Pick up know-how for tackling diseases, pests and weeds.
Farm bill, farm marketing, agribusiness webinars, & farm policy.
Find tactics for healthy livestock and sound forages.
Scheduling and methods of irrigation.
Explore our Extension locations around the state.
Commercial row crop production in Arkansas.
Agriculture weed management resources.
Use virtual and real tools to improve critical calculations for farms and ranches.
Learn to ID forages and more.
Explore our research locations around the state.
Get the latest research results from our county agents.
Our programs include aquaculture, diagnostics, and energy conservation.
Keep our food, fiber and fuel supplies safe from disaster.
Private, Commercial & Non-commercial training and education.
Specialty crops including turfgrass, vegetables, fruits, and ornamentals.
Find educational resources and get youth engaged in agriculture.
Gaining garden smarts and sharing skills.
Creating beauty in and around the home.
Maintenance calendar, and best practices.
Coaxing the best produce from asparagus to zucchini.
What’s wrong with my plants? The clinic can help.
Featured trees, vines, shrubs and flowers.
Ask our experts plant, animal, or insect questions.
Enjoying the sweet fruits of your labor.
Herbs, native plants, & reference desk QA.
Growing together from youth to maturity.
Crapemyrtles, hydrangeas, hort glossary, and weed ID databases.
Get beekeeping, honey production, and class information.
Grow a pollinator-friendly garden.
Schedule these timely events on your gardening calendar.
Equipping individuals to lead organizations, communities, and regions.
Guiding communities and regions toward vibrant and sustainable futures.
Guiding entrepreneurs from concept to profit.
Position your business to compete for government contracts.
Find trends, opportunities and impacts.
Providing unbiased information to enable educated votes on critical issues.
Increase your knowledge of public issues & get involved.
Research-based connection to government and policy issues.
Support Arkansas local food initiatives.
Read about our efforts.
Preparing for and recovering from disasters.
Licensing for forestry and wildlife professionals.
Preserving water quality and quantity.
Cleaner air for healthier living.
Firewood & bioenergy resources.
Managing a complex forest ecosystem.
Read about nature across Arkansas and the U.S.
Learn to manage wildlife on your land.
Soil quality and its use here in Arkansas.
Learn to ID unwanted plant and animal visitors.
Timely updates from our specialists.
Eating right and staying healthy.
Ensuring safe meals.
Take charge of your well-being.
Cooking with Arkansas foods.
Making the most of your money.
Making sound choices for families and ourselves.
Nurturing our future.
Get tips for food, fitness, finance, and more!
Understanding aging and its effects.
Giving back to the community.
Managing safely when disaster strikes.
Listen to our latest episode!
Lonoke County - Kyle Sanders
Prairie County - Amy Greenwalt Tallent
Prairie County- Andrew Sayger
White County - Sherri Sanders
White County - Jan Yingling
Stay Connected
Contact Sherri Sanders at ssanders@uada.edu to sign up for email updates!
by Jan Yingling, CEA - Agriculture
Pecan scab is an important fungal disease caused by the pathogen Cladosporium caryigenum and is generally considered to be the most destructive disease of pecan in most growing regions in the United States. Without management, pecan scab can cause 50-100% losses in susceptible varieties.
Scab is favored by wet and humid conditions, especially prolonged periods of continuous leaf wetness, and can occur on leaves, twigs, and nut shucks. Young and actively growing tissues are the most susceptible to scab and become less susceptible as they mature. The disease first appears as small, dark brown to black spots, which may continue to increase in size, sometimes coalescing into large, irregularly shaped, lesions.
Infection is more often seen on the lower leaf surface, but both sides of the leaf may be infected. Leaf infection can cause a reduction in photosynthetic output, but nut shuck infection causes the majority of losses linked to scab.
When early infection of the nuts occurs, trees may experience significant premature nut drop as well as a reduction in nut size and quality. As the season progresses, initial nut scab infections become less damaging to yield and quality, with damage mostly being cosmetic, if the disease develops after shell hardening. The likelihood of nut drop increases greatly if lesions cover more than 50% of the shuck and may also result in nuts that remain on the tree or will not separate from the shuck.
Pecan scab can be managed through cultural methods such as removing fallen branches from the orchard floor and pruning trees to increase air circulation, planting scab-resistant varieties, and following a fungicide spray program. Scab severity can vary greatly from year to year, so frequent scouting of orchards and being observant of weather conditions are essential tasks to stay ahead of scab development.
See how we use SensorPush to collect weather data to determine pecan scab application timing.
When relative humidity is above 90% and the temperature is above 70° F, conditions are very favorable for pecan scab development. Each pecan variety has its own level of resistance, so a method for determining spray intervals has been developed using accumulated pecan scab hours.
Accumulated scab hours are calculated by totaling the number of hours where both 90% relative humidity and 70°F temperatures occur at the same time, resetting the calculation after each fungicide application. The model assumes that the crop will be protected for 14 days following a properly applied fungicide application. Thresholds have been set at 10 scab hours for highly susceptible varieties, 20 hours for moderately susceptible varieties, and 30 hours for less susceptible varieties.
If the threshold is met within the two-week period following a spray, it will be necessary to reapply. If the threshold has not been met, it may be possible to delay the next application until the hours have been met. It has been shown that using the scab hour model rather than simply spraying on a fixed schedule can reduce the number of fungicide applications required in many crop years.
Go to https://pecanscab.uada.edu/ to use the Pecan Scab Hour Calculator.