Michael Polozola

In the heart of Louisiana, the quest to discover superior low-input cultivars of pecan from native pecan trees is underway. This endeavor, driven by dedicated research and trials conducted by the LSU AgCenter, is crucial for the survival and prosperity of the pecan industry in the state. By exploring the rich history and current state of the industry, the importance of finding new low-input cultivars will become evident.

Challenges in the Pecan Industry

The Louisiana pecan industry has long been a cornerstone of the state's agricultural landscape. However, disease, pests and economic pressures have made it increasingly difficult for traditional cultivars to thrive. One of the most destructive threats is pecan scab, a fungal disease caused by Fusicladium effusum. It primarily affects leaves, nuts and young shoots, leading to black lesions that can merge and cause significant damage. Pecan scab thrives in warm, humid conditions and can severely reduce both the yield and quality of pecans, making it the primary limitation to pecan production.

Managing pecan scab in cultivars with no-to-low resistance requires regular fungicide applications, which can be costly. In response, the industry has shifted toward low-input production practices that rely upon scab-resistant cultivars, which are more sustainable and economically viable.

Under this strategy, the variety Elliot has reigned supreme. Although it is an older pecan variety, Elliot has maintained its scab resistance for more than a century. It produces smaller, oil-rich kernels known for their great taste and good kernel fill, allowing it to command a premium in the Louisiana market.

Unfortunately, Elliot has developed one significant weakness. When not treated with fungicides, it is not scab but Gnomonia leaf spot that poses the greatest threat. This disease takes hold late in the season and causes early defoliation. While occasional early leaf drop is not a major issue, repeated yearly defoliation causes a problem known as alternate bearing — producing fruit every other year — to occur more than usual and produces lower quality pecans. While it is not unusual for Elliot to alternate bear on a two-year cycle, this emerging issue is causing some trees to enter a three- or even four-year yield cycle.

The Search for New Cultivars

To ensure the industry's future, it is essential to identify and cultivate new pecan varieties that combine high yield, quality and disease resistance with minimal input requirements. Auburn University has made significant efforts in this area, introducing low-input selections such as Amling, Gafford, McMillian and Syrup Mill. Additionally, Kanza and Lakota from the U.S. Department of Agriculture pecan breeding program have shown potential.

While these varieties can perform well across the state, south Louisiana presents a unique microclimate with high disease pressure. Very little work has been done to search this germplasm — the living genetic resources, such as seeds or tissue — for new selections. Fortunately, a few passionate individuals in the Louisiana Pecan Growers Association have taken on the task.

This work also holds great potential for homeowners. With the development of pecan trees that are resilient and productive with minimal maintenance, homeowners can enjoy the benefits of growing pecans without the need for intensive management. These low-input varieties are ideal for backyard orchards, providing a sustainable and rewarding option for those interested in cultivating pecans at home.

As part of the LSU AgCenter Extension efforts, collaboration with passionate growers has yielded great results. Some USDA and Auburn selections have shown both scab resistance and productivity. In an exciting development, Louisiana native selections with potential have been identified though caution is necessary. These selections can often fall victim to the “yard tree effect,” where a tree performs well in isolation within its unique microclimate but underperforms when replicated in orchard conditions.

Various individuals have trialed their unique native finds, but most have fallen victim to the yard tree effect. Two promising selections have emerged from this quest: Manda and Woodman. Both are native selections from Pointe Coupee Parish, identified through collaborative efforts involving the LSU AgCenter and local growers.

Manda: The Precocious Cultivar

Manda has proven to be very precocious, meaning it enters production early in its life cycle. These can be thought of as “lifetime trees” because an older person can plant one and live to see it produce a crop. Remarkably, Manda has yielded up to 5 pounds of pecans within just four years of planting.

Manda has shown tolerance to pecan scab. Though it may have a light infection in years of high disease pressure, this does not significantly reduce its yield. The only issue observed is that Manda can be too enthusiastic in its yielding potential, setting a large crop that can cause limb breakage in some years. Nevertheless, it produces nice, average-sized pecans with moderate oil content, making them a good choice for various uses.

Woodman: The Resilient Cultivar

Woodman has shown great potential for low-input settings. One of its many strengths is that it holds its leaves late in the season, avoiding the early defoliation that Elliot is prone to. This difference is dramatically evident when the two cultivars are grown side by side, with Elliot often looking quite bare next to a Woodman still full of foliage.

There are multiple implications of this trait. By holding its leaves longer, Woodman does not exhibit significant alternate bearing. While it may still have slightly off years after a heavy one, these are much less likely to occur, resulting in consistent yields year to year. The extra carbohydrate reserves it accumulates from holding its leaves later in the season also contribute to faster growth compared to Elliot. Woodman trees will grow larger more quickly with fewer inputs than Elliot trees in the same environment. Additionally, Woodman naturally grows with excellent branch angles, contributing to its status as a healthy, long-lived tree resistant to limb breakage and weather injury.

Woodman also demonstrates great scab resistance, further enhancing its suitability for low-input settings. It produces nice, average-sized pecans with moderate oil content, making them a reliable choice for growers.

Securing the Future of Louisiana's Pecan Industry

The quest to uncover Louisiana's hidden pecan gems is not just about preserving the past but also about securing the future of the state's pecan industry. By identifying and cultivating low-input cultivars like Manda and Woodman, growers can ensure sustainable and economically viable production. While Manda's precocity allows for early production, Woodman's consistent yields and robust growth make it a reliable choice for long-term cultivation. These cultivars show potential for resilience and productivity, making them valuable additions to Louisiana's pecan repertoire.

To ensure these new selections can be made available for purchase, collaboration with the nursery industry in Forest Hill has been crucial. Forest Hill, located in Rapides Parish, is a key hub for Louisiana's nursery industry. The area is renowned for its excellent water quality, favorable climate and long growing season, all of which are ideal for long-term plant growth. This makes Forest Hill an important center for nurseries that supply a wide variety of plants, including pecan trees. By working closely with nurseries, efforts are being made by AgCenter agents to propagate and distribute these promising cultivars, making them accessible to both commercial growers and homeowners. This partnership is vital for the widespread adoption of these new varieties and the overall success of the pecan industry in Louisiana.

These efforts not only benefit commercial growers but also offer exciting opportunities for homeowners to enjoy the rewards of pecan cultivation. As research and collaboration continue, the future looks promising for Louisiana's pecan industry, with resilient and productive cultivars leading the way.

Michael Polozola, the LSU AgCenter Extension state fruit and nut specialist, is stationed at the AgCenter Dean Lee Research and Extension Center in Alexandria.

This article appears in the spring 2025 edition of Louisiana Agriculture.

Woodman pecans grow in a Pointe Coupee Parish orchard in November 2024. Photo by Kyle Peveto

Woodman pecans grow in a Pointe Coupee Parish orchard in November 2024. Photo by Kyle Peveto

Pecans that are not quite ready for picking grow from a tree in a Pointe Coupee Parish orchard in November 2024. Photo by Kyle Peveto

In the foreground stands an Elliot pecan tree, which loses its leaves earlier than Woodman pecan trees standing in the background. Photo by Kyle Peveto