Missouri's tree nut industry is evolving with the introduction of "Hickman," the first patented black walnut cultivar from the University of Missouri Center for Agroforestry.
A cultivar is a variety of plant that has been produced in cultivation through selective breeding. After 25 years of development, this new cultivar offers farmers an alternative to wild black walnuts with improved kernel quality and quicker production time.
The state has roughly 41 million black walnut trees that are five inches or larger in diameter, with 20% of all native range walnuts grown in Missouri, according to the Walnut Council. Additionally, 75% of native black walnut nuts that are purchased commercially are grown in the state, either on wild walnut trees or through cultivars.
Missouri Business Alert spoke with Ron Revord, interim director of the MU Center for Agroforestry and head of the Black Walnut Improvement Program, about this milestone for Missouri's tree nut industry and what it means for the state's agricultural industry. This conversation has been edited for length and clarity.
Missouri Business Alert: What is the significance of the "Hickman" walnut cultivar?
Ron Revord: The UMCA "Hickman" Walnut represents a significant milestone for Missouri's black walnut industry. It's the University of Missouri Center for Agroforestry's first patented black walnut cultivar, developed over 25 years and offering promising economic opportunities for the state's agricultural sector.
MBA: How long has this cultivar been in development?
RR: The work started with my predecessor (Dr. Mark Coggeshall) who joined the Center for Agroforestry. The first progeny, or breeding generation for our Eastern Black Walnut improvement program came from seed collected in 2002. Part of that breeding generation included the seedling that is now the cultivar Hickman that we're releasing.
MBA: What makes the Hickman cultivar superior to wild black walnuts?
RR: Hickman has a few characters that make it stand out from wild, but also make it stand out from other public domain cultivars. First and foremost is kernel mass, or percentage. The wild type kernel can range from like 6 to 14% where Hickman, depending upon the amount of water variability in a year, is somewhere between 30 and 40%.
Spur bearing is actually quite tightly correlated with time to flowering. In a wild type tree, that could be 10 to 15 years. In Hickman, it's been recorded as five years. And that's the earliest that Dr. Coggeshall has observed in the species.
MBA: Why is Missouri particularly well-suited for growing black walnuts?
RR: We have the better hardiness zone, but we also have the deep loess deposits ... really deep soils that formed post-glaciation. So they're fertile and they're fine, but they're also perched up in our river hills and rather well drained. These conditions make Missouri favorable not just for black walnuts, but for several other tree nuts as well.
MBA: What is the current state of the nut industry in Missouri?
RR: Missouri already has a modest pecan industry of about 10,000 acres. If over the next five or more years, we can get some acres of Eastern Black Walnut, that would be a major success. The presence of Hammons Product Company in Stockton, Missouri, which purchases large quantities of black walnuts from wild trees, provides a ready market for improved cultivars.
MBA: How significant is the market for black walnuts in Missouri?
RR: We're in a state that has the biggest buyer of Eastern black walnuts in the country. Even in light years, they'll buy all of the supply, which can be as little as 2 million pounds. In heavy crop years, Hammons has purchased up to 26 million pounds of in-shell, dehulled, dried nuts.
MBA: How will the Hickman cultivar impact the economics of black walnut farming?
RR: Hickman has the potential to really change the economics around Eastern Black Walnut orchards and return on investment. With its superior kernel quality and faster time to production (five years versus 10 to 15 years for wild trees), it offers farmers a more viable commercial option.
MBA: What are the Center for Agroforestry's goals for black walnut cultivation?
RR: One of our goals is to generate a regional tree nut industry for Missouri. We are really well-positioned to do this with our River Hills soils and favorable climate, especially in comparison to the broader Midwest. The Center aims to establish black walnut cultivars like Hickman as important building blocks for this industry.
MBA: Where can farmers obtain Hickman walnut trees?
RR: Forrest Keeling Nursery will be providing grafted plants of Hickman, with other licensed nurseries expected to follow. The Center for Agroforestry continues working to increase nursery supplies using micropropagation techniques.
