Hackberry aphid problem

The Hackberry trees in this community are an asset for shade, cooling, and to create a better environment. Unfortunately, there is a new problem that is coming around called the Hackberry Aphid that is making these trees more of a nuisance. My name is Blair Glenn, I am an ISA certified Arborist. This is a fairly recent problem that is erupted just in the last few years. The leaves are covered with these little white insects. There is a little closer view, see if we can zoom in a little closer still. Little out of focus, but the tree is covered with thousands and thousands of these little sucking insects that cause the tree to drip. Now, the problem is if you park your car underneath one of these trees, it becomes a sticky mess. The road becomes sticky, you walk on the surface of the asphalt and your shoes stick to the street. This was not a problem a few years ago. This is a problem that has erupted in the last three to five years. So what do you do about it? In constraint communities, external spraying of pesticides and toxins is often frowned upon, so it is a difficult thing to deal with in a conventional manner. I have recommended using high pressure hoses and pressure washers. If you are careful, you do not want a tight harsh bin, but you want a big fan, and you can washed off the leaves, and it does a fairly good job of cleaning up the mess, but controlling these insects is going to be ongoing battle. Some people have resorted to putting injections in to the trees and allowing the tree to systematically try to control it. I have found that this is ineffective. If you go to the UC Davis website, you will that this is a procedure that actually causes harm to the trees. Continued applications of these injections and inserting these toxins in to the trunk of the tree causes the trees to develop trunk cankers and areas of decline. Continuing it annually will cause these areas to actually merge and cause large areas of die back on the trunk. There is a close up of last year’s injection, and you can se that it is cracking, and there is something oozing. Somebody is identifying this so they put a little bit of white paint to locate the most recent injection from last year’s application. And this is from a few months ago and you can there is excessive weeping and oozing from the most recent injections in the tree. And finally on this last photograph, this trunk has had numerous injections over the years which are all leading to trunk problems there is. Some of these injections are joining and some of them are creating areas of dieback and bark decay. So, if you like to know more about the Hackberry Aphid, Google it and you will find a great report of the UC Davis website. One again my name is Blair Glenn. I am an ISA certified Arborist.