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When growers and landscape professionals think about insects, the first thought is often pests and the damage they cause. However, not all insects are harmful. Many beneficial insects play an important role in naturally suppressing pest populations in greenhouses, nurseries, and landscapes. These “good bugs” are valuable partners in Integrated Pest Management (IPM) programs and can help reduce reliance on chemical insecticides. Beneficial insects are a key component of Integrated Pest Management (IPM) programs. They help suppress pests naturally and can improve long-term pest management success when properly conserved or introduced into production systems. Two important groups of beneficial insects are predators and parasitoids. Predators actively consume pests throughout their life cycle. Common examples include lady beetles, green lacewings, minute pirate bugs, predatory mites, and hover fly larvae. These natural enemies feed on aphids, whiteflies, spider mites, scales, thrips, and other soft-bodied pests commonly encountered in Texas greenhouses and landscapes. Parasitoids are specialized insects, usually tiny wasps, that develop inside or on a host insect and eventually kill it. Several parasitoid species are commercially available and widely used in greenhouse biological control programs, especially for whitefly and aphid management. Parasitoids are specialized insects, usually tiny wasps, that develop inside or on a host insect and eventually kill it. Several parasitoid species are commercially available and widely used in greenhouse biological control programs, especially for whitefly and aphid management. Greenhouse environments often provide ideal conditions for biological control because temperature, humidity, and pest populations can be monitored more closely. In landscapes and nurseries, conserving naturally occurring beneficial insects can also provide significant pest suppression over time. Unfortunately, beneficial populations are frequently disrupted by unnecessary or repeated applications of broad-spectrum insecticides. One of the biggest challenges in pest management is recognizing when beneficial insects are already helping control a pest problem. In some situations, professionals may apply insecticides before evaluating predator or parasitoid activity. This can eliminate natural enemies and create secondary pest outbreaks or pest resurgence. In addition, repeated use of the same insecticide groups can contribute to pesticide resistance, making future pest management more difficult. Scouting remains one of the most important tools in preserving beneficial insects. Correct identification of both pests and beneficials allows professionals to make informed treatment decisions. When insecticide applications are necessary, selecting reduced-risk or selective products can help preserve natural enemy populations while still managing key pests. Habitat also plays a role in supporting beneficial insects. Flowering plants, reduced dust, proper irrigation management, and minimizing unnecessary pesticide exposure can all encourage beneficial activity in landscapes and production systems. Biological control is not always a complete replacement for insecticides, but it is an effective management tool when incorporated into a broader IPM strategy. As greenhouse and landscape industries continue to face challenges from invasive pests, environmental concerns, and pesticide resistance, beneficial insects should not be viewed as forgotten tools. Instead, they should be recognized as valuable partners in sustainable pest management programs. Photo credit: Rafia Khan, Ph. D. Assistant Professor and Extension Specialist Texas A&M AgriLife Research and Extension Center Overton, TX. 
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Spring in Texas often brings warm temperatures along with frequent rain and storm events, creating highly favorable conditions for increased pest pressure in nurseries, greenhouses, and landscape systems. Elevated humidity and excess moisture significantly enhance pest development, survival, and reproduction, making this season particularly challenging for growers. These environmental conditions not only accelerate pest life cycles but also create ideal microhabitats for hidden and soil-associated pests, increasing the risk of sudden infestations and economic losses. Favorable Conditions for Pest OutbreaksSoft-bodied insects such as aphids, whiteflies, and thrips thrive under warm, humid conditions commonly observed during spring. The flush of new plant growth during this period provides tender, nutrient-rich tissues that are highly attractive for feeding and reproduction. As a result, pest populations can increase rapidly within a short period, often going unnoticed until visible damage appears. Without timely monitoring and intervention, these pests can quickly reach damaging levels and affect plant quality and marketability. Soil and Moisture Associated Pests Prolonged wet conditions create ideal environments for pests such as fungus gnats and shore flies, particularly in greenhouse and nursery production systems. Their larvae develop in moist growing media, feeding on organic matter and plant roots, which can weaken plants and reduce overall vigor. Additionally, pests like the European pepper moth benefit from high moisture conditions, as their larvae remain concealed in the lower canopy or within the growing media. This hidden feeding behavior, combined with favorable environmental conditions, makes early detection difficult and allows populations to build up before noticeable symptoms appear. Pest Spread and Increased Activity Rainfall and storm events can also contribute to the spread of pests within production systems. Splashing water can move infested soil, plant debris, eggs, and larvae between containers or across growing areas, facilitating rapid dispersal. Furthermore, outdoor pests such as caterpillars and beetles often become more active following rainfall, increasing feeding activity and the likelihood of damage. Wind and storm movement can also aid in dispersing adult insects into new areas, compounding pest pressure. Challenges in Pest Control Frequent rainfall presents additional challenges by reducing the effectiveness of insecticide applications. Rain can wash off residues from plant surfaces, shortening the duration of control and requiring more precise timing of applications. High humidity may also affect product performance and pest exposure, making control less consistent during extended wet periods. Take-Home Message Overall, rainy spring weather creates ideal conditions for pest outbreaks by enhancing survival, reproduction, and spread, while simultaneously reducing control effectiveness. Under these conditions, consistent scouting, proper irrigation management, and timely, integrated interventions are essential to minimize pest impact and maintain plant quality and marketability. Rafia Khan, Ph. D. Assistant Professor and Extension Specialist Texas A&M AgriLife Research and Extension Center, Overton, TX
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Click the + button to zoom in. If part of the page is cut off, click on the page and slide it left or right to see more. On a phone or tablet, use two fingers to zoom in and move around the page. Any links you see are clickable. For the best view, click the full screen icon (⛶) in the bottom right. Want a copy? Click the download button to save it. (to the left of the magnifying glass) Rafia Khan, Ph. D. Assistant Professor and Extension Specialist Texas A&M AgriLife Research and Extension Center Overton, TX. Crape myrtle bark scale (CMBS), Acanthococcus lagerstroemiae, has become a persistent and economically important pest of crape myrtle in Texas landscapes and nurseries. Early spring is a critical time to detect and manage this pest before populations build and become more difficult to control. Identification and Early SignsCMBS primarily colonizes trunks, branches, and twigs of crape myrtle. The most recognizable sign is the presence of small, white to gray, felt-like encrustations on the bark. These are the adult females, which produce a waxy covering that protects them from environmental stress and some control measures. One of the earliest and most noticeable symptoms in spring is the development of black sooty mold on the bark and surrounding surfaces. This mold grows on honeydew excreted by the feeding scales and often serves as the first visual cue for infestation. Heavy infestations can lead to reduced plant vigor, poor flowering, and aesthetic decline, key concerns for both growers and landscape managers. During early spring, overwintering populations begin to resume activity. Crawlers (the mobile, immature stage) start emerging as temperatures increase, making this the most vulnerable stage for management interventions. Monitoring StrategiesRegular scouting should begin in early spring (March–April in most parts of Texas). Inspect the bark closely, especially in crevices and around pruning cuts. Look for both the white scale coverings and the associated sooty mold. To detect crawler activity, double-sided tape can be wrapped around infested branches. The presence of tiny pinkish crawlers on the tape indicates active emergence and signals the optimal timing for certain treatments. Management ApproachesAn integrated pest management (IPM) approach is essential for effective CMBS control. Cultural and Mechanical Control: Light infestations can be managed by physically removing scales using a soft brush or by washing the bark with a strong stream of water. Pruning heavily infested branches can also reduce pest pressure, but care should be taken to properly dispose of infested material. Chemical Control: Early-season applications are most effective when targeted at the crawler stage. Contact insecticides (e.g., horticultural oils or insecticidal soaps) can help suppress crawler populations when coverage is thorough. These treatments should be applied when temperatures are moderate to avoid plant injury. Systemic insecticides, such as those containing dinotefuran or imidacloprid, can provide longer-term control. Soil drenches or trunk applications applied in spring, allow the active ingredient to move within the plant and target feeding scales. However, timing is critical; applications should be made early enough to coincide with active feeding. ConclusionEarly detection and timely intervention are key to managing crape myrtle bark scale. By combining careful monitoring with targeted cultural and chemical controls, growers and landscape professionals can minimize damage and maintain the health and aesthetic value of crape myrtle plantings throughout the growing season.
Figure: Crape myrtle bark scales on crape myrtle plants (A), Black sooty mold on the leaf and stems on infested crape myrtle plants (B). Photo credit: Rafia Khan
Rafia Khan, Ph. D. Texas A&M AgriLife Research and Extension Center Overton, TX. Spring is the most important production and sales season for Texas nurseries, and thoughtful preparation during late winter can significantly influence crop quality, pest pressure, and overall profitability. As temperatures begin to rise, the priority should be a thorough inspection of all overwintered plant material. Carefully examine plants for cold injury, root health issues, nutrient deficiencies, and early signs of insect or disease activity. Pests such as aphids, mites, whiteflies, and scale insects often establish tender new growth early in the season. Removing dead, damaged, or heavily infested plants reduces overwintering populations and minimizes the risk of rapid outbreaks once favorable conditions develop.
Equipment readiness is equally critical. Before spring applications begin, calibrate sprayers, fertilizer spreaders, and chemigation systems to ensure accurate delivery rates and uniform coverage. Check nozzles for wear, confirm pressure settings, and repair leaks. Proper calibration not only improves pest control efficacy but also prevents phytotoxicity, reduces product waste, and ensures compliance with label requirements. This is also a good time to review pesticide inventory and verify that products are properly stored and within expiration dates. Updating and reinforcing your Integrated Pest Management (IPM) program should be part of spring preparation. Establish a consistent scouting schedule and designate trained personnel responsible for monitoring crops. Use tools such as sticky cards, pheromone traps, and regular plant inspections to detect pest activity early. Accurate identification and threshold-based decision-making allow for targeted treatments and help prevent unnecessary applications. Early detection remains one of the most cost-effective pest management strategies in nursery production. Inspect irrigation systems before peak demand by checking drip lines, emitters, sprinklers, and pumps for leaks or uneven distribution, as poor irrigation can stress plants and increase susceptibility to disease and pests. Test growing media for pH and soluble salts, and ensure fertilization programs, especially controlled-release fertilizers, are properly applied to support healthy growth. Implement early weed control with uniform pre-emergent applications and winter weed removal to reduce competition and pest reservoirs. Provide staff with refresher training on scouting, safety, equipment use, and recordkeeping. A well-organized spring plan strengthens plant health, reduces pest pressure, and supports a successful nursery season. Rafia Khan, Ph. D. Texas A&M AgriLife Research and Extension Center Overton, Tx. Winter freezes often bring hope that cold weather will eliminate insect pests in landscapes and nurseries, offering a natural reset before the next growing season. After several nights of subfreezing temperatures, it is common to expect fewer insects and reduced pest pressure in spring. While freezing temperatures can suppress or temporarily reduce some exposed pest populations, they rarely provide complete control. Many insects are surprisingly resilient and well-adapted to surviving winter conditions through protective behaviors and physiological adaptations, allowing them to rebound quickly once temperatures warm.
Insects are exothermic or cold-blooded; their activity slows as temperatures drop. Feeding, reproduction, and development pause, and extreme cold can kill exposed individuals. However, many species avoid lethal temperatures by seeking protection in soil, mulch, bark crevices, plant crowns, or greenhouse structures. These microhabitats stay warmer than the surrounding air, thereby improving survival. Many insects can survive through dormancy (diapause) or by producing “antifreeze” compounds such as glycerol, sorbitol, antifreeze proteins, etc. that protect their tissues from freezing injury. Eggs, pupae, scales, borers, and soil-dwelling pests are especially resilient. As a result, even after a hard freeze, enough individuals often survive to quickly rebuild populations in spring. Freezes may temporarily suppress exposed pests such as aphids or caterpillars, but they should not be relied upon as a primary management tool. Warmer temperatures can lead to rapid reproduction and early-season outbreaks. Instead, winter is an ideal time to strengthen integrated pest management (IPM) practices. Remove plant debris, prune heavily infested branches, inspect bark and crowns for overwintering stages, and consider dormant oil applications for scales, mites, and aphids. Continue monitoring in greenhouses where pests may survive year-round. Rafia Khan, Ph.D. Assistant Professor and Extension Specialist Texas A&M AgriLife Research and Extension Center, Overton, TX Winter can feel like a break from pest pressure, but for nursery and greenhouse growers, many insects are still present and waiting for the right conditions. Protected structures, mild winter weather, and overwintering life stages allow many pests to survive on plants, in pots, in growing areas, in debris, and in weeds. If these pest populations are not addressed, they often resume early and aggressively in spring. Common winter pests include aphids, thrips, mealybugs, scale insects, whiteflies, spider mites, and greenhouse moth pests such as the European pepper moth. These insects can survive on plant material, in potting media, or within greenhouse structures, often going unnoticed until populations increase. Programmed scouting remains the foundation of winter Integrated Pest Management (IPM). Monitoring efforts should be focused on current in-house plants and newly arrived plant material. Inspect leaf undersides, stems, and growing points, and use sticky cards to detect flying insects early. Cultural practices play a key role in reducing pest pressure during winter. Sanitation, such as the removal of plant debris, leftover shipped plants, weeds, volunteer plants, and unused containers, should be removed from the production sites as they may harbor pests. Manage irrigation carefully to avoid conditions favorable for fungus gnats and root pests, and inspect incoming plants before placing them into production areas. When treatments are necessary, applying products strategically and rotating insecticide modes of action helps protect product performance and avoid costly resistance issues. Winter is also the best time for growers to step back and evaluate what worked and what didn’t during the past season. Reviewing pest records, adjusting management plans, and training employees to recognize early pest signs can pay off quickly. Investing time in winter pest management reduces carryover populations, improves plant quality, and helps operations enter spring with fewer surprises and lower control costs. Figure: Some greenhouse pests in winter. European pepper moth larva (A) and adult (B), Thrips (C), and mealybug (D) Rafia Khan, Ph.D. Assistant Professor and Extension Specialist Texas A&M AgriLife Research and Extension Center, Overton, TX Texas A&M AgriLife Extension is working on publishing a series of educational articles to assist homeowners and green industry professionals in recognizing and managing two recently confirmed invasive insect pests in Texas: the two-spot cotton leafhopper (Amrasca biguttula) and the short-spined thrips (Thrips parvispinus). These pests pose emerging risks to ornamental plants by affecting plant health, appearance, and market value.
The planned articles will provide clear descriptions of pest identification and injury patterns to support early detection. Feeding by the two-spot cotton leafhopper causes a condition known as “hopperburn,” characterized by leaf curling, yellowing, bronzing, reduced vigor, and, in severe cases, plant death. This pest attacks a wide range of ornamental hosts, including hibiscus, and is often difficult to detect due to its small size and concealed feeding behavior. Short-spined thrips are tiny, highly polyphagous insects that feed on numerous ornamental crops, including annual bedding plants and tropical ornamentals. Their feeding leads to foliar scarring, distorted shoots, flower drops, and stunted growth, resulting in reduced plant quality and marketability. In addition to injury symptoms, the articles will summarize current regulatory actions, including quarantine measures and inspection efforts implemented by regulatory agencies to limit pest movement and spread. Management options discussed will be based on science-based recommendations developed from research conducted by other researchers and institutions, with an emphasis on integrated pest management (IPM) strategies such as monitoring, sanitation, cultural practices, and targeted chemical controls when necessary. Through these publications, Texas A&M AgriLife Extension aims to improve awareness, encourage early reporting, and promote informed decision-making. By providing timely, research-informed guidance, Extension seeks to help homeowners and professionals reduce the impact of these invasive pests and protect the long-term sustainability of Texas landscapes and ornamental production systems. Practical GuideThe Texas Department of Agriculture (TDA) has issued an emergency quarantine to prevent the spread of the invasive Cotton Jassid or Two-Spot Cotton Leafhopper, a destructive pest first detected on imported hibiscus plants. The quarantine currently applies to all Hibiscus species, but may expand to include additional host plants as more data becomes available. The quarantine currently covers shipments from Alabama, Florida, Georgia, Louisiana, Mississippi, Tennessee, South Carolina, and North Carolina, where the pest has been detected. It also applies to Texas counties where detections have occurred, halting the movement of hostable plants without required phytosanitary documentation Current Quarantined Texas Counties
Conditions for MovementNo regulated articles may move from or within quarantined areas except under the following conditions:
➡️ Violations are subject to penalties under the Texas Agriculture Code, including fines up to $4,000 per violation, seizure or destruction of articles at the owner’s expense, and potential criminal charges. Management Recommendations (Non-Regulatory) While the quarantine focuses on movement control, TDA and Texas A&M AgriLife recommend the following Integrated Pest Management (IPM) strategies in infested areas:
TNLA Member Update TNLA is in close communication with TDA’s Plant Quality Division and Texas A&M AgriLife Extension entomologists to ensure the industry has up-to-date guidance and clear compliance information.
Members are encouraged to:
👉 Learn more and view TDA’s current quarantine notice. The two-spot cotton leafhopper (Amrasca biguttula) has recently been detected in Texas, traced to hibiscus shipments from out-of-state. This pest is already appearing in retail environments and poses a serious risk to ornamental plants and crops.  Why This Matters
What You Should Do We are asking all industry professionals to share this alert with retailers, growers, suppliers and landscapers in your network. Early identification and coordinated action are essential to prevent this pest from becoming established in Texas. Retailers:
TNLA is monitoring this situation closely and will share updates as they develop. Early identification and coordinated action are critical to preventing widespread establishment in Texas. For additional background, you may also review the Florida pest alert issued late last year. FREE Upcoming Webinar – Save the Date Two-Spot Cotton Leafhopper: What Texas Needs to Know Friday, September 5, 2025 | 12:00 PM CST Presenter: Dr. Rafia Khan, Texas A&M AgriLife Extension Dr. Khan will cover identification, early warning signs, and management practices for protecting plants and operations Register Here Questions? Curtis Smith, Director of Legislative & Regulatory Affairs [email protected] | (409) 673-6048 Thank you for helping us spread the word and protect Texas’ green industry. |
AuthorKim Cabrera, TNLA Marketing Manager Archives
May 2026
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