Pests and Diseases
Pests and diseases can decimate agronomic crops and result in huge financial losses. Make use of Penn State Extension’s substantial library of resources including recommendations for managing weeds, insects, and disease pests in a variety of agronomic crops. Find tips on dealing with bacteria, molds, fungal diseases, and rot.
Agronomic Crops Diseases and Integrated Pest Management
There are several ways to deal with pests. If you want to use pesticides on your agronomic crops you may need a license. To maintain a valid applicator’s license in Pennsylvania, private pesticide applicators must fulfil a continuing education requirement. Penn State Extension provides a number of workshops for anyone looking to become certified or recertified. They include Agronomic Pesticide Update workshops, an online course covering What's New in Agronomic Pest Control, and an Agronomic Pesticide Update Webinar. The Penn State Agronomy Guide also covers pest management.
Many different pests can affect agronomic crops; for example, slugs are a challenging pest for no-till farmers. New herbicide products are regularly released making pest management even more demanding. It’s not something crop producers have to face on their own. Certified crop advisers can help producers with pest management as well as studying soil and water, crop, and nutrient management.
Common Corn Pests and Diseases
A number of different pests and diseases can affect corn crops at various growth stages. Mild temperatures and increased humidity, for example, can lead to corn leaf blight and gray leaf spot. Corn ear rot and mycotoxins can also be a problem when humidity is high. Knowing what corn diseases to look for means you can make the right decisions on what to spray, and indeed whether to spray at all.
As well as combating diseases, corn producers also have a number of pests to contend with. An increase in reduced-tillage culture and planting corn into sod and small grain cover crops has led to an increase in armyworm damage.
Several species of billbugs feed on corn plants causing damage in May. The adults chew small holes in the stems which can severely retard or even kill small plants.
Pests that cause damage below ground can be challenging to control, particularly in corn production. Crop rotation is one way to reduce numbers. The seedcorn maggot is one example.
Common Soybean Pests and Diseases
Soybean production has steadily been increasing in Pennsylvania. Being able to assess soybean fields for insect damage and learning how to recognize soybean pests are important factors for successful and profitable agronomic crop production. The soybean aphid, for example, is an exotic pest of soybean that can heavily stress plants, leading to a reduction in yields of up to 40%.
Soybean diseases such as stem canker, brown stem rot, and sudden death syndrome can also wreak havoc on soybean crops.
Wheat and Small Grains Common Pests and Diseases
For wheat and small grains producers, there is the added complication of pests being present in stored grain. The Angoumois Grain Moth, for example, can make grain smell unpleasant, making it less attractive for consumption. Foreign grain beetles are a fungus-feeding insect commonly found in grain stored on farms in Pennsylvania. The sawtoothed and merchant grain beetles are two more pests that can contaminate stored grains.
Effective control of stored grain pests requires an IPM approach that combines sanitation, identification, monitoring, and preventive practices.
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NewsWhite Mold Risk and Management in 2025
Date Posted 6/24/2025This year poses challenges for predicting white mold risk in soybean. -
ArticlesHome Stretch: Evaluating Your Small Grain Crops
We are at a point in the season to determine your small grain crop’s potential for quality and yield as we approach harvest. -
ArticlesEarly Season Soilborne Diseases of Soybean
The combination of cold temperatures and wet soil conditions can increase the risk of soybean soilborne diseases. -
News2025 Pennsylvania Slug Monitoring Project
Date Posted 6/10/2025Last weekly slug update for 2025. -
ArticlesHow to Become an Aerial (Drone) Pesticide Applicator
Learn about the requirements and certification process of becoming an aerial pesticide applicator. -
NewsWatch for Black Cutworm and Bean Leaf Beetle
Date Posted 6/3/2025Scout for black cutworm in corn fields, and watch for damage from bean leaf beetle on your emerging soybean plants. -
NewsInsect Update: Black Cutworm and Potato Leafhopper
Date Posted 5/27/2025In some parts of Pennsylvania, it is time to scout for black cutworm damage in corn and potato leafhoppers in alfalfa. -
NewsDon't Sleep on Head Scab in 2025
Date Posted 5/27/2025Check in on your small grains as they move through reproductive stages. -
NewsScout for Black Cutworm Damage and Cereal Leaf Beetle
Date Posted 5/20/2025In southeastern PA, there is a heightened risk of damage from black cutworm, so now is the time to begin scouting for their cutting damage in corn fields. Across PA, folks should scout for cereal leaf beetle, mostly in wheat and oats. -
NewsAlfalfa Weevils in Eastern PA May Be Resistant to Pyrethroid Insecticides
Date Posted 5/13/2025Numerous reports suggest that applications of pyrethroids in some fields failed to control alfalfa weevil populations -
ArticlesHow to Find Pesticide Applicator Certification Exams
Find dates and locations for pesticide applicator certification exams on the Pennsylvania Department of Agriculture's PaPlants website. -
NewsDeer Management in Pennsylvania
Date Posted 5/6/2025White-tailed deer damage crops across Pennsylvania. Here are five deer management programs from the PA Game Commission. Work with your local game warden for effective, long-term deer control on your farm. -
NewsSignificant Flights of Black Cutworm Moths Arriving in Some Parts of PA
Date Posted 5/6/2025Our first significant flights of black cutworm moths arrived in three counties in recent days. -
NewsExpired Pesticide License?
Date Posted 5/6/2025Has your pesticide license lapsed or expired and what is the difference? The following are simplified instructions for reinstating your lapsed or expired pesticide license. -
NewsInsect Update: Three Insect Pests to Consider
Date Posted 4/29/2025A variety of pests are active as the growing season progresses; we will address alfalfa weevil, black cutworm, and cereal leaf beetle. -
ArticlesScouting Small Grains Diseases for Improved Fungicide Decision Making
Commit to scouting and growth staging your small grain to understand if the disease intensity warrants a fungicide application. -
ArticlesIs Soybean Cyst Nematode Lurking in Your Soil?
Spring is a great time to test your fields for the presence of soybean cyst nematode (SCN). -
NewsScouting is Key to Insect Pest Management in Spring
Date Posted 4/15/2025As spring pests become active, remember that scouting is the key to detecting insect-pest populations and determining whether insecticides will be helpful. -
ArticlesSpotted Lanternfly Management and Pesticide Safety
Lycorma delicatula, commonly known as the spotted lanternfly (SLF), is an invasive insect pest present in Pennsylvania and some other eastern states. SLF threatens grape production and tree health and is a nuisance in landscapes. -
Articles¿Tiene Piojos? Elimine los Piojos con MIP
¿Qué harÃa usted si la escuela de su niño lo envÃa de vuelta a su casa porque tiene piojos? -
Articles¿Tiene Hormigas? Elimine las Hormigas con MIP
El manejo integrado de plagas (IPM) utiliza la información sobre plagas para elegir los métodos de control más seguros y efectivos. -
NewsEarly Spring Weeds in No-Till Fields
Date Posted 4/1/2025As the weather warms, weeds grow quickly. Below is an overview of commonly found weeds during the early spring season, especially in no-till settings. -
NewsFlexible Burndown Herbicide Programs for Corn or Soybean
Date Posted 4/1/2025Certain herbicides provide flexibility if you need to switch between corn or soybean crops. -
NewsAlfalfa Weevil Larvae Are Becoming Active in Alfalfa Fields
Date Posted 4/1/2025Alfalfa weevil larvae are becoming active, particularly in southern counties and south-facing fields. Scout your fields to detect their damage. -
NewsWinter Grain Mites are Being Found in Triticale and Rye Fields
Date Posted 4/1/2025Populations of this pest species, which are becoming more common in Pennsylvania, can grow in fields planted annually with small grains.



