A fungus called scab makes it difficult to grow pecans. There is hope though, some less common varieties could have you harvesting healthy nuts.
"Our main limiting problem is a fungal disease called scab. When you get scab that's when your leaves start turning black and your tree defoliates by August," Auburn Horticulturist Bryan Wilkins told us.
At the Gulf Coast Research and Extension Center in Fairhope, Wilkins is working to introduce different varieties of pecans to combat the fungal disease.
"The only way to get rid of scab is to spray it and you've got to have a tractor air blast sprayer that will push the spray all the way up through the tree to top of the tree," Wilkins said.
Common pecan trees the most vulnerable
The most common variety of pecans is called desirable. So named for the large nuts they produce. Problem is, the trees need to be grown on an industrial scale because they are the most susceptible to scab. To be viable, they need to be sprayed often, an expensive process that has to be done by licensed professionals.
"You could go to one of the big box stores and buy a pecan and all it's going to say on the tag is pecan tree. You don't know if you're going to get desirable, which is one of the worst scabbing varieties you can get which you will never produce a nut on without spraying," Wilkins told us.
Scab tolerant pecan trees
Wilkins research at the center in Fairhope is showing there is hope. Some less common types of pecan trees have more resistance to scab.There's McMillan; Gafford; Amling; Lakota; and Elliot. These all have shown a high tolerance to scab.
To get one of those you'll have to go to nursery that knows which type they're selling. That way you'll get a tree that can produce a lifetime of healthy pecans.