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Arizona Walnut | Juglans major

Scientific Name

Juglans major

Common Name

Arizona Walnut, Arizona Black Walnut

Photo of Juglans major.

Photo: M. Ritter, W. Mark, J. Reimer courtesy of SelecTree

Tree Description

Juglans major, Arizona walnut, is a medium to large deciduous tree. It has a spreading crown of pinnate foliage and produces edible nuts.

Tree Size
Medium
Height at Maturity
30ft–60ft
Growth Rate
24 inches/year
Foliage Type
Deciduous
Sun Exposure
Sun
Part-Shade
Water Needs
Low Water
Medium Water
Potential Issues

Mildly susceptible to Thousand Cankers disease; likely susceptible to mistletoe; susceptible to aphids, sooty mold. Moderate root damage potential. Allergy health hazard.

Field Trial Monitoring Results

Poor potential utility as an urban tree based on evaluation of 11 trees, slightly unhealthy crown, 73% survival, moderate growth rate. Herbivory and leaf discoloration found on a few individuals. Several field trial plants were lost at transplant, roots seem to be sensitive.

Propagation Results

We started both fresh seed and 4 month old seed with both receiving a 2 day bleach soak then 120 day cold stratification in moist perlite in plastic bag in refrigerator. Both had equally good germination with the same treatment. Seedlings are fast-growing with a nice form.