Crabapple Cultivars Tested As Street Trees: Third Report
Henry D. Gerhold
Abstract: Through the Municipal Tree Restoration Program, cooperators planted 22 crabapple (Malus) cultivars in 31 communities for evaluation as street trees, typically comparing two in each community. Standardized measurements in years 1, 2, 3, 6, 9, and 12 revealed differences in height, crown width, and foliage health. These are useful for selecting the most appropriate cultivars for various site conditions. Only the tallest cultivars, ‘Spring Snow’ and ‘Red Barron’, have reached an average height of 6.5 to 6.7 m (21.5 to 22 ft) in 12 years, which is still below most electric distribution lines. Yearly growth patterns varied somewhat among locations and cultivars. The rate of height growth of most cultivars has been declining during years 9 to 12, and in many cases appears to be leveling off at heights between 4 and 6 m (13.2 and 19.8 ft). Red Jewel®, Sugar Tyme®, and Centurion® have narrower crowns, whereas others are still enlarging. Foliage health remained good to excellent throughout the summer on all but seven of the cultivars, and even these retained more than half of their leaves in good condition.
Keywords: Crabapple cultivars; Malus; performance testing; street tree evaluation.