Lerps are tiny sap-sucking insects that can infest and damage bald cypress trees As a bald cypress tree owner, it’s important to know how to identify and get rid of lerps in order to protect the health and appearance of these beautiful trees In this comprehensive guide, I’ll explain what lerps are, the damage they cause, and effective organic and chemical treatment methods for controlling lerps on bald cypress trees.
What are Lerps?
-
Lerps are juvenile insects in the psyllid family that feed on sap from leaves and stems of host trees.
-
They produce a protective covering over themselves made of sticky honeydew secretions and shed exoskeletons. This covering disguises and shields them.
-
Lerps infestations often indicate an underlying stress or health issue in the tree
-
If uncontrolled, lerps can weaken and potentially kill bald cypress trees through extensive sap feeding. Their sticky honeydew also promotes sooty mold growth.
Signs of Lerps Infestation
-
Small (1mm) yellow, white or brown flakes on leaves and stems. This is the protective lerp covering.
-
Leaves may be sticky, wilted or yellowing. Twig dieback may occur.
-
Presence of sooty mold on leaves and branches. This black fungal growth feeds on lerps’ honeydew secretions.
-
Ants, wasps, birds may be seen frequenting the tree to feed on lerps.
-
Stunted growth, leaf drop and other signs of plant stress.
Organic Lerps Control Methods
Remove lerps by hand
- Manual removal of lerps is effective for light infestations. Scrape off lerps using gloved fingers or an old toothbrush.
Use strong water spray
- Dislodge lerps by spraying leaves and stems with a high-pressure stream of water. Repeat regularly.
Apply horticultural oils
- Coating leaves with neem, canola or cottonseed oil smothers lerps and disrupts their growth.
Encourage natural predators
- Attract beneficial insects like ladybugs, lacewings and parasitic wasps that prey on lerps.
Improve tree health
- Reduce stress and increase vigor through proper watering, mulching, pruning, fertilization. A vigorous tree better resists lerps.
Chemical Treatment for Heavy Lerp Infestations
-
Insecticidal soaps – Kill lerps on contact while safer for beneficials than pesticides.
-
Systemic insecticides (acetamiprid imidacloprid) – Applied to roots or soil to kill lerps feeding on sap. Use only as a last resort.
-
Horticultural oil dormant spray – Controls overwintering lerp populations.
-
Always follow label directions. Monitor for effectiveness and toxicity.
Preventing Lerps from Returning
-
Inspect trees weekly during growing season to detect lerps early before they multiply.
-
Remove and destroy any branches and leaves with lerps immediately.
-
Keep trees healthy with proper care practices to avoid stress.
-
Promote air circulation and sunlight with proper spacing and pruning.
-
Control ants which may tend and protect lerps. Apply sticky barriers on trunk.
Lerps can be damaging sap-feeding pests on stressed bald cypress trees. Keep a vigilant eye out for signs of infestation. Removing lerps by hand and improving tree health organically often provides adequate control. For severe cases, targeted application of insecticidal soaps or oils may be warranted. Combining early detection, prompt organic and chemical treatment as needed, and prevention through proper tree care is key to successfully ridding your beloved bald cypress trees of destructive lerps.
Cypress Twig Gall Midge: Taxodiomyia cupressiananassa
Recognition: Heavy, spongy galls of varying sizes are created when female flies lay their eggs on newly developing leaves. The oval, green galls are heavy enough to cause branches to droop under their weight if there are too many on the branch. Each gall may contain up to 15 yellow-orange maggots in individual cells. In the autumn, the galls turn brown and drop to the ground with the leaves, and the larvae over-winter in the gall. The adults emerge as flies and can be found for about a month beginning in mid-May. There are two generations per year.
Contributing Factors: The main contributing factor of cypress twig gall midges is previous infestations of this insect.
Management Recommendations: To reduce the number of galls in a new season, rake and destroy the fallen leaves and galls. Sprays can be directed at adults when they are scouted, but there are many natural enemies and biological controls of this insect (Gomez and Mizell 2013).
Recognition: Mealybugs are soft-bodied insects with piercing-sucking mouthparts and a wooly, white, waxy covering. A byproduct of mealybug feeding is sticky honeydew, which coats infested foliage and provides a medium for growth of black sooty mold fungi. Mealybug reproduction is increased in humid and hot environments.
Contributing Factors: Contributing factors for mealybugs, specifically for Baldcypress, is unknown.
Management Recommendations: Predators (like lady bug larvae) can control many mealybug infestations in the landscape. The waxy covering protects the insects from sprays. Horticultural oils or systemic insecticides can be effective in controlling mealybugs, but because Baldcypress is very sensitive to horticultural oils, extreme caution should be used when making the decision to apply (UF/IFAS 2015).
Recognition: The Baldcypress Rust Mite is a microscopic eriophyid mite, most active during the warm season, which causes browning of interior needles. It overwinters in bark crevices, ready to reproduce and infest new growth in the spring. The mites mouthparts rasp the leaf cells, causing the needles to become yellowish and then brown. Mites can be seen with a 10-power hand lens, and their white cast skins are the best diagnostic.
Contributing Factors: Warm weather causes very rapid reproduction.
Management Recommendations: Carbaryl, dicofol, and oxythioquinox will knock down this mite with thorough foliage coverage (Nixon and Sheltar 1998). Please consult the most up-to-date regulations before applying any pesticides.
Key Plant: Baldcypress (Taxodium distichum)
Baldcypress (Taxodium distichum (L.) Rich.) are deciduous-needled pyramidal trees that can reach 100 to 150 feet in height. They grow at a moderately fast rate, reaching 40 to 50 feet in the first 15 to 25 years. They are commonly found throughout the state of Florida, particularly near lakes and rivers (as they are native to wetlands along running streams), and can also be found throughout most of the eastern United States in USDA hardiness zones 5A through 10B. Growth is fastest on moist, well-drained soils in full sun. Trees are highly tolerant of drought, although they are adapted to thrive in wetlands, where they will develop “knees,” a distinct structure that forms above the roots. They will also grow well in upland sites with few to no “knees” (Gilman and Watson 2014).
This series of Key Plant, Key Pests publications is designed for Florida gardeners, horticulturalists, and landscape professionals to help identify common pests associated with common Florida flora. This publication, the first in the Key Plant, Key Pests series, helps identify the most common pests found on the Baldcypress (Taxodium distichum).
This publication provides information and general management recommendations for the cypress leaf beetle, fall webworm, cypress twig gall midge, mealybugs, rust mites, and needle blights. For a more comprehensive guide of woody ornamental insect management, download the current Professional Disease Management Guide for Ornamental Plants here or the Integrated Pest Management in the Commercial Ornamental Nursery Guide here.
It may look DEAD, but it’s not! Bald Cypress Trees: Are my trees dead?? (Tree: Lindsey Skyward)
FAQ
How to get rid of LERP?
How to get rid of psyllids naturally?
How to treat bagworms on bald cypress trees?
How do you care for a bald cypress tree?
It’s not difficult to provide your tree the best bald cypress care if you select an excellent planting location, starting with a spot in full sun. When you are planting a bald cypress tree, ensure that the soil has good drainage but also retains some moisture. Ideally, the soil should be acidic, moist and sandy. Irrigate regularly.
Do bald cypress trees get chlorosis?
Although bald cypress information may tell you that the tree has no serious insect or disease issues, it is likely to get chlorosis in alkaline soils. You’ll make Mother Nature happy if you start bald cypress growing. These trees are important to wildlife and help hold soil in place.
Does a bald cypress tree have a taproot?
Bald Cypress Trees have a taproot as well as horizontal roots that do not tend to cause a lot of foundational damage. One unique aspect of the Bald Cypress Trees’ roots is that they can form “knees.” These knees are structures of the root system that rise above the ground as an extension of the root.
How long do bald cypress trees live?
When you start planting a bald cypress tree in your backyard, try to imagine the tree several decades in the future at 120 feet (36.5 m.) tall with a trunk diameter of 6 (1.8 m.) feet or more. The other piece of bald cypress information to keep in mind involves their longevity. With appropriate bald cypress care, your tree may live 600 years.