Tree with leaf loss

Asked July 25, 2016, 3:45 PM EDT

Our front yard tree has excessive leaf loss. Similar trees in our development have some loss, but ours is the most extreme. The problem has occurred in prior years, but this year is the most severe. See pictures attached. Is this a disease, lack of water/nutrients? The tree seems healthy otherwise. Anything we can do to prevent or cure this?

Washington County Oregon trees and shrubs drought

1 Response

I apologize for the delay. I responded yesterday but the gremlins interfered with the transmission!

Based on the images you attached, my best long-distance guess is that the tree is unable to absorb adequate water to supply its needs through our dry months. The less than normal rainfall is compounded by the reflected heat from concrete on 3 sides of the tree. Unfortunately, linden trees are not drought-tolerant. They require regular irrigation through our dry months, enough to moisten the entire root zone every several weeks.

Numerous trees, both those in landscapes and untended areas, are failing this year due to several consecutive years of low rainfall compounded by the unusual heat of 2015. It seems that a record number of trees are declining this year in spite of the spring's abundant rainfall. In many instances, it arrived too late.

Given that your tree has repeated this sort of behavior for several years, the tree may be declining. After decline symptoms appear – off-color leaves, substantial leaf drop, and tip die-back – it may be challenging, perhaps impossible, to stop and/or reverse the process.

The close-up views also reveal small white flecks on some leaves. If the tree is dropping sticky stuff, aphids may also be present and adding further stress. Washing them off with a harsh water spray, repeated every several days, could potentially assist the tree.

Consider contacting a Certified Arborist for an onsite visit to evaluate the tree's status. (We suggest Certified Arborists because they are trained in tree care, must pass an exam, and must accumulate mandated continuing education.)

You can locate Certified Arborists in the Yellow Pages, online or in a phone book, under the heading of Trees or Tree care. Or search with your zip code at www.treesaregood.org. Tree care companies with such a person will include that information in their ads, either as a brief statement or as a small rectangular logo stating “Certified Arborist.” When you contact each company, ask if they have a fee to take a look – some do, some don’t.

“Decline in trees and shrubs” may provide some insights - http://www.mortonarb.org/trees-plants/tree-and-plant-advice/horticulture-care/decline-trees-and-shrubs as will “Linden aphids” - http://hortsense.cahnrs.wsu.edu/Search/MainMenuWithFactSheet.aspx?CategoryId=1&SubCatId=5&PlantDefId=173&ProblemId=833