm Mite Resources</a></li>
<li><a href="https://edis.ifas.ufl.edu/publication/IN711">UF EDIS, Ask IFAS Red Palm Mite</a></li>
<li><a href="https://edis.ifas.ufl.edu/publication/IN307">UF EDIS, Ask IFAS Twospotted Spider Mite</a></li>
<li><a href="https://edis.ifas.ufl.edu/publication/CH179">UF EDIS, Ask IFAS A Guide to Citrus Mite ID</a></li>
<li><a href="https://pesttracker.org/pest?code=ILAVCEA#:~:text=Citrus%20brown%20mite%20(Eutetranychus%20orientalis,detected%20in%20Hawaii%20in%201991.">Pest Tracker Citrus Brown Mite</a></li>
<li><a href="https://trec.ifas.ufl.edu/Lychee-Erinose-Mite/">UF Tropical Research and Education Center Lychee Erinose Mite Resources</a></li>
<li><a href="https://www.fdacs.gov/Agriculture-Industry/Pests-and-Diseases/Plant-Pests-and-Diseases/Lychee-Erinose-Mite">FDACS Lychee Erinose Mite Resources </a></li>
<li><a href="https://www.fdacs.gov/content/download/66453/file/Pest%20Alert%20-%20Aceria%20zelkoviana,%20Japanese%20zelkova%20eriophyid%20mite.pdf">FDACS Pest Alert Japanese Zelkova Eriophyid Mite</a></li>
<li><a href="https://www.fdacs.gov/content/download/84595/file/Pest-Alert-Rose%20rosette-virus-mite02121.pdf">FDACS Pest Alert Rose Rosette Virus Mite</a></li>
</ul>
<h2>Want to watch the recording?</h2>
<iframe title="January 2024 First Friday with Florida First Detector: Invasive Plant Feeding Mites" width="500" height="375" src="https://www.youtube.com/embed/FAM_hR_eb8c?feature=oembed" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen></iframe>
<h2>What is the upcoming schedule?</h2>
We are meeting online via Zoom from 12:00PM-1:00PM on the First Friday of every month from Sept 2022-Aug 2024. Please visit <a href="https://blogs.ifas.ufl.edu/seminoleco/2023/07/17/first-fridays-with-ffd-24/">this blog</a> for registration information and the upcoming schedule for Sept 2023-2024.
<h2>Questions?</h2>
Contact Dr. Morgan Pinkerton, <a href="mailto:morgan0402@ufl.edu">morgan0402@ufl.edu</a>
Or
Visit the <a href="http://www.flfirstdetector.com/">Florida First Detector Website</a>

Recap of January 2024 First Friday with Florida First Detector
For our first webinar of 2024, we focused on mites! As a group, mites are incredibly diverse. There are mites pretty much everywhere. You can find them on plants, animals, people, stored products, soil, water and more! Some mites feed on animals and humans. Some work as decomposers to break down things in the environment. There are even some mites that feed on plants and they can be a pest for us. Other mites are actually predatory and used for biological control of mites, insects and other pests.
As far as plant pests go, the three most economically important families are Tetranychidae (spider mites), Eriophyidae (gall mites), and Tenuipalpidae (false spider mites). Like all mites, plant feeding mites can be distinguished from plant feeding insects by looking at their basic anatomy. Mites will have two body regions with a gnathosoma and an idiosoma. Other arachnids, like spiders and scorpions, lack the gnathosoma. Mites also have four pairs of legs in the adult stage. Insects have three body regions and three pairs of legs. Mites are often very small and may require magnification to see these distinguishing features.
One of the most infamous mites in agriculture and horticulture is the twospotted spider mite, Tetranychus urticae. This species is native to Eurasia but is currently a pest in many temperate and subtropical regions of the world including Florida. It feeds on over 200 plants including edible crops and ornamentals. We also discussed the bermudagrass mite (Eriophyes cynodoniensis), the red palm mite (Raoiella indica), and the lychee erinose mite (Aceria litchii). These three species are invasive species that are currently causing problems on Florida’s plants.
We also discussed three species that are not known to be established in Florida including rose rosette virus mite, (Phyllocoptes fructiphilus), Japanese zelkova eriophyid mite (Aceria zelkoviana), and citrus brown mite, (Eutetranychus orientalis). For these species, we are monitoring to ensure they do not spread in Florida. Mites can be challenging to identify, even with magnification. If you are seeing unusual damage caused by mites, we suggest reaching out to your local county extension office for help in identification.
Resources on invasive plant feeding mites
Invasive Mite ID Lucid Key
FDACS Red Palm Mite Resources
UF EDIS, Ask IFAS Red Palm Mite
UF EDIS, Ask IFAS Twospotted Spider Mite
UF EDIS, Ask IFAS A Guide to Citrus Mite ID
Pest Tracker Citrus Brown Mite
UF Tropical Research and Education Center Lychee Erinose Mite Resources
FDACS Lychee Erinose Mite Resources 
FDACS Pest Alert Japanese Zelkova Eriophyid Mite
FDACS Pest Alert Rose Rosette Virus Mite
Want to watch the recording?

What is the upcoming schedule?
We are meeting online via Zoom from 12:00PM-1:00PM on the First Friday of every month from Sept 2022-Aug 2024. Please visit this blog for registration information and the upcoming schedule for Sept 2023-2024.
Questions?
Contact Dr. Morgan Pinkerton, morgan0402@ufl.edu
Or
Visit the Florida First Detector Website

Recap of January 2024 First Friday with Florida First Detector For our first webinar of 2024, we focused on mites! As a group, mites are incredibly diverse. There are mites pretty much everywhere. You can find them on plants, animals, people, stored products, soil, water and more! Some mites feed on animals and humans. Some […]

January 2024 First Friday with Florida First Detector

When does a blight on a plant look like a disease, but is not?  A Mexican petunia with a disease-like condition that is actually caused by microscopic mites is the answer!  Many gardeners who have Mexican petunias experience this plague from time to time.  It looks just like a fungus but is actually caused by [&#8230;]

<figure id="attachment_7775" aria-describedby="caption-attachment-7775" style="width: 400px" class="wp-caption alignright"><img decoding="async" loading="lazy" class=" wp-image-7775" src="https://blogs.ifas.ufl.edu/charlotteco/files/2023/05/20230425_152256-300x286.jpg" alt="white hair-like substance on a plant stem" width="400" height="382" /><figcaption id="caption-attachment-7775" class="wp-caption-text">Felt-like damage on a Mexican Petunia</figcaption></figure>
When does a blight on a plant look like a disease, but is not?  A Mexican petunia with a disease-like condition that is actually caused by microscopic mites is the answer!  Many gardeners who have Mexican petunias experience this plague from time to time.  It looks just like a fungus but is actually caused by a minute arachnid called an eriophyid mite.
Now, I am not promoting Ruellia simplex as they have an invasive nature and according to the Florida Exotic Pest Plant Council or FLEPPC, it is a “CATEGORY I Invasive exotics that is altering native plant communities by displacing native species, changing community structures or ecological functions, or hybridizing with natives. This definition does not rely on the economic severity or geographic range of the problem, but on the documented ecological damage caused.” Also, UF/IFAS Assessment of Non-Native Plants in Florida’s Natural Areas indicates that Ruellia simplex is not recommended as it is invasive.  However, the sterile cultivars ‘Purple Showers’, ‘Mayan White &#x2122;’, ‘Mayan Purple &#x2122;’ and ‘Mayan Pink &#x2122;’ can be used with caution so that they do not escape.
So, with that information unpacked, let’s get back to our main topic – fuzzy white distorted growth on Mexican Petunias.  As mentioned, this damage is caused by an eriophyid mite.  The mites feed on the leaves causing
felt-like galls to develop giving the appearance of a powdery or downy mildew infection.  This does not kill the plant but does reduce its ornamental appeal.
Least-toxic management of the eriophyid mite involves the use of horticultural oil – applied as per label directions and not in the heat of the day as it will burn the leaves &#8211; every five to seven days for a total of three applications.   This will take care of this battle, but mites may return, so monitor frequently to suppress any small infestations.
Although microscopic, there should be no mystery about eriophyid mites as they are the real cause of the wooly leaves on Mexican petunias – easily managed with a least-toxic approach.  For more information on all types of plant pests and disorders, or to ask a question, you can also call the Master Gardener Volunteer Helpdesk on Mondays, Wednesdays, and Fridays from 1 to 4 pm at 764-4340 for gardening help and insight into their role as an Extension volunteer.  Ralph E. Mitchell is the Director/Horticulture Agent for UF/IFAS Extension &#8211; Charlotte County. He can be reached at 941-764-4344 or <a href="mailto:ralph.mitchell@charlottecountyfl.gov">ralph.mitchell@charlottecountyfl.gov</a>  .  Connect with us on social media. Like us on Facebook <a href="https://www.facebook.com/CharlotteCountyExtension">@CharlotteCountyExtension</a> and follow us on Instagram <a href="https://www.instagram.com/ifascharco/">@ifascharco</a>.
Resources: 
Caldwell, D. (2009) White stuff on Mexican petunia&#8212;.  The University of Florida Extension Service, IFAS – Collier County. 
2019 Florida Exotic Pest Plant Council &#8211;  <a href="https://bugwoodcloud.org/CDN/fleppc/plantlists/2019/2019_Plant_List_ABSOLUTE_FINAL.pdf">https://bugwoodcloud.org/CDN/fleppc/plantlists/2019/2019_Plant_List_ABSOLUTE_FINAL.pdf</a> . 
The UF/IFAS Assessment of Non-native Plants in Florida’s Natural Areas.  (2023) The University of Florida Extension Service, IFAS. 
Wilson, S. B., Burkhead, A., Adams C.  R., and Freyre, R. (2020) NATURAL AREA WEEDS: MEXICAN PETUNIA (RUELLIA SIMPLEX). The University of Florida Extension Service, IFAS. 
Borden, M. (2023) Eriophyid Mites: What They Are and How to Control Them in the Home Garden.  Fine Gardening. <a href="https://www.finegardening.com/article/eriophyid-mites-what-they-are-and-how-to-control-them-in-the-home-garden">https://www.finegardening.com/article/eriophyid-mites-what-they-are-and-how-to-control-them-in-the-home-garden</a>

Felt-like damage on a Mexican Petunia
When does a blight on a plant look like a disease, but is not?  A Mexican petunia with a disease-like condition that is actually caused by microscopic mites is the answer!  Many gardeners who have Mexican petunias experience this plague from time to time.  It looks just like a fungus but is actually caused by a minute arachnid called an eriophyid mite.
Now, I am not promoting Ruellia simplex as they have an invasive nature and according to the Florida Exotic Pest Plant Council or FLEPPC, it is a “CATEGORY I Invasive exotics that is altering native plant communities by displacing native species, changing community structures or ecological functions, or hybridizing with natives. This definition does not rely on the economic severity or geographic range of the problem, but on the documented ecological damage caused.” Also, UF/IFAS Assessment of Non-Native Plants in Florida’s Natural Areas indicates that Ruellia simplex is not recommended as it is invasive.  However, the sterile cultivars ‘Purple Showers’, ‘Mayan White ™’, ‘Mayan Purple ™’ and ‘Mayan Pink ™’ can be used with caution so that they do not escape.
So, with that information unpacked, let’s get back to our main topic – fuzzy white distorted growth on Mexican Petunias.  As mentioned, this damage is caused by an eriophyid mite.  The mites feed on the leaves causing
felt-like galls to develop giving the appearance of a powdery or downy mildew infection.  This does not kill the plant but does reduce its ornamental appeal.
Least-toxic management of the eriophyid mite involves the use of horticultural oil – applied as per label directions and not in the heat of the day as it will burn the leaves – every five to seven days for a total of three applications.   This will take care of this battle, but mites may return, so monitor frequently to suppress any small infestations.
Although microscopic, there should be no mystery about eriophyid mites as they are the real cause of the wooly leaves on Mexican petunias – easily managed with a least-toxic approach.  For more information on all types of plant pests and disorders, or to ask a question, you can also call the Master Gardener Volunteer Helpdesk on Mondays, Wednesdays, and Fridays from 1 to 4 pm at 764-4340 for gardening help and insight into their role as an Extension volunteer.  Ralph E. Mitchell is the Director/Horticulture Agent for UF/IFAS Extension – Charlotte County. He can be reached at 941-764-4344 or ralph.mitchell@charlottecountyfl.gov  .  Connect with us on social media. Like us on Facebook @CharlotteCountyExtension and follow us on Instagram @ifascharco.
Resources:
https://bugwoodcloud.org/CDN/fleppc/plantlists/2019/2019_Plant_List_ABSOLUTE_FINAL.pdf .
https://www.finegardening.com/article/eriophyid-mites-what-they-are-and-how-to-control-them-in-the-home-garden

When does a blight on a plant look like a disease, but is not?  A Mexican petunia with a disease-like condition that is actually caused by microscopic mites is the answer!  Many gardeners who have Mexican petunias experience this plague from time to time.  It looks just like a fungus but is actually caused by […]

Mites are not a disease

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Unlocking the secrets of mites: Agricultural acarology workshop aims to increase expertise in this emerging science

January 2024 First Friday with Florida First Detector

Mites are not a disease

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