JUNE 25 EDITION OF "ASK THE ARBORIST"

Today, as promised, we are going to study in detail the Emerald Ash Borer (Agrilus planipennis).  The Emerald Ash Borer (EAB) is not native to North America and is believed to have entered our Western continent sometime in the 1990’s on a wooden shipping pallet. According to literature cited from “The U.S. Forest Service” positive identification was first detected in July 2002 in southeastern Michigan with EAB feeding on Ash trees (Fraxinus americana and Fraxinus pennsylvanica) both White Ash and Green Ash.  Since first detection the EAB has destroyed 50 – 100 million Ash trees in North America (including Canada) and threatens to kill most of the estimated 8.7 billion Ash trees in North America.  To date, the Emerald Ash Borer is considered one of the most destructive non-native insects in the United States.  This devastating insect has spread from Michigan, west to Colorado, south to Tennessee, and north to New Hampshire.  In July 2012 The Connect Agriculture Experiment Station (CAES) announced positive detection of EAB in Prospect, CT.   The EAB generally has a one year life cycle.  The adult EAB begins emerging in June or July. If you recall, from yesterdays discussion on EAB traps the CAES reported adult beetle activity last weekend in North Haven, CT.  The adult beetles live for about three weeks and can be present until mid August.  The adults are active during the day with warm sunny conditions; Most EAB adult beetles will seek refuge in bark crevices or foliage in inclement weather.  Adult EAB feed on Ash tree foliage where the harm to the tree is considered minimal.   Once females have mated they can lay 60 – 90 eggs during their lifetime.  Eggs are deposited individually in bark crevices, on branches or the trunk and hatch after 7 – 10 days.  Once hatched, the larva chews through the bark into the cambium layer of the tree.  The cambium layer (just below the bark) is often only one cell thick and is responsible for producing the phloem on the outside (later becomes part of the tree bark) and the xylem on the inside (becoming the sapwood).  Both the phloem and the xylem are responsible for transporting nutrients around the tree.  Once the Emerald Ash Borer larva chews into the cambium, phloem and xylem for feeding; the nutrient transport system is disrupted.  The tree is placed in severe decline and the result is the tree dies from starvation.  The EAB larva feed making winding “S” shaped galleries (see photos) that are filled with fine sawdust like frass.  Larva feeding is completed by autumn then overwinter in shallow excavated chambers in the sapwood or bark.  Pupation begins in April or May and the adult EAB exits the Ash leaving a familiar “D” shaped hole.  I attended a seminar August of 2012 with the U.S. Forest Service; and I must say in my over 25 years experience in Arboriculture this is by far the most destructive ruthless insect I have ever witnessed.  There is hope for the Ash trees! Thursday we will study in detail management options for Emerald Ash Borer.  Remember proper pest identification is necessary prior to any treatment program.  Contact your Yacko and Sons Tree Service staff Forester / Licensed Arborist for all your tree care concerns.  And remember Forester Jeff is always available to give your trees A FREE LOOK-UP FROM THE TRUNK-UP!  Jeff@yackoandsons.com  or   203-733-9219