Extension notes is written by K-State Extension of Harvey County extension agents Scott Eckert, Susan Jackson and Ryan Flaming. They focus on horticulture and agriculture.
We know that fall is a great time to plant new trees in the landscape. Sometimes we need to protect the investment from the elements in the early years. Many young, smooth, thin-barked trees such as honey locusts, fruit trees, ashes, oaks, maples, lindens and willows are susceptible to sunscald and bark cracks. Sunscald normally develops on the south or southwest side of the tree during late winter. Sunny, warm winter days may heat the bark to relatively high temperatures. Research done in Georgia has shown that the southwest side of the trunk of a peach tree can be 40 degrees warmer than shaded bark.
This warming action can cause a loss of cold hardiness of the bark tissue resulting in cells becoming active. These cells then become susceptible to lethal freezing when the temperature drops at night. The damaged bark tissue becomes sunken and discolored in late spring. Damaged bark will eventually crack and slough off. Trees will often recover but will need some TLC (especially watering during dry weather). Applying tree wrap from the ground to the start of the first branches can protect recently planted trees. This should be done in October to November.