MANHATTAN, Kan. – This summer’s yellowing and falling trees leaves are signs of stress, as are the browning leaves that stay in place.
Trees are reflecting the unusually warm, droughty weather that started last summer.
“Adequate water remains vital. With that, many trees can survive, if they also have enough stored energy reserves to make it through to next spring. Their twigs and buds will tell the story,” said Ward Upham, K-State Research and Extension horticulturist.
Typically, leaf loss isn’t serious if it simply results in general thinning, Upham said.
“Trees often set more leaves in spring than they can support during summer’s weather. So, they reduce leaf numbers,” he explained. “This summer’s thinning could look a little worrisome, though, unless you remember trees probably lost some roots over the past year.”
During extreme summers, certain trees (e.g., the hackberry) will drop all leaves and enter summer dormancy.
“Dormant trees should still have supple twigs and healthy buds,” Upham said. “If so, the effect on tree health is likely to be minor. The tree should leaf out normally next spring.
“However, if any section of the tree has brittle twigs and dead buds, that part, at least, is dead.”
When trees finally can’t keep up with their own moisture demands, they quickly die – seemingly overnight. Their leaves turn brown, but may remain attached to the tree.
“Again, though, twigs and buds are the most important clue to a tree’s health,” Upham said. “So long as buds are alive and twigs are supple, a tree has life. You should wait to see how it responds next spring.”
He recommends tree owners talk to their nearest Extension agent and/or consult K-State’s new factsheets about best watering practices for trees and shrubs. Those factsheets are on the Web at Watering Newly Planted and Young Trees and Shrubs and Watering Established Trees and Shrubs.
K-State Research and Extension is a short name for the Kansas State University Agricultural Experiment Station and Cooperative Extension Service, a program designed to generate and distribute useful knowledge for the well-being of Kansans. Supported by county, state, federal and private funds, the program has county Extension offices, experiment fields, area Extension offices and regional research centers statewide. Its headquarters is on the K-State campus, Manhattan.
Story by: Kathleen Wardkward@ksu.eduK-State Research & Extension News
Ward Upham is at 785-532-1438.