Hazelnut Status Report              J. F. Kelsey - - - 2019 Feb 27

The European hazel Corylus avellana is the common hazel of Europe, western Asia, and is the commercial hazelnut species worldwide.  The smaller American hazel species, Corylus Americana, grows in eastern North America and is not a commercial species.  C. Americana hosts the fungal disease Eastern Filbert Blight “EFB” to which it is immune.  The commercial C. avellana species, however, is sensitive to the EFB.  The only area of commercial hazelnut production in North America is near the Pacific coast, well outside the native range of the C. Americana, the EFB host.      

Despite quarantines the EFB appeared in the western commercial region sometime in the mid 1900s and slowly began decimating commercial hazel orchards.  Growers fought back with chemicals and an   aggressive breeding program at Oregon State University. 

https://catalog.extension.oregonstate.edu/em9073/html

Tree breeding is a slow process and chemicals slowed the disease while researchers developed new resistant varieties.   One resistant European variety (Gassaway) was discovered, which became the anchor of the OSU (sorry Buckeyes and Cowboys) breeding program.  Several new varieties were tested and released by OSU, mostly with the Gassaway resistance gene.   Western EFB infected orchards were, and continue to be, ripped out and replanted with new OSU’s releases.   Also, OSU continues to develop new releases with further EFB resistance and other improved characteristics.  

It doesn’t take a genius to light on the idea “If EFB is whipped, why not an eastern hazelnut industry?”  Of course there were some minor obstacles like: no agricultural plan, no knowledge base, unknown pest and climate pressures, and no market infrastructure.   Eastern hobbyist and nurseries began planting the OSU material and two major eastern breeding programs were started. 

The Upper Midwest Hazelnut Development Initiative is a breeding, a development, and an educational program.     https://www.midwesthazelnuts.org/   Besides the EFB “elephant-in-the-room”, the upper Midwest is a bit north of C. avellana’s comfort zone.  The breeding approach was to start with a multitude of avellana/Americana hybrids.  The program has about 150 cooperators in Wisconsin, Minnesota, and Iowa who have around 80,000 hybrid plants growing for evaluation.  The plants are old enough for early production results, and a few promising prospects have been identified and are being clonal tested.   Meanwhile agricultural and processing methods are being developed for the hybrid plants, which are smaller than their C. avellana ancestor. 

A major breeding program was begun at Rutgers University in New Jersey in 1996.  Due to the continuing quarantine, the western growing region only has one strain of the EFB fungus, while the East has several strains.  OSU varieties, with the Gassaway resistance gene, are having mixed results in the East, depending on the locale and the variety.  The Rutgers program began by collecting all strains of the EFB fungus to thoroughly expose new plants. 

The Rutgers research farms abound with the C. Americana EFB host to present the highest EFB pressure.  Meanwhile, C. avellana material has been collected from earlier American researchers, Europe, and western Asia to be exposed at the Rutgers farms.  The goal is to find other resistances and to achieve higher EFB resistance (and even full immunity) by means of multiple resistance genes.  The Rutgers program has planted and EFB inoculated around 80,000 plants, mostly from hand pollinated crosses between promising C. avellana individuals.  The Rutgers variety evaluation process is meticulous and guarded.   The best clonal material is out to cooperative growers for further exposure.  When the Rutgers varieties are finally named and released, we can be assured of some very good cultivars for eastern growers.

http://agproducts.rutgers.edu/hazelnuts/

Concerning eastern markets, the Ferrero Rocher Company, who makes Nutella and those wonderful hazelnut chocolates, has built a factory in Ontario.   With Ferrero Rocher’s encouragement, Ontario hazelnut growers have organized with the goal of supplying the Ferrero Rocher demand.

http://www.ontariohazelnuts.com/

Also, an Ontario hazelnut research program is underway at Guelph University.

https://www.uoguelph.ca/oac/news/opportunity-grows-ontario-hazelnut-trees

The major breeding programs, along with the Arbor Day Foundation, work together with a cooperative atmosphere.  There is a lot of grower interest in the best varieties.  The eastern breeding programs are unable to meet the demand for clones of their best plants.  These are research sites, not commercial nurseries.  Even at nurseries, traditional propagation methods are too slow to meet the demand for clonal plants.  They are always “sold out”.  Tissue culture companies are being involved.  Hopefully an adequate supply of the best cultivars will soon become available, and eastern orchardist can begin learning the peculiarities of growing hazelnuts.