By Dr. Aude Watrelot
Itasca grapes are a crossing made from Frontenac gris and MN1234 (which is a crossing from MN1095 and Seyval). Itasca is also known as MN1825 and was bred by Peter Hemstad at the University of Minnesota in 2002. This variety was selected and tested in 2009. Itasca, named after Itasca State Park, was introduced in 2016 and released in 2017, and has recently been introduced in Canada.
The grapevines of Itasca are very cold hardy and can resist temperatures down to -26 to -29 °F (-32 to -34 °C), but they do not tolerate excessive rain at harvest. This variety has an early bud break, and the berries tend to ripen early. Some years, the berries may turn pink although Itasca is still considered a white grape.
Itasca is very resistant to downy and powdery mildew, slightly susceptible to black rot on the leaves, and tolerant to foliar phylloxera. The vine is vigorous but manageable and does well on high cordon, but can also grow on a Vertical Shoot Positioning trellis system. The yield is about 5.29 kg/vine.
The harvest parameters are a degree Brix of 23-26, a titratable acidity (TA) between 7 and 12 g/L (this tends to be lower than other cold-hardy grapes such as Frontenac gris), and a pH of 3.2. The lower TA of Itasca white grapes makes this cultivar a suitable grape for dry wines.
The wines produced are not as fruity as La Crescent or Frontenac gris cultivars, but may have aroma such as pear, gooseberry, melon, starfruit, honey, or citrus (hints).
In the preliminary study carried out by the University of Minnesota on the effect of malolactic fermentation and extended skin contact on Itasca sensory perception, sensory panelists did not prefer the wine after MLF and with skin contact (Clark et al., 2017).
For in-depth information:
Clark, M., Hemstad, P., & Luby, J. (2017). “Itasca” Grapevine, a New Cold-hardy Hybrid for White Wine Production. Hortscience, 52(4), 649–651. https://doi.org/10.21273/HORTSCI11692-16.