“Chicharrita” is a common term for leafhoppers, small sap-sucking insects belonging to the family Cicadellidae. Found in diverse environments, they feed on a wide range of plants. Their presence can lead to various plant issues, from direct feeding damage to the transmission of plant diseases.
Understanding the Chicharrita
Description and Life Cycle
Leafhoppers are small, slender, wedge-shaped insects, typically 1/8 to 1/4 inch long, though some reach 1/2 inch. Their coloration varies widely (green, brown, yellow, or mottled patterns). A distinguishing feature is the rows of small spines along their hind legs.
They undergo incomplete metamorphosis: egg, nymph, and adult. Females lay eggs in tender host plant tissues. Nymphs hatch as smaller, wingless versions of adults, developing through five stages by molting. Immature nymphs are found on leaf undersides and can crawl sideways. Adults are agile, jumping or flying quickly when disturbed. The life cycle duration varies by species and temperature, with some completing a cycle in a few weeks and having multiple generations per year.
Common Species and Habitats
Leafhoppers are a diverse group, with over 2,500 species in North America, inhabiting various environments from home gardens to agricultural fields. Many species have a broad host range, feeding on vegetables, fruits, ornamental plants, grasses, and trees. Notable examples include the potato leafhopper (Empoasca fabae), affecting over 200 plant species; the beet leafhopper (Circulifer tenellus), known for affecting vegetables; and the aster leafhopper (Macrosteles quadrilineatus), which targets carrots, lettuce, and celery. They are commonly found on leaf undersides or new shoots.
Impact on Plants
Direct Feeding Damage
Leafhoppers harm plants by piercing tissues and sucking sap, primarily from the phloem or xylem. This feeding removes chlorophyll, causing visible leaf symptoms. Common signs include stippling (small, pale specks) on the upper leaf surface. Heavy infestations can lead to larger bleached blotches, and leaves may curl, yellow, brown, and die.
Some species inject toxins during feeding, causing “hopperburn,” where leaf tips and margins curl, yellow, and become brittle. Continuous sap removal weakens plants, stunting growth and reducing vigor. Seedlings and young plants are particularly susceptible. Additionally, some leafhoppers excrete honeydew, which can lead to black sooty mold on plant surfaces, hindering photosynthesis.
Disease Transmission
Beyond direct feeding damage, leafhoppers are significant pests because many species act as vectors for plant diseases. They transmit various pathogens, including viruses, phytoplasmas, and bacteria, from infected to healthy plants as they feed. This indirect damage is often more destructive than direct feeding injury.
Diseases transmitted by leafhoppers include aster yellows, curly top virus, and corn stunt. Aster yellows causes plants to yellow, dwarf, distort foliage, and produce abnormal shoots. Curly top virus leads to crinkled, dwarfed, and rolled leaves, significantly reducing crop yield. Corn stunt disease results in severe stunting and yellowing of corn plants. These pathogens often obstruct the plant’s vascular system, impeding nutrient transport. The mobility of adult leafhoppers contributes to the rapid spread of these diseases.
Identifying Chicharrita Infestations
Visual Identification of the Pest
Identifying leafhopper infestations involves looking for the insects and their characteristic signs. Adult leafhoppers are small (1/8 to 1/4 inch), slender, wedge-shaped, and vary in color, often blending with foliage. They jump or fly quickly when disturbed, making them elusive.
Nymphs are smaller, wingless, and found on the undersides of leaves, often moving with a distinctive sideways crawl. Pale, papery cast skins from molting can be found on leaf undersides, indicating developing nymphs. Yellow sticky traps are effective for monitoring adult leafhopper populations, as they are attracted to yellow.
Recognizing Plant Symptoms
Recognizing specific plant symptoms is another method for detecting leafhopper infestations or transmitted diseases. The most common symptom of direct feeding is stippling, appearing as tiny white or yellow spots on upper leaf surfaces where chlorophyll has been removed. Leaves may also curl, turn yellow, or brown, with “hopperburn” characterized by browning and crisping of leaf margins.
Beyond direct feeding, symptoms of disease transmission are more severe and varied. Infected plants may exhibit stunted growth, yellowing, distorted foliage, or abnormal shoot production (e.g., corn stunt disease, curly top virus). The presence of honeydew, a sticky excretion, also indicates a leafhopper infestation, often followed by black sooty mold.
Managing Chicharrita Populations
Cultural Practices
Effective management of leafhopper populations begins with cultural practices that create an unfavorable environment. Maintain good garden sanitation by removing overwintering sites like fallen leaves and garden debris. Control weeds, especially those serving as alternative hosts for leafhoppers and their pathogens, to reduce pest populations.
Proper plant spacing allows for better air circulation and reduces humidity, deterring leafhoppers. Crop rotation with non-host plants can disrupt the leafhopper life cycle and prevent population buildup. Reflective mulches around plants can repel leafhoppers by disorienting them. For young or susceptible plants, physical barriers like row covers can exclude leafhoppers, though these should be removed gradually for plant acclimation.
Biological Control
Biological control methods leverage natural enemies to regulate leafhopper populations. Many generalist predators, such as ladybugs, green lacewings, minute pirate bugs, and spiders, feed on leafhoppers and their nymphs. Encouraging these beneficial insects by providing diverse habitats and avoiding broad-spectrum pesticides helps maintain natural control.
Parasitic wasps, such as Anagrus atomus, target leafhopper eggs by laying their own eggs inside them, preventing hatching. Introducing these wasps can reduce leafhopper populations, especially early in the season. While biological controls may not provide immediate eradication, they contribute to a sustainable and balanced pest management system.
Chemical Control
Chemical control, while sometimes necessary for severe infestations, should be a last resort within an integrated pest management (IPM) strategy. Insecticidal soaps are effective against leafhoppers, especially immature nymphs on leaf undersides, by disrupting their waxy coating. Neem oil can disrupt the insect’s hormone system, leading to reduced feeding and mating.
For widespread or persistent infestations, insecticides like pyrethrins or malathion can be used. These are generally more effective on immature leafhoppers, as nymphs are less mobile and more susceptible. Always follow product label instructions precisely, including application rates and safety precautions, to protect beneficial insects and minimize environmental impact. Targeted application to affected areas, such as new growth, can improve efficacy.