Nothing ruins the joy of harvesting sweet, ripe strawberries quite like finding them riddled with tiny holes or tunnels The culprit? Strawberry sap beetles These tiny pests invade ripe and overripe strawberry fruits, marring their appearance and causing them to rot quickly.
Getting rid of sap beetles organically in your strawberry patch takes diligence, but it can be done. Here are effective methods to control strawberry sap beetles without chemicals.
Identifying Strawberry Sap Beetles
The first step is confirming strawberry sap beetles are the cause of damage, Look for
- Tiny dark beetles 1/8 inch long on ripe or damaged berries
- Small holes bored into sides of strawberry fruits
- Tunneled cavities with brown frass inside berries
- Shriveled, decaying berries with sap beetle larvae
Adult sap beetles are oval flattened dark brown to black insects. They have antennae with clubs on the ends. Ripe fruits damaged by other pests attract sap beetles to feed and lay eggs. Their larvae continue damaging the fruits from the inside out.
Why Control is Important
Strawberry sap beetle damage may seem minor at first. But left uncontrolled, sap beetle populations will multiply rapidly, ruining more and more of your strawberry harvest. Sap beetles also:
- Transmit fruit rotting fungal spores as they feed
- Cause berries to decay faster, spreading mold
- Ruin the appearance of berries, making them unsellable
- Allow larvae to tunnel deep, destroying whole fruits
Prompt sap beetle control keeps your strawberry harvest usable and prevents population explosions on your farm or in your garden.
Organic Ways to Get Rid of Strawberry Sap Beetles
These organic methods can help you control sap beetles without using chemical insecticides:
Remove Infested Berries
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Check ripe berries daily and discard any with sap beetle damage.
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Remove and destroy overripe or rotten fruits that attract sap beetles.
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Bury discarded fruits deep or seal in plastic bags to kill larvae inside.
Use Traps
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Set out traps with fermenting baits like wheat dough, vinegar, or ripe fruits.
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Place traps along edges of your strawberry patch to intercept beetles.
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Empty and refresh bait every 2-3 days to keep traps effective.
Keep Harvests Clean
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Pick berries daily as they ripen to prevent overripe fruits.
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Wash off berries immediately after picking to remove eggs or larvae.
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Keep ground debris-free to eliminate beetle hiding spots.
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Weed out wild berries, tree fruits, and alternate hosts near your patch.
Use Floating Row Covers
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Cover rows with lightweight fabric row covers to exclude beetles.
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Secure edges with soil or rocks to keep covers in place.
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Remove covers when berries start to ripen to allow pollination.
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Replace covers after daily harvests to exclude more beetles.
Apply Kaolin Clay
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Spray fruits with kaolin clay coats which deter sap beetles from feeding.
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Reapply after rainfalls to maintain protective barriers.
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Always follow label directions when applying to edible crops.
When to Use Pesticides for Sap Beetles
While organic methods are ideal, sometimes pesticides are needed to quickly reduce high strawberry sap beetle populations. Consider chemical control if:
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Traps and sanitation fail to protect ripening fruits.
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Beetle damage escalates to more than 10% of your crop.
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Harvests are nearing their peak with continued sap beetle issues.
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You cannot remove infested fruits fast enough to stay ahead of beetles.
If pesticide sprays are needed:
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Treat crops at first signs of sap beetle damage. Do not wait until fruits are ripe.
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Select targeted, low toxicity pesticides labeled for strawberries.
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Follow all label directions for dosage, timing, and pre-harvest intervals.
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Combine sprays with traps, row covers, and Good Agricultural Practices.
Preventing Strawberry Sap Beetles
Once you get sap beetles under control, focus on prevention to avoid recurrent issues:
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Use insect exclusion fabric row covers early in the season.
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Eliminate weeds, debris, and alternate beetle hosts around your strawberry patch.
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Apply kaolin clay coatings preventively before fruits start ripening.
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Maintain a rigorous harvest schedule, removing all ripe fruits daily.
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Scout for the first signs of sap beetle damage and act quickly.
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Rotate strawberry planting sites each year to disrupt pest cycles.
With good sanitation and a mix of organic controls, you can keep strawberry sap beetles in check and enjoy bountiful, damage-free berry harvests.
Related Websites and Resources
Blackmer, J. L. and P. L. Phelan. 1995. Ecological analyses of Nitidulidae: seasonal occurrence, host choice and habitat preference. J. Appl. Entomol. 119:321–329.
Dowd, P. F. and C. M. Weber. 1991. A work-sharing method for feeding pinto beans to a corn sap beetle species called Carpophilus freemani Dobson (Coleoptera: Nitidulidae). J. Agric. Entomol. 8:149–153.
Dowd, P. F. , D. E. Moore, F. E. Vega, M. R. Mcguire, R. J. Barlet, T. C. Nelson, and D. A. Miller. 1995. Occurrence of a Mermithid nematode parasite of Carpophilus lugubris (Coleoptera: Nitidulidae) in Central Illinois. Environ. Entomol. 24:1245–1251.
Loughner, R. L. , G. M. Loeb, K. Demchak, and Sonia Schloemann. 2007. Studying how strawberry sap beetles (Coleoptera: Nitidulidae) use the areas around strawberry plants as food sources and places to spend the winter Environ. Entomol. 36:1059–1065.
Myers, L. 2001. Sap beetles in Florida. University of Florida, Department of Entomology and Nematology. Featured Creatures. EENY-256.
Peng, C. and R. N. Williams. 1990. Pre-oviposition period, egg production and mortality of six species of hibernating sap beetles (Coleoptera: Nitidulidae). J. Econ. Entomol. 23:453–457.
Potter, M. A. , J. F. Price, D. H. Habeck, D. J. Schuster, and E. McCord Jr. 2013. A survey of sap beetles (Coleoptera: Nitidulidae) in strawberry fields in west central Florida. Fla. Entomol. 96:1188–1189.
Potter, M. A. 1995. The Nitidulidae (Coleoptera) associated with strawberry in eastern Hillsborough county, Florida. Thesis. University of Florida, Department of Entomology and Nematology. 98 pp.
Price, J. F. and C. A. Nagle. 2013. Insecticidal control of adult Haptoncus luteolus as a component of a comprehensive sap beetle management plan in strawberries. Int. J. Fruit Sci. 13:227–233.
Williams, R. N. , D. S Fickle, and J. R. Galford. 1992. Biological studies of Brachyserphus abruptus [Hym. : Proctotrupidae], a nitidulid parasite. Entomophaga. 37:91–98.
Release Date:August 29, 2017
Reviewed At:January 5, 2022
- DOI: doi.org/10.32473/edis-hs234-2004
- Critical Issue: 1. Agricultural and Horticultural Enterprises
The use of trade names in this publication is solely for the purpose of providing specific information. The products listed are not backed by UF/IFAS’s guarantee or warranty, and references to them in this publication do not mean that we only approve of them. Other products with the same composition are also fine.
Use pesticides safely. Read and follow directions on the manufacturers label.
This document is HS993, one of a series of the Horticultural Sciences Department, UF/IFAS Extension. Original publication date October 2004. Revised July 2017. Visit the EDIS website at https://edis. ifas. ufl. edu for the lastest version of this publication.
Silvia I. Rondon, former adjunct research associate, Horticultural Sciences Department; James F. Price, retired associate professor, Entomology and Nematology Department, UF/IFAS Gulf Coast Research and Education Center; Daniel J. Cantliffe, emeritus distinguished professor, Horticultural Sciences Department; and Justin M. Renkema, assistant professor, Entomology and Nematology Department, UF/IFAS GCREC; UF/IFAS Extension, Gainesville, FL 32611.
Sap Beetles in Florida
There are more than 4,500 species of sap beetles, with about 165 species in North America. Twenty-one genera have been reported in Florida including Carpophilus, Stelidota, Glischrochilus, and Epuraea (Myers 2001). Species in these genera are typically the most problematic agricultural pests. In Florida strawberries, Potter et al. (2013) found 9 species in seven east Hillsborough County fields (Plant City, FL). Here is a list of the species that are most common: Lobiopa insularis, Carpophilus fumatus, Carpophilus humeralis, Carpophilus freeman, Stelidota geminata, Stelidota ferruginea, Carpophilus mutilates, and Colopterus insularis.
Approximately 94% of the sap beetles were the top three species: E. luteolus, L. insularis, and C. fumatus; however, consideration must be given to all species. Correct identification should be followed by preventive methods to control damage by sap beetles.
Sap beetle adults fly into strawberry fields from surrounding fields or wooded areas. In temperate areas, flights happen when beetles come back from winter and when temperatures rise above 16°C (67°F) and strawberries start to ripen (Blackmer and Phelan 1995; Loughner et al. 2007). In Florida, sap beetles are common later in the harvest season, from February to March, when the weather gets warmer and fields full of pretty but damaged strawberries start to pile up (Price and Nagle 2013).
Both adult and larval sap beetles attack and feed on fruits. Longevity of adults is approximately 2 to 2½ months. A few hours after mating, most species lay their eggs on or under damaged or thrown away fruit, but some lay their eggs in the ground. After hatching from eggs, larvae burrow up into berries, feeding on the flesh for approximately 1½ weeks. Larvae then fall to the ground, burrow into the soil, and pupate. Sap beetles can find food in many places, but most of the time they eat fungus that grows on ripe and overripe plant parts, fruits, and other plant parts that are breaking down or ripening (Peng and Williams 1990; Myers 2001).
Sap beetles do two kinds of damage: direct (by making holes or cavities for food) and indirect (by spreading microorganisms). Cavities also serve as egg-laying sites. Larvae inside strawberries usually go unnoticed until the fruit begins to decompose as a result of the damage. Because sap beetles like overripe strawberries, the most damage happens when pickers leave ripe and overripe strawberry plants in the field or throw away fruit in ditches or along weedy field edges (Figure 4).
Sap beetles don’t usually hurt the economy when strawberries are picked in the field and sold right away. But when overripe strawberries are picked to be processed, sap beetles may get into the fruit and make it unsellable. Considering the ecology of sap beetles, the following practices are recommended.
If possible, avoid planting strawberry next to wooded areas. For timing controls, it’s important to keep an eye on when sap beetles fly into fields next to wooded areas. To stop sap beetles from coming into your field, put down pitfall traps (plastic cups buried flush with the ground and partially filled with soapy water) or “trap buckets” (an about 1-gallon bucket partially filled with soapy water and containing an 8-ounce plastic cup with fermenting banana, strawberry, or other fruit or bread dough placed in the bucket).
Pick berries frequently, before they become overripe. Take out any damaged or overripe fruit from the fields, but don’t throw them away in weedy areas, especially when it’s hot. Another good way to cut down on the number of adults in the field might be to pick infected fruit and put it in the middle of the rows (Potter 1995). In between rows, fruits break down faster than sap beetles can finish their life cycles, which stops their cycles. Keep in mind that fermenting berries may attract sap beetles capable of migrating from long distances (Potter 1995). Similar sanitation practices should be done with other fruits and vegetables.
A nematode parasite of one sap beetle species has been documented (Dowd et al. 1995). A commercially-available beneficial nematode (Steinernema carpocapsae) (eg, Millenium, BASF Corp. ) is effective against soil-dwelling stages of other strawberry beetle pests and may help keep sap beetles away.
A small parasitic wasp called Bradyserphus abruptus has been raised from several species of sap beetle and 99% of the time, young sap beetle larvae were infected, which stopped the wasp adults from emerging (Williams et al. 1992).
Apply recommended insecticides when conditions justify. Assail (acetamiprid), Brigade (bifenthrin), Danitol (fenpropathrin), and Rimon (novaluron) are insecticides that can be used to get rid of sap beetles (Price and Nagle 2013). Rimon is an insect-growth regulator and is only effective against sap beetle larvae. One of the other products on this list that works against adult sap beetles can be mixed with Rimon in a tank.
Biopesticides that contain azadirachtin or neem oil (like Azatin, Neemix, and Trilogy) will kill larvae and pupae and keep larvae and adults from feeding. Fungi that are insecticides (like Mycotrol O, Naturalis, and PFR-97) can kill larvae after being used several times and when the humidity is high. Products containing pyrethrins may also be used.
Insecticide use is limited by frequent harvests and pre-harvest intervals indicated on labels for specific products. Application(s) should be made when sap beetle adults are first detected. Follow insecticide label instructions for best results.
Sap Beetles in the Home Garden
FAQ
How to get rid of strawberry beetles?
How to prevent sap beetles?
Are sap beetles harmful?
How to get rid of strawberry pests?
How do you get rid of strawberry sap beetles?
Spray plants with insecticidal soap. Strawberry sap beetles are small oval insects, less than 1/8 inch long. They are dark colored, sometimes with yellow or orange spots. The damage to strawberries is caused by adult insects.
What are strawberry sap beetles?
Strawberry sap beetles are common in pick-your-own operations where ripe and overripe berries may remain in the field, which attract the beetle. Remove damaged, diseased, and overripe fruit from the patch at regular intervals to assist in reducing populations.
How do you get rid of beetles in a strawberry bed?
Place a bucket or other steep-sided container several feet away from the strawberry bed. Fill it with a few inches of stale beer; a mixture of water, molasses, and yeast; vinegar; or a mixture of water, a drop of liquid dish soap, and a few pieces of any overripe fruit. The beetles will crawl in after the bait and drown.
What attracts sap beetles?
Sap beetles are drawn to fruit that is over-ripe. Clean up fallen fruit from the ground, as decaying berries will attract sap beetles. Bait sap beetles by placing containers of stale beer or other overripe fruit, such as banana or melon, in a location well away from the strawberry patch.
How do you trap sap beetles?
The theory of trapping sap beetles is to place traps outside the garden or patch. Any container of fermenting plant juices will attract sap beetles. No special design is needed as the beetles will fall in and drown. Common baits include stale beer, molasses and water with yeast, vinegar and overripe fruit from the planting.
What does a strawberry sap beetle look like?
Strawberry sap beetle adults are the smallest (less than 1/8 inch long), oval-shaped, and mottled brown in color. They do not have any clear markings on the wings. Dusky sap beetle adults are 1/8-inch long with short wing covers and are uniform dull black in color.