What Causes Citrus Flyspeck – Treating Symptoms Of Flyspeck Fungus

By: Mary Ellen Ellis

Growing citrus trees can be a great joy, providing a beautiful landscaping element, shade, screening, and of course, delicious, home-grown fruit. And there is nothing worse than going to harvest your oranges or grapefruits and finding they have been damaged by the flyspeck fungus.

Spotting Flyspeck on Citrus

Citrus flyspeck is a disease that may affect any type of citrus tree, but it is confined to the fruit. Look for small black dots, or specks the size of a small fly, on the rind of citrus fruits. The specks are typically seen near the oil glands, and they prevent that part of the fruit from turning color.

The area of the rind with the specks generally stays green or sometimes yellow, depending on the type of fruit. There may also be a sooty covering on the rind, but this sometimes disappears, leaving just the flyspecks.

What Causes Citrus Flyspeck?

Citrus flyspeck is a disease caused by a fungus called Leptothyrium pomi. There may be other species of fungus that cause the infection as well. The sooty covering and the small black spots are fungus strands, not spores. How the fungus spreads is not fully understood, but it is likely that pieces of the sooty-like material break off and are blown from one citrus tree to another.

Treating Citrus Flyspeck

The good news about citrus flyspeck is that it doesn’t actually damage the internal quality of the fruit. You can still eat or juice the fruits, even with the specks present. The fruits don’t look very nice, though, and if you want to treat your tree, you can try an antifungal spray recommended by your local nursery or agricultural extension. You can also wash off the fungus after picking the fruit.

How to prevent citrus flyspeck is also not well understood, but with most types of fungus, it’s important to avoid getting the leaves or fruit wet and provide plenty of space for airflow. Flyspeck may ruin the appearance of your citrus tree, but it doesn’t have to ruin the enjoyment of your lemons, limes, oranges, and other citrus fruit.

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Flyspeck On Citrus Fruits: Learn How To Prevent Citrus Flyspeck Disease - garden

Flowable Liquid Copper Fungicide with Low-Load Copper Soap

Fixed copper has long been coveted as an excellent broad spectrum fungicide and bactericide. Cueva brings this age-old ingredient up to date with this patented flowable liquid formulation. Organic Cueva combines a soluble copper fertilizer with a fatty acid to create a true soap. The fatty acid basis of this formula works two ways: to help the active ingredient of copper get into the fungal or bacterial cells and by helping spread the material across plant surfaces. Once the copper itself is in the pathogenic cells, it will denature the cells and cause fatal cell leakage. As Cueva moves across the plants and into the cells, it helps protect the plants from potential or further damage by creating a hostile environment for infection or re-infection.

Key Features:

  • For this product to achieve optimal performance, it should be on the leaf or fruit before an infection occurs.
  • Controls diseases that go dormant and overwinter, like Peach Leaf Curl.
  • 4-hour REI (Restricted Entry Interval) and 0-day PHI (Pre-Harvest Interval)
  • Approved for use on Hemp in the state of Colorado.
  • OMRI listed under Crop Pest, Weed and Disease Control and NOP compliant.
Suggested Use: Intended for commercial use only to be applied to control fungal and bacterial diseases on a broad range of crops.

This Product Controls These Pests or Diseases: Alternaria Blight, Anthracnose, Ascochyta Leaf and Pod Spot, Bacterial Blast, Bacterial Cankers, Bacterial Speck, Bacterial Spots/Rots, Black Knot (on plums), Black Pitting, Black Pod, Blights, Blue Mold, Blotch, Botryosphaeria Panicle, Botrytis/Grey Mold, Brown Mold, Brown Rot, Citrus Canker, Coffee Berry Disease, Downy Mildew, Fire Blight, Flyspeck, Fruit Spot, Jacket Rot, Leaf Smut, Leaf Spots, Olive Knot, Pink Disease, Peach Leaf Curl, Phomopsis, Potato Brown Rot, Powdery Mildew, Pseudomonas, Rhizoctonia, Rose Bloom, Rusts, Scab, Sigatoka (black and yellow), Sooty Mold, Stewart's Wilt and White Mold.

Tank Mixing Instructions:

  • Pour into spray tank at least half filled with water using adequate agitation.
  • When mixed with other products proven or known to be compatible, wettable powders should be added first, followed in order by flowables (such as Cueva) and then emulsifiable concentrates.
  • Use caution and read all labels thoroughly when mixing with chelated or liquid fertilizers or other fungicides and insecticides. Please see manufacturer's label under the DOCS tab for a list of products that can be mixed with Cueva.

Chemigation Requirements:

  • Apply this product only through sprinkler systems, including center pivot, lateral move, end tow, side (wheel) roll, traveler, bug gun, solid set or hand move. Do not apply this product through any other type of irrigation system.
  • Crop injury, loss of effectiveness, or illegal pesticide residues in the crop can result from non-uniform distribution of treated water.
  • Please see manufacturer's label under the DOCS tab for more detailed Chemigation instructions.

Usage Notes: Most conventional liquid pesticide plant sprayers can be used to apply Cueva. A spreader may be used to improve the spreading on hard-to-wet plants. Do not apply when wind speed favors drift beyond the area intended. May cause some copper toxicity on some plant species.


  • Fruit and Nut Crops: Almonds, Avocados, Bananas/Plantains, Blueberries, Cacao, Caneberries (Blackberries, Raspberries), Citrus, Coffee, Cranberries, Currants, Filberts (WA & OR only), Gooseberries, Grapes, Guavas, Kiwi, Lychee, Macadamia, Mangos, Mamey Sapote, Olives, Papayas, Passion Fruit, Pecans, Pome Fruits, Starfruit, Stone Fruits, Strawberries, Sugar Apple (Annona)and Walnuts.
  • Herbs and Field-Grown Vegetables: Alfalfa, Artichokes, Basil, Beans, Beets, Carrots, Celery and Celeriac, Chicory, Chives, Cereal Grains (Wheat, Oats, Barley), Coriander, Corn, Crucifer Crops (Broccoli, Brussel Sprouts, Cauliflower, Cabbage, Chinese Cabbage, Collard Greens, Endive, Kale, Kohlrabi, Mustard Greens, Turnip Greens), Cururbits (Canataloupe, Cucumbers, Melons, Squash, Pumpkin, Zucchini, Watermelon), Dill, Eggplant, Garlic, Ginseng, Hops, Lavender, Leek, Lettuce, Mint, Okra, Onions, Parsley, Peanuts, Peppers, Potatoes, Rosemary, Shallots, Soybeans (not registered for use on soybeans in CA), Tomatoes, Tobacco and Watercress.

Storage: Do not contaminate water, food or feed by storage or disposal. Store in a secure place, away from open fire or flame. Keep container closed and reseal after use. Product may be damaged by freezing. Do not store product below 39.2°F (4°C). If spilled, use absorbent material and dispose of in an approved manner.

Warning & Toxicities: KEEP OUT OF REACH OF CHILDREN. Hazards to humans and domestic animals. Harmful if swallowed or absorbed through the skin. Avoid contact with skin, eyes or clothing. Wash hands thoroughly with soap and water after handling and before eating, drinking, chewing gum, using tobacco or using the toilet. Remove and wash contaminated clothing before reuse.

Environmental Hazards: This product is toxic to fish and aquatic organisms and may contaminate water through runoff. Do not apply directly to water, or to areas where surface water is present or to intertidal areas below the mean high water mark. Do not contaminate water by disposal of equipment washwaters or rinsate. This product may contaminate water through runoff. Poorly draining soils with shallow water tables are more prone to produce runoff that contains this product. Drift and runoff may be hazardous to aquatic organisms in water adjacent to treated areas.

Active Ingredients/Guaranteed Analysis:

10%. Copper Octanoate (Copper Soap)
90%. Other Ingredients

Metallic copper equivalent – 1.8% (0.16 lbs./gallon)

OMRI listed under Crop Pest, Weed and Disease Control

Gymnosporangium juniperi-virginianae

Rusts are fungi that will not kill their hosts, although they sure make them suffer. There is even a term for pathogens that require living hosts: biotrophs (in contrast to necrotrophs, pathogens that kill their host and live off the dead tissue).

Think Gloria Gaynor – your plants will survive! However, repeated infections of this pathogen can seriously weaken and destroy the health of susceptible plants. They will also lose any ornamental value.

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Read on to learn how to identify and control cedar apple rust in your garden or home orchard.

Features and Specs

Active Ingredient Pyraclostrobin 3.06%, boscalid 5.62%, lambda-Cyhalothrin 0.5%
Target pests Insects: Aphids, Japanese Beetles, Leafhoppers and others
Fungicide: Powdery Mildew, Apple Scab, Flyspeck and others
* See Label for complete list
For use in Flowers, Fruits, Nuts, Shrubs & Ornamental Trees
* See Label for complete list
Application Attach the applicator to the nozzle of the hose
Apply thoroughly as a foliar cover spray to all plant surfaces where insects or disease are present
* See Label for application rates
Pet safe Yes, if used as directed on Label
Coverage Area 32 oz. Treats up to 24,000 square feet
Shipping Weight 2.45 lbs
Manufacturer Bonide (Mfg. Number: 2071)
UPC 037321020714
EPA Registration 4-488



  1. Using a clean sprayer, measure and mix 2 fluid ounces per gallon of water.
  2. Do not use kitchen utensils such as measuring spoons and cups for food purposes after they have been used with pesticides.
  3. Spray as directed - complete coverage is important.
  4. Flush sprayer with clean water after use and apply rinsate to the treatment area.
  5. Carefully follow all label directions and any limitations of use, such as the amount of spray to apply of PHI (pre-harvest interval) for particular edible crops.


Ornamental Trees, Shrubs, and Flowers including (but not limited to):

Ageratum, Ash, Aster, Arborvitae, Arizona Cypress, Azaleas, Begonia, Birch, Boxwood, Boxelder, Camellias, Cherry (ornamental), Non-bearing Citrus, Chrysanthemum, Carnation, Coleus, Conifers, Douglas, Fir, Elm, English Ivy, Euonymus, Exacum, Weeping Fig, Fir, Gladioli, Gold Bells, Hawthorn, Holly, Honeysuckle, Hypoestes, Impatiens (may cause discoloration during flowering), Ivy, Juniper, Lilac, Locust, Maple, Marigold, Mimosa, Mock Orange, Nannyberry, Oak, Orchid, Palm, Pansy, Pea Shrub, Petunia, Philodendron, Pine, Ornamental Plum, Poinsettia, Poplar, Rhododendron, Roses, Snapdragon, Snowberry, Spruce, Taxus, Willow, Zinnia.

Pome Fruits:

Apple, Crabapple, Loquat, Mayhaw, Oriental Pear, Pear, Quince.

Stone Fruits:

Apricot, Cherry (sweet and tart), Nectarine, Peach, Plum, Plumcot, Prune.

Almond, Beech Nut, Brazil Nut, Butternut, Cashew, Chestnut, Chinquapin, Filbert (Hazelnut), Hickory, Macadamia Nut, Pecan, Walnut (Black and English).


American plum borers, Ants, Apple aphids, Apple maggots (adult), Armyworms, Aphids, Azalea caterpillars, Bagworms, Black cherry aphids, Black vine weevils (adult), Boxelder bugs, Budworms, Cankerworms, Chinch bugs, Cherry fruit flies spp. (adult), Cockroaches, Codling moths, Crickets, Cutworms, Eastern tent caterpillar, Elm leaf beetles, European sawflies, Fall webworms, Flea beetles, Filbertworms, Forest tent caterpillars, Green fruitworms, Gypsy moth larvae, Japanese beetles, June beetles (adults), Lace bugs, Leaf feeding caterpillars, Leaffooted bugs, Leafrollers spp., Leafhoppers spp., Leafminers (adult), Leaf skeletonizers, Lesser appleworms, Midges, Navel orangeworms, Oleander moth larvae, Omnivorous leafroller, Orange tortrixes, Oriental fruit moths, Peach twig borers, Peachtree borers spp., Pear sawflies, Pear psyllas spp., Periodical cicadas, Plant bugs spp., Plum curculios, Pillbugs, Pine sawflies, Pine shoot beetles, Pinetip moths, Root weevils, Rosy apple aphids, Rose chafers, Scale insects (crawlies), San Jose scales (fruit infestations only), Sawflies, Spirea aphids spp., Spiders, Spittlebugs, Striped beetles, Striped oakworms, Stink bugs spp., Tent caterpillars spp., Tentiform leafminers spp., Thrips spp., Tip moths, Tree borers spp., Tufted apple budworms, Tussock moth larvae, Walnut aphids, Walnut husk flies spp., (adult), and Webworms spp.


Alternaria blotch, Alternaria leaf spot, Anthracnose, Apple scab, Blossom blight, Bitter rot, Black rot, Brown rot, Botrytis rot, Crown and basal rot, Downy mildew, Frogeye leaf spot, Brooks spot, Flyspeck, Eastern filbert blight, Green fruit rot, Leaf spot, Leaf rust, Pear scab, Powdery mildew, Phytophthora blight, Ripe fruit rot, Rust, Scab, Scooty blotch, Shothole, and White rot.


Cedar apple rust, Nectarine, Peach, and Quince rust.

Watch the video: Citrus Leaf Curl Treatment: Citrus Leaf Curling Disease

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