Indiana’s drought, winter took a toll on conifers and other evergreens

Yews and other conifers were hit hard by the drought of 2010. (C) Jo Ellen Meyers Sharp

S.C. from Indianapolis writes about evergreens that have “turned completely brown and died over the winter” at the building where she works. “I have noticed the same thing happening throughout the city. All types of evergreens seem affected. Do you have any idea what is going on?”

Almost all of the yews (Taxus), arborvitae (Thuja), pine (Pinus), junipers (Juniperus) and other needle conifers have been damaged or killed by last year’s drought. Broadleaf evergreens, such as Rhododendron and holly (Ilex), also, might look crispy brown instead of lush green.

Homeowners, property managers and others almost always pay more attention to watering the lawns during drought than they do trees and shrubs.

Evergreens are the most susceptible to winter damage because they retain their needles or leaves throughout winter, a trait that gives them their common name. Because their foliage is exposed to the elements year-round, evergreens, especially, need to go into winter well saturated.

If conifers are damaged or dead only on one side, that’s the area that most likely is driest, exposed to winds or is closest to a building, sidewalk, street or other hard surfaces. A hardscape’s microclimate intensifies heat and light, which can contribute to plant damage. Also, the soil strip under the eaves of houses and other buildings is about the driest in the landscape.

The bad news is that the brown evergreens will not recover and will have to be replaced. Yews are about the only evergreen that will re-grow green branches after being cut back, but it will take a long time.

We won’t know for a few weeks how flowering and other deciduous trees and shrubs coped with the drought. Fewer or smaller flowers usually indicate a struggle. The lesson — make sure all trees and shrubs get adequate water before winter sets in.