News from the Tennessee Valley Living Today

Scab-free pecan trees are ideal

"Jerry, what are these black spots on my pecans?"

I would like to have a wheelbarrow full of money for every time I've heard that question. In fact, I discussed such a problem with former Decatur mayor Bill Dukes, along with some watery pecan problems, just a few weeks ago.

What causes black spots on pecan fruit? And what can a homeowner do about it? We'll take a shot at it here and now.

Black spots are tell-tale signs of the fungal disease called "pecan scab." It can severely defoliate pecan trees during wet years, and this sad story can happen even when a person is spraying fungicides. The rains just wash them off. Sadly the immature nuts are likely to fall off way before they're ready for pecan pies. Likely they'll not be filled out inside or will otherwise be ruined when you crack them open. And that's aggravating. Besides, spraying fungicides is out of the question for most homeowners with large pecan trees at home.

So what to do? Glad you asked.

Since you're not likely to want to replace an ancient, slow-growing pecan tree that has scab problems, here are your weapons: Fertilize, deep-water during nut-fill time if there is no rain (August-September), and rake up and destroy fallen nuts, hulls, leaves and tree debris that can harbor the fungal spores. This will not likely cure all the problems, but it sure should help.

For new pecan trees, Bill Goff at Auburn University recommends planting scab-resistant cultivars. This is important for a homeowner. Recommended varieties with good resistance include Elliot, Jenkins, Gafford, McMillan and Carter. Check the Website at "" for nursery sources for these trees. Since pecan trees come in two pollination types, you can help ensure cross-pollination by planting a mixture of varieties from the two categories. Jenkins and Gafford are type I varieties, while the others listed are all type II.

Pecan trees need to be planted 70 to 80 feet apart (unless you want to thin out some). Trees planted at 35-40 feet apart will need to be thinned in 15-20 years.

They'll do best in a deep, sandy loam soil that drains well. And there's no time like that before you plant to do soil testing, fertilizing, liming, deep digging or subsoiling. And don't forget to water once per week (if we don't get a good rain each week), mulch with an organic mulch layer (like pine needles), and keep the mowers and string line trimmers away. The best time to plant pecan trees is December and January.

So plant some pecans for your children and grandchildren — but leave behind scab-free pecans for them to remember you by. You'll be glad you did, I betcha.

Jerry A. Chenault is Urban Regional Extension Agent, New & Nontraditional Programs, in Lawrence County.

Subscribe for only 33¢ a day!

Leave feedback
on this or

Email This Page