Green Horizons

From chestnuts to paw paws, the 96th annual meeting of the Northern Nut Growers Association (NNGA) spanned the gamut of nut and related fruit crops. More than 150 NNGA members from across the country attended the meeting held July 31-Aug. 3 at Central College in Pella, Iowa, an event that has become an excellent opportunity for researchers, hobbyists and commercial growers to exchange ideas and learn about advances and new markets in the industry.

Participants attend a discussion about the advantages of managing a black walnut orchard using grafted trees at Billie and Geri Hanson’s orchard near Centerville, Iowa, just north of the Missouri border.

A board meeting and the traditional show-and-tell event kicked off the meeting on July 31. Monday included several educational talks and sessions, the majority featuring chestnuts. Dennis Fulbright, professor, Department of Plant Pathology, Michigan State University, presented a series of images from his chestnut sabbatical to Italy. Fulbright explained the overwhelming popularity, familiarity and interest in chestnuts in Italy, including a series of chestnut festivals during the month of October and chestnut posters, displays and themed items appearing in nearly every store window and street corner. "Chestnuts in the fall in Italy are as common as seeing a fall leaf or a pumpkin in the United States," he said.

Sandra Anagnostakis, Agricultural Scientist at The Connecticut Agricultural Experiment Station (CAES), presented a talk on her work in studying the nutritional factors of chestnuts that affect storage and taste. Research includes evaluating which crosses result in a higher protein and oil content, as well as the effects of a pollinizer on these factors. She is studying crosses based on linoleic and oleic acid levels in the nutmeat, because higher oleic acid has been reported to provide enhanced flavor and sweetness and low linoleic acid to improve storage.

Greg Miller, owner of Empire Chestnut Company, discussed the advantages and disadvantages of planting chestnut seedlings versus grafted trees. Problems Miller cited with grafted seedlings include graft failure, variable growth and difficulty in transplanting. Advantages to planting grafted trees include a more significant level of early production. Seedling orchards are viable only for Chinese chestnuts; other species do not have a high enough proportion of good seedlings. Challenges to planting seedling chestnut trees include genetic variation, a longer preproductive period, and greater difficulty to maintain as small trees. However, Miller described seedlings as less expensive to plant and manage than grafted trees and as a "more forgiving" tree in terms of grower error. He recommends overplanting then thinning out seedling trees if necessary, spacing the trees from 30 to 40 feet and being patient with production speed. For grafted trees, Miller suggests planting trees 15-40 feet, pruning or thinning at close spacings, using intensive cultural inputs, such as weed control, fertilizer, and irrigation. Topworking established seedlings may be more successful than transplanting grafted trees.

Ken Hunt, post-doctoral fellow, University of Missouri-Columbia Center for Agroforestry (UMCA), described Chinese chestnut cultivar performance in Missouri at the University of Missouri Horticulture and Agroforestry Research Center (HARC). The major program focus is screening cultivars for commercial use. There are three field studies, a repository with 55 cultivars (2 trees of each type); a cultivar trial, with 12 cultivars (5 trees of each type); and a nut production orchard, with 3 cultivars (8 sixtree replications). Factors tested include nut yield, nut size, date of nut maturity, timing of bud break, flowering and tree growth habit.

The annual auction offers a range of hardwood and nut-themed items for sale, serving as a fundraiser for NNGA research programs.

Results of the Center’s recent chestnut market analysis and report were presented by Mike Gold, associate director, UMCA. The Center’s long term objective is to create a thriving domestic chestnut industry, focusing its efforts on three key areas: national market research, production techniques/orchard management and increasing consumer demand and awareness. The outcome of this effort will be an active program that reaches out to potential producers and establishes a multi-million dollar chestnut industry within the state of Missouri and surrounding states. Through national market surveys sent to producers, and businesses active in the U.S. chestnut market the Center reported that the U.S. chestnut industry is in its infancy. The majority of producers have been in business less than 10 years, many just beginning commercial production. Current production volume is low, less than 1.5 million pounds nationwide. Demand exceeds supply, and grower prices often exceed $3.50 a pound. Barriers to success in the chestnut business include the lack of information for producers, retailers and consumers, a 5 to 10 year time lag to get a return on investment, and a shortage of available chestnut nursery stock of commercial cultivars.

Monday afternoon’s talks offered a variety of additional nut themes, including insect pests on hickory and walnut, the restoration of butternut in Southern forests, nitrogen fertilization for hazelnuts and the potential of paw paws in the upper Midwest.

Nut forums allowed NNGA members to openly discuss challenges, successes and experiences with various crops in a small group setting. Attendees could attend forums on seven different types of nuts, in addition to persimmon and paw paw: black walnut, chestnut, hazel nut, heartnut, hickory and pecan. At the chestnut forum, discussion topics included types of sites best suited for chestnut, pollination, temperature effects, marketing, organic production, graft failure and root stock development.

The annual auction highlighted Monday evening’s events, offering a range of hardwood or nut-themed items for sale, many the result of members’ agricultural or craft endeavors - including seedling nut trees, homemade nut-themed baked items, handcarved wooden kitchen items, honey and wines. Proceeds from the annual auction support nut tree research.

Tuesday morning’s talks featured pecan and black walnut, with presentations by researchers including Bill Reid, associate professor, Kansas State University, who spoke about Northern pecan cultivars and the phenology of early ripening across the northern Midwest (primarily Kansas, Missouri and Illinois). Reid described an increasing interest in growing pecan orchards in these states and presented an order of ripening for varieties used in this region.

Dave Brauer, Agricultural Research Service (ARS) agronomist/ research leader, presented a talk on the growth potential and establishment of black walnut varieties in North Central Tennessee, a potential replacement crop for tobacco farmers. Brauer emphasized the importance of positioning plantings properly in the landscape to control flooding.

An update on the Black Walnut Cultivar Performance Project was presented by Billie Hanson of Ben’s Black Walnuts, Centerville, Iowa. The goal of the project, funded in part by NNGA, Farm Bureau and others, is to help determine which cultivars are best suited for six regions of Iowa. Production and nut quality data may be available soon, as well as data collection on frost sensitivity and ripening.

Mark Coggeshall, Tree Improvement Specialist, UMCA, shared the progress of the black walnut breeding program and rootstock evaluation underway at the Center’s research farm. The Center’s black walnut research program is designed to uncover new and improved usages for black walnut in agroforestry practices. Coggeshall is currently working on a project for identifying specific species exactly and accurately, using DNA fingerprinting. Due to propagation or data collection errors, many black walnut cultivars have been determined to be “problematic,” and the DNA fingerprinting project will help confirm the cultivars’ original identities. Bud break, leaf-out date, fruit shape and husk thickness are some of the characteristics under evaluation.

Tigernut (from Africa) and vegetation management for tree growth were also included in Tuesday morning’s presentation topics. Key topics for Tuesday afternoon’s discussions centered around potential markets for commercial nuts and nut products.

Attendees examine part of the equipment that Billie and Geri Hanson use to remove the husk, float and wash black walnut nuts in a 1000 ppm chlorine solution before moving clean nuts to a drying bin.

Larry Godsey, Research Associate/Economist, UMCA, presented a financial model for determining the economic feasibility of establishing a nut tree crop, including a tree growth model for use as an income projection tool. Tom Wahl, of Red Fern Farm, Wapello, Iowa, offered insights on the differences between producing nuts commercially or as a hobby crop. Wahl’s recommendations included having a mission statement, business plan, and market research in place prior to beginning a commercial operation.

Wednesday’s field tours brought participants to the black walnut orchards and production facility of Ben’s Black Walnuts, a prototype commercial black walnut operation in Centerville, Iowa. A project planting for the Iowa Black Walnut Cultivar Performance Project was viewed at the orchard of Merlyn Carter, also in Iowa.

For more information, visit www.nutgrowing.org.