20-053 — Provisional Recommendations And

Factsheet

#20-053 | AGDEX 240 | AUGUST 2020

Provisional Recommendations and Descriptions of Hazelnut Varieties in Ontario T. Leuty

INTRODUCTION potential market uses and yield and sensitivity to The Ontario hazelnut industry is currently in a state winter injury (hardiness zone). of early commercial development. Hazelnut cultivars are being evaluated as potential crop cultivars and Hazelnuts are self‑incompatible. This means that pollen source cultivars, based on their ability to a hazelnut plant will not pollenize its own female tolerate minimum winter temperatures, spring frost flowers or pollenize female flowers of other and manage native diseases, mainly Eastern filbert hazelnut plants within the same variety. Hazelnut blight (EFB) and bacterial blight. Maturing orchards varieties must cross-pollenize with other compatible have begun to produce an annual hazelnut crop. varieties in order to set and grow a nut crop. It is Kernels are being evaluated for quality attributes recommended that growers provide three to five and for various market uses including fresh, different compatible pollen source varieties for each confectionary and other value-added products. crop cultivar to ensure successful pollen transfer and optimize crop yield. The timing of pollen Table 1 provides provisional hazelnut variety release is also a factor. Male catkin flowers should recommendations for Ontario with revised release pollen when the female crop flowers are tolerance/susceptibility to Eastern filbert blight, open and receptive.

Table 1. Provisional hazelnut cultivar recommendations (crop and pollen source) for Ontario Cultivar Eastern filbert Catkin Fresh market and Hardiness and source blight survival confectionary Yield Zone Pollen-compatible varieties Gene moderate tolerance good fresh market very good Zone 5–7 Slate, Norfolk, Jefferson Jefferson susceptible okay both okay Zone 7 Gene, Gamma, Yamhill Yamhill susceptible poor both okay Zone 7 Gamma, Santiam, Jefferson Chelsea moderate tolerance good both good Zone 5–7 Gamma, Yamhill, Gene Norfolk moderate tolerance good both good Zone 5–7 Gene, Jefferson, Slate Gamma susceptible fair both good Zone 7 Jefferson, Yamhill, Santiam, Theta Slate moderate tolerance fair fresh market good Zone 5–7 Gene, Norfolk, Lewis Alex moderate tolerance good both good Zone 5–7 TBD Source: Cultivar evaluations conducted by the University of Guelph, Horticultural Experiment Station, Simcoe, Ontario.

Ministry of Agriculture, Food and Rural Affairs Before deciding on which hazelnut varieties to Consult with knowledgeable tree nursery providers, plant, growers are advised to investigate the kernel experienced growers or an OMAFRA crop specialist characteristics of each variety and the varietal if additional information is required. preferences of the markets they want to supply. Fresh markets, such as farm gate sales or farm Since development of the information in Table 1, markets, generally accept good quality nuts of additional new and existing hazelnut varieties have all hazelnut varieties. Confectionary companies, been released or imported for evaluation in Ontario processors and makers of value-added hazelnut yet have not undergone formal comparative testing. products may have specific requirements that are found only in some varieties and not in others. For example, a confectionary company may only purchase specific hazelnut varieties that have round, medium-size kernels and exact expectations of flavour. Prevention of spoilage mould in kernels after harvest and during storage is a priority to maintain quality and top market value.

Contact the Ontario Hazelnut Association for information on how to participate in variety trials.

2 Table 2, the Compatibility Chart, presents a list In the Compatibility Chart, hazelnut crop varieties of current hazelnut varieties that can be planted (left column) that share similar expressed alleles in on farms and evaluated by growers. Table 2 also pollen source varieties (top row) are incompatible provides guidelines on selecting compatible pollen and will not cross-pollenize. Asterisks indicate the source varieties to design commercial orchards, alleles that are expressed, and are incompatible optimize nut set and crop yield, enable uniform with the same allele number. ripening of varietal blocks and the option of mechanized harvest.

Table 2. Ontario hazelnut compatibility chart, developed in cooperation with Oregon State University and Rutgers University LEGEND: X = incompatible c = compatible * = expressed alleles Pollen source variety — Pollen (male) parent Gamma Yamhill Jefferson Theta Lewis Santiam Gene Slate Norfolk Chelsea Linda Cheryl Carmela Matt Aldara Frank Marion Dawn Raritan Monmouth Hunterdon Somerset

2 8 1 5 3 3 15 1 12 1 14 10 25 11 25 14 14 15 3 1 3 3 Alleles 10 26 15 8 15 25 20 12 13 27 12

Oregon State University varieties: Zone 6b or 7 Gamma *2 *10 X c c c c c c c c c c X c c c c c c c c c c Yamhill *8 *26 c X c c X c c c c c c c c c c c c c c c c c Jefferson *1 3 c c X c c c c X c X c c c c c c c c c X c c Theta *5 *15 c c c X c X X c c c c c c c c c c X c c c c Lewis *3 *8 c X c c X X c c c c c c c c c c c c X c X X Santiam *3 *15 c c c X X X X c c c c c c c c c c X X c X X New York varieties: Zones 5–7 Gene *15 23 c c c X c X X c c c c c c c c c c X c c c c Slate *1 23 c c X c c c c X c X c c c c c c c c c X c c Canadian varieties: Zones 5–7 Norfolk *12 25 c c c c c c c c X c c X c c c c c c c X c c Chelsea *1 *20 c c X c c c c X c X c c c c c c c c c X c c Linda *14 23 c c c c c c c c c c X c c c c X X c c c c c Cheryl *10 *12 X c c c c c c c X c c X c c c c c c c X c c Carmela 23 *25 c c c c c c c c X c c c X c X c c c c c c c Matt 11 13 c c c c c c c c c c c c c X c c c c c c c c Crop variety — Female parent Crop variety — Female Aldara 25 27 c c c c c c c c X c c c X c X c c c c c c c Frank 14 c c c c c c c c c c X c c c c X X c c c c c Marion *14 25 c c c c c c c c c c X c c c c X X c c c c c Dawn *15 27 c c c X c X X c c c c c c c c c c X c c c c Rutgers University varieties: Zone 7 Raritan *3 22 c c c c X X c c c c c c c c c c c c X c X X Monmouth *1 *12 c c X c c c c X X X c X c c c c c c c X c c Hunterdon 1 *3 c c c c X X c c c c c c c c c c c c X c X X Somerset *3 10 c c c c X X c c c c c c c c c c c c X c X X

3 VARIETY DESCRIPTIONS OF HAZELNUTS IN ‘Jefferson.’ Zone 7. Released by Oregon State ONTARIO University in 2009 for the in-shell market. The nuts Oregon State University varieties of ‘Jefferson’ are large, well filled (3.2–4.2 g) and ‘Gamma.’ Zone 6b–7. Released by Oregon State have 45% kernels by weight. Raw kernels have University in 2002. Released as a pollenizer but a moderate-to-heavy amount of fibre on their also suitable as a main variety. The trees set many pellicles. ‘Jefferson’ blanches only moderately catkins, and pollen is shed in mid-season. The well. Kernel quality is suitable for many end pollen shedding period is short, therefore ‘Gamma’ uses, although they are larger than desired by should not be the sole pollenizer in an orchard. It the chocolate and bakery industry. It has high is a suitable pollenizer for ‘Lewis’ and ‘Barcelona,’ yield, attractive nuts, kernels and good kernel but sheds pollen too early for ‘Clark.’ The average quality. About 80% of the nuts fall free of the nut weight is about 2.5 g, and it blanches poorly. husk at maturity. The variety matures at or up Kernel percentage by weight is 52%. ‘Gamma’ has to 3 days later than ‘Barcelona.’ ‘Jefferson’ has a 12% blank and brown-stained nuts. The frequency low frequency of mouldy kernels. Pollen is shed of mouldy kernels is very low (1%). The variety is in mid-season, but female receptivity is very susceptible to Ontario strains of Eastern filbert late. Pollenizers that shed pollen very late are blight and resistant to big bud mite. It is very needed. In Oregon, one-third ‘Eta’ and two-thirds suitable for the processing industry. ‘Theta’ is suggested. ‘Yamhill’ pollen is effective on early emerging female flowers and should be ‘Yamhill.’ Zone 6b–7. Yamhill was developed and incorporated into an orchard at double the normal evaluated by the hazelnut breeding program at planting density. ‘Jefferson’ is susceptible to Ontario Oregon State University, Corvallis, Oregon, and strains of Eastern filbert blight, is tolerant of big bud was released in January 2008. Trees of ‘Yamhill’ mite and is susceptible to bacterial blight. are susceptible to Ontario strains of Eastern filbert blight (EFB). Trees of ‘Yamhill’ are smaller but very ‘Santiam.’ Zone 7. Developed by Oregon State productive, and nuts mature at the same time as University, Corvallis, Oregon, and released in 2005. those of ‘Santiam’ and ‘Gamma.’ Good marketable Nuts of ‘Santiam’ are suited for the kernel market, nut yields, and kernels have few defects, although however are too small for the in-shell market. The they are small and best suited for the fresh kernel nut weight ranges from 2.0–2.1 g, while kernel market. Tendency toward flatter branch angles weight ranges from 1.0–1.1 g. Kernel percentage allows good light penetration without excessive by weight ranges from 48%–52% with moderate sunburn to the foliage, husks or bark. blanching ability. ‘Santiam’ has a low percentage of blank and brown-stained nuts but has a higher occurrence of mouldy kernels in Ontario. Nuts mature, and more than 90% fall free of the husk by the end of September. In most years, harvest of ‘Santiam’ is completed before the beginning of ‘Barcelona’ harvest. The variety has not shown a biennial bearing tendency.

‘Santiam’ sheds pollen early mid-season and has short-to-intermediate pollen shed. Female bloom occurs late-to-very late in the season, so it requires a very late-shedding pollenizer variety. ‘Santiam’ produces a large amount of pollen and has potential as a pollenizer. Rooting can be poor; young trees can die in the field. Trees of ‘Santiam’ are susceptible to Eastern filbert blight in Ontario and have intermediate tolerance to big bud mite.

4 ‘Lewis.’ Zone 7. Developed by Oregon State ‘Slate.’ Zone 6–7. Slate is an exceptional annual University, Corvallis, Oregon, and released in nut producer of medium-to-large size nuts on a January 1997. The variety nut weight ranges medium-size tree. It can be a pollenizer for Zone 7 from 2.7–3.0 g, while kernel weight ranges from trees, but it would be better matched as a main 1.2–1.4 g. It has 6% blank and brown-stained nuts crop nut producer in Zone 6. It came from the and up to 8% of mouldy kernels. The kernel quality same breeding project as ‘Gene’ and was a cross of is very good, with good flavour, texture, round ‘Rush’ x ‘Barcelona.’ It is tolerant to Eastern filbert shape with moderate blanching ability. Raw kernels blight but is susceptible to bud mite. The nuts drop have very little attached fibre. Nut clusters contain about the same time as ‘Gene.’ Slate’s alleles are 1 3–4 nuts. Nuts are free husking and ready to harvest and 23, with 1 being expressed in the pollen. Both 5–7 days earlier than ‘Barcelona.’ ‘Lewis’ has not cultivars can be harvested together, since the nuts exhibited a biennial bearing habit. are very similar.

Female flowers bloom at the same time as Canadian Varieties ‘Barcelona.’ Pollenizers suggested in Oregon are ‘Cheryl.’ Zone 5–7. This is a later selection from ‘Tonda di Giffoni’ and ‘Hall’s Giant,’ while other the same breeding program that created ‘Gene.’ pollenizer options are available in Ontario. Plant It is a cross of ‘Rush’ x ‘Kentish Cob.’ It is a equal numbers of each pollenizer to pollinate heavy‑producing cultivar with alleles 10 and 12. the early and late-appearing flowers. ‘Lewis’ is Both alleles are expressed in the pollen. It cannot susceptible to Ontario strains of Eastern filbert be used as a pollenizer for ‘Gamma’ where it shares blight and is moderately susceptible to big bud mite. allele 10. It is blight-tolerant but susceptible to bud mite. The nuts are medium-to-large size and similar ‘Epsilon.’ Zone 7. Released by Oregon State to ‘Gene’ in nut size, shape and ripening time. It is University in 2002. Average nut weight is 2.6 g. productive enough to be a main crop selection. It Kernel percentage by weight is 49%, and it blanches yields over 39% kernel. poorly. ‘Epsilon’ has 7% blank and brown-stained nuts. The frequency of mouldy kernels has averaged ‘Linda.’ Zone 5–7. This is also a later selection from 8%, which would be excessive for a main crop the same breeding program as ‘Gene.’ It is a heavy variety but should not be a problem for a pollenizer. producer similar to ‘Gene’ in nut shape and ripening The trees set many catkins, and abundant pollen time. It has alleles 14 and 23, with 14 expressed in is shed late in the season. The duration of pollen the pollen. Since only 14 is expressed in the pollen shed is intermediate to long. Susceptible to Eastern and not the 23, it can be a pollenizer for ‘Gene’ and filbert blight in Ontario and highly resistant to big ‘Slate.’ It is productive enough to be a main crop bud mite. tree. It is blight-tolerant but susceptible to bud mite.

New York varieties ‘Carmela.’ Zone 5–7. This is a Grimo Nut Nursery ‘Gene.’ Zone 5–7. Developed in the breeding selection from seed collected from the Geneva program at the New York Agricultural Experiment Experimental Farm breeding project. The tree is Station in Geneva, New York, also known as large like ‘Gene.’ The nuts are large, oval in shape ‘Geneva.’ A very productive, annual-bearing and well filled. This nut is favoured by growers for selection that produces a large spreading tree up its size and flavour. The alleles are 23 and 25. It is to 4 m tall. Nuts are medium-to-large size, pointed alternate bearing but is suitable as a late pollenizer and well filled. Nuts ripen in mid-season, and most variety. The nuts are late ripening so it can be drop free from the husk. Kernels are round with paired with early-ripening cultivars to maintain no clinging fibre. The alleles are 15 and 23, with 15 nut separation at harvest. It is blight-tolerant but being expressed in the pollen. Gene is tolerant to susceptible to bud mite. Eastern filbert blight, is winter hardy and susceptible to big bud mite.

5 ‘Alex.’ Zone 6–7. Selected by Grimo Nut Nursery ‘Kiara.’ Zone 5–7. Is a recent introduction from of Niagara-on-the-Lake, Ontario. The tree is large the Grimo Nut Nursery in Niagara-on-the-Lake, and moderately productive. The nuts are medium Ontario. It is an open-pollenized seedling of a hybrid size, oval and well filled. The nuts ripen at the end produced at Morden Station by Les Kerr who was of September, and most of them drop free from the the director at the time. He used a Saskatchewan husk. The kernels are oval with no clinging fibre. It American hazel with pollen from George Slate at is a moderately productive and alternate-bearing the Geneva Experimental Farm in New York. ‘Kiara’ variety. The variety is winter hardy, is tolerant to is a small tree planted in 2001, measuring 2.5 m Eastern filbert blight and moderately resistant to across and about 2 m high (9 ft x 7 ft). Rows of big bud mite. The pollen compatibility with other ‘Kiara’ should be 5 m x 3.6 m (16 ft x 10 ft) apart to varieties is unknown. maximize production. It is the heaviest producer of the Saskatchewan group. The nuts are medium size ‘Matt.’ Zone 6–7. Selected by Grimo Nut Nursery and average 37% kernel. The alleles have not been of Niagara-on-the-Lake, Ontario. Matt is a sister identified yet, but its sister trees have a 14 allele, tree of ‘Alex,’ a seedling of Faroka. Faroka is a so this may be one of its alleles too. It would not be Turkish tree hazel x European cross made by the wise to use ‘Kiara’ as a pollenizer for any of these Gellatly Nut Nursery of Westbank, British Columbia. trees with the same parent background, or them It is alternate-bearing, and as a result it is only for it. The best pollenizers would be those from moderately productive. The nuts are larger than the Asian/Quebec source. It is blight-tolerant but ‘Alex’ with no clinging fibre. It is a good pollenizer susceptible to bud mite. with alleles 11 and 13 and able to pollinize any of our selections. It is blight-tolerant and resistant to ‘Frank.’ Zone 5–7. Is a sibling of ‘Kiara.’ It was bud mite. planted in 2001. ‘Frank’ is the widest tree in this group at 4 m (13 ft) and about 2 m (7 ft) tall. Rows ‘Dermis.’ Zone 5–7. Mr. Skinner was a novice should be 4 m x 5 m (13 ft x 16 ft) apart. The nuts breeder in Manitoba that produced ‘Skinner,’ from are medium size, round, free of fibre and 40% a cross of his native hazel with European pollen. kernel. It is annually productive and suitable as a Dermis is a seedling selection of ‘Skinner’ by the main cultivar. It has only one allele identified as Grimo Nut Nursery in Niagara-on-the-Lake, Ontario. 14 so it must be matched with trees other than This large tree is very productive, producing siblings. It is a good late pollenizer with a long medium-size round nuts with very little fibre. It receptive period. It is blight-tolerant but susceptible would be a suitable mid-to-late season pollenizer. to bud mite. Identification of the alleles has not been completed yet, it can cross-pollinate with ‘Frank,’ ‘Marion,’ ‘Marion.’ Zone 5–7. Is a sister tree to ‘Kiara’ from ‘Dawn,’ ‘Gamma,’ ‘Linda,’ ‘Cheryl’ and ‘Gene.’ The the same parent source. It was planted in 2001 and nuts are late ripening so it can be paired with is a small tree like ‘Kiara.’ It is a moderate producer early-ripening cultivars to maintain nut separation of medium-size, round, fibre-free nuts and 37% at harvest. It is blight-tolerant but susceptible to kernel. In a 3-year period, it averaged 2.3 kg (5 lb) bud mite. of nuts. ‘Marion’ is a favoured cold hardy tree in Ontario by growers. It has alleles 14 and 25 with 14 expressed in the pollen. It is a late pollenizer with a long receptive period to ensure a crop. The tree is 3 m (9 ft) across at 17 years of age, so it can be planted at 3 m x 5 m (13 ft x 16 ft). It is blight‑susceptible in Wisconsin but so far not in Ontario. It is not resistant to bud mite.

6 ‘Joanne’™. Zone 5–7. Is a sister tree to ‘Kiara’ and Canadian hybrid varieties of Corylus of similar size and spread. It was planted in 2001. heterophylla (Asian hazelnuts). The nuts are medium size, round, free of fibre and ‘Aldara.’ Zone 5–7. Is an open-pollenized 40% kernel. It is similar in production to ‘Marion.’ Asian/Quebec seedling selected by the Grimo Nut It has alleles 2 and 14 with the pollen expressed Nursery in Niagara-on-the-Lake, Ontario. It, along in 14. It is not compatible with ‘Linda,’ or any of with ‘Dawn,’ are the two best selections at the the Saskatchewan hybrids. It is blight-susceptible Grimo orchard of 60 seedlings from the Corylus in Wisconsin but so far not in Ontario. It is not heterophylla hybrid test planting. It is still an resistant to bud mite. Grimo Nursery considers it a outstanding tree for hardiness, production, annual suitable late-season pollenizer. bearing, nut shape, nut qualities and vigour. The nut is medium size, slightly larger than ‘Dawn.’ ‘Norfolk.’ Zone 5b–7. Norfolk was selected in The original tree grew to a height of about 3.5 m. Ontario by Martin Hodgson of Courtland, Ontario, The nuts drop in early September. Its alleles are 25 from a batch of germinated seedling trees for its and 27. The percent kernel for 2018 crop year was tolerance to cold and moderate survival to EFB. between 43% and 44%. The ‘Aldara’ trees were Norfolk has medium vigour, upright and spreading planted in 2008 in heavy clay soil and so at 10 years growth, weak suckering. Kernels are medium size old, they are still not mature size. They average 3 m and weight, are long and cylindrical having 2–3 nuts (10 ft) across, so spacing will be good at 3.6 m (12 ft) per cluster. The alleles are 12 and 25. The 12 allele in the row. It is blight-tolerant but susceptible to is expressed. Pollen is released early season, female bud mite. ‘Aldara’ has a long pollenizing period from flowers open mid-to-late season. Catkins are winter mid-to-late season. hardy and have good annual production of pollen. ‘Andrew’™. Zone 5–7. Is another sibling to ‘Aldara.’ ‘Chelsea.’ Zone 5b–7. Martin Hodgson of Courtland, It was selected for its blight tolerance and nut Ontario, selected Chelsea along with Norfolk from qualities. The nut is round, slightly larger than a large batch of seedling trees. Chelsea has similar ‘Aldara,’ well filled and free of fibre. It tends to be growth and kernel characteristics as Norfolk and alternate bearing so is not recommended as a main is considered an excellent annual source of pollen. crop cultivar but as a mid-season pollenizer instead. The alleles are 1 and 20, both alleles are expressed. It is susceptible to bud mite. The alleles have not Nuts of Chelsea and Norfolk ripen at the same time been identified yet. and can be harvested together. ‘Dawn.’ Zone 5–7. This selection is in the Asian/Quebec genetic group from the Grimo Nut Nursery in Niagara-on-the-Lake, Ontario. The parent was described as a Corylus heterophylla seedling tree, but this parent lacked some of the typical characteristics. Thus, Grimo’s believe it is a hybrid, possibly crossed with a C. Americana. ‘Dawn’ is very productive with small-to-medium nuts that are 47% kernel. In a 3-year study when this was a 10-year-old tree, it averaged 5.2 kg (11.5 lb) of nuts. It has alleles 15 and 27, with 15 expressed in the pollen. ‘Dawn’ was planted in 2008 and at 10 years of age is 3.6 m (12 ft) in diameter and about 3 m (10 ft) tall. Rows of this tree should be planted at 5 m x 3.6 m (16 ft x 12 ft). It has a long pollenizing period from early-to-mid-season.

7 ‘Northern Blais.’ Zone 5–7. Corylus heterophylla weight, good blanching, nuts fall free of husk hybrid seedlings purchased from the Grimo Nut at maturity. Nursery and planted in Quebec by Jacques Blais from Joly, Quebec, in Zone 4b. In the fall of 2011, Mr. Blais ‘Somerset.’ Zone 7. Is a compact tree, slightly dug up the Ortet and brought it to the Grimo Nut spreading, high yielding, early-to-mid-season bloom. Nursery in Niagara-on-the-Lake, Ontario, where it Free of EFB due to single gene EFB resistance from was planted in the orchard for further evaluation ‘Ratoli.’ S alleles 3, 10. Kernels are round, most are in 2012. It had a good crop every year since it was 12–13 mm in diameter, kernel weight average 1.14 g, planted, even though it was susceptible to bud mite. kernel percent average 54.9%. Blanching is average. The tree has shown very good tolerance to blight. Nuts fall free of husk at maturity, early maturing. The nut is similar to ‘Aldara’ in size and shape but a lower percent kernel. It has proven hardiness for CONCLUSION Quebec. The alleles are to be determined. Tree nursery operators who are attentive to changing varietal preferences among growers Rutgers University, Landmark™ Hazelnut and have the capacity to quickly propagate large series. quantities of quality trees, will be necessary to For information, contactFoggy Bottom Tree Farm, a establish a healthy hazelnut industry in Ontario. licenced U.S. propagator. A reliable supply of nursery stock that is guaranteed with true-to-name varietal identity will be necessary ‘Hunterdon.’ Zone 7. Is a vigorous upright tree, high to maintain grower confidence, as it exists with yield, early-to-mid-season bloom. Very tolerant to tree fruit industries. The hazelnut diseases, Eastern EFB (few cankers form under high disease pressure). filbert blight and bacterial blight, can be effectively Quantitative EFB resistance S alleles 1, 3. Kernels are managed by adopting production practices of round, slightly oblong, most are 12–14 mm diameter. pruning out and burning infected wood and Kernel weight average 1.23 g, kernel percent average applying protective sprays, similar to fruit orchard 45.9%, excellent blanching and flavour. Nuts fall free practices. Varieties that are currently being grown of the husk at maturity, very early maturing. in orchards are surviving Ontario’s winter cold and sporadic spring frosts in orchard regions that ‘Monmouth.’ Zone 7. Is moderately vigorous, slightly are moderated by the Great Lakes. Crop yields in spreading and high-yielding. Early-to-mid‑season maturing hazelnut orchards are increasing each bloom. Very high level of tolerance to EFB (few cankers season, indicating potential for a reliable annual form under high disease pressure, most cankers lack profit for growers, that will overcome the cost stromata). Quantitative EFB resistance S alleles 1, 12. of orchard establishment and annual production Kernels are round, 12–14 mm diameter, average kernel costs. Early experiences with fresh market sales weight 1.2 g, kernel-to-shell dry weight 51.8%, very are showing there is significant demand for locally good blanching, nuts fall free from husk at maturity. grown hazelnuts at competitive prices.

‘Raritan.’ Zone 7. Is a vigorous upright tree with high yield, has a very high level of tolerance to EFB (very This factsheet was authored by Todd Leuty, Tree Nut few cankers form, cankers lack spore‑producing Horticulture and Forestry Specialist, OMAFRA, Guelph. stromata). Quantitative EFB resistance S alleles The ministry thanks Dr. John Zandstra, University of 3, 22. Kernels are round, 12–14 mm in diameter, Guelph, Linda and Ernie Grimo, Grimo Nut Nursery, average weight 1.14 g, 48% kernel-to-shell dry Barb Yates, Ferrero Canada, Dr. Tom Molnar, Rutgers University.

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