ash decline – Xtremehorticulture

Ash Decline (Disease). Or is it?

Leave a Comment / activated carbon charcoal, ash decline, damage, dicamba, sterilant / xtremehorticulture

Q. What might be happening to our ash trees? We noticed that a couple of our ash trees are not doing well at all. I did a quick google search yesterday and found an article you wrote about ash dieback. I’m hoping that’s not what is happening to our trees, but it does look like it. The only other thing that might have happened is that my husband put sterilant down on some rocks nearby last November. Now we are wondering if perhaps the sterilant made its way down to tree roots that may have been growing beneath the rocks? I believe he treated the whole area with the sterilant, and you can see where the tree trunk is located in relation to the rocks. If it is in fact a chemical injury to the trees, is there anything that can be done? Ash Decline (disease) or not? Ash Decline looks just like the trees are not getting enough water. You wont know until you water it (give it some extra water) for a few weeks and find out. Unless you want to pay a big plant pathology bill. A. I don’t think your ash tree has this particular disease. After looking at the pictures you sent, I think it was caused by the sterilant. It’s helpful if you can tell me the name of the sterilant used. Many sterilants are taken up by plant roots. The sterilant damage usually occurs on leaves and stems. On leaves, sometimes they “scorch” (their leaf margins will burn). This is what I think I see. In many cases the leaves turn yellow or become “bleached”. This is the type of “yellowing” I’m talking about. It is not “sterilant” yellowing but this is the color I am talking about. Tree roots watered by rainfall extend horizontally to about the length of their height. So, if you roughly (visually) lay the tree on its side and spin a circle with it, that roughly extends the length of their roots (with rainfall). Some pine trees I was given to spray with Dicamba, because we saw some dicamba issues on some pine trees when I worked for Utah State University as a Horticulturist. In the desert tree roots follow water. Wherever water is applied, that’s where you will find its roots if this area is under its canopy. I noticed a lawn under the tree. Did you kill a part of the lawn with sterilant? Many sterilants are taken up by plant roots but this sterilant can oftentimes be seen in the leaves. Dicamba was also used as a sterilant. This is what dicamba damage looks like on pine trees. Shout out to my friends in SLC Utah. If it is sterilant damage, you can try a couple of things. First try to wash it out. It may or may not work. Putting a lot of extra water in that area may flush the sterilant out. Just remember to give a day or so without water to give a chance for the roots to “breathe”. Roots need both air and water to survive. There is a chance that putting activated charcoal (expensive, activated carbon its called and is specific to the sterilant) may help but it depends on the sterilant used. When there is consistent rainfall, roots of trees extend all through the soil under its so-called “canopy”. Your ash tree grows in a lawn. Watering lawns is more even, regular, and consistent than rainfall. Ash trees do remarkably well in lawns. In my opinion that is their preferred way of getting water to the roots. Ash trees infected with ash decline are not getting enough water to the dying limbs. This disease plugs the water conducting vessels in tree limbs. As this disease slowly gets worse, more and more limbs begin dying because of a lack of water. The homeowner ends up removing the tree because it looks “ugly”. To see if your tree has this disease or not, give it some extra water once a week during the summer! An extra irrigation during the week tells you if the tree has this disease or not. If the tree does not improve in a few weeks with this extra irrigation, then assume the tree has the disease. The mistake made by most homeowners, in my opinion, is not removing the tree as soon as they decide one way or another. If you have confirmed this disease, then remove the tree as soon as possible. This tree can spread this disease to other ash trees!

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‘Bonita’ Ash and Ash Decline Disease

Leave a Comment / ash death, ash decline, dying / xtremehorticulture

Q. I planted a very large ‘Bonita’ ash tree this year and was worried about ash decline disease. This last May we noticed there were not as many leaves growing as we expected and many of the ones that were growing scorched and fell off. After 4 months of very good care to water, fertilize, and condition as told, the ‘Bonita’ ash tree does not look as we were told when we bought it. While it has grown taller, it had not filled in much. ‘Bonita’ Ash Tree recently planted. A. Ash Decline disease can be confused with a lack of water. It may also be confused with poor planting practices and leaving the ash out too long before planting. Possible ash decline disease. The only real way to say it is ash decline is to send a sample to a plant pathologist familiar with the disease. Nearly all ash trees are susceptible to ash decline disease, particularly if it has Arizona ash genetics in it. ‘Bonita’ ash does. So do ‘Modesto’, ‘Raywood’, ‘Rio Grande’, and other ash trees commonly sold in nurseries. That being said, this disease is usually not a problem on young ash trees as long as they are not stressed and there are no diseases present that might cause it to spread. Young ash trees are normally very strong and healthy. Disease Pressure The keys to resistance are “disease pressure”; how much of this disease is present on ash trees in your neighborhood and the “health” of your trees. The disease agent that causes ash decline is not terribly virulent. It is not like a disease such as fireblight which can be terribly destructive under the right conditions. If the ash trees in your nearby neighborhood don’t show any symptoms (branch or limb dieback) and kept healthy, then most likely the tree you planted will live disease free for many years to come. Give Them Water and Fertilizer and See if they Recover Make sure your tree are not water and fertilizer stressed. All ash trees are “mesic” in their water needs. Even desert ash trees, such as Arizona ash, grows near waterways. Like mulberry, all ash trees are dioecious; there are male trees and female trees. There is little difference in the health of a male vs. female ash tree. Ash tree surrounded by lawn and well fertilized and watered. They are mesic and can withstand a lawn. Ash trees can get big. Make sure they get enough water as they get bigger. Getting enough water is one key to having a thick and broad canopy and staying healthy. The irrigation under the tree should be enlarged every two to five years to compensate for their increase in size. Keep Ash Trees in Good Health The other important ingredient regarding canopy density and health are annual fertilizer applications. At least once a year and its canopy density, apply a fertilizer high in nitrogen, the first number on the fertilizer bag. Examples might include 16-6-8 or 16-16-16. Ash tree about 3/4 mature and surrounded by grass. They can get big. Their need for water is not as much as mulberry but close. Ash trees don’t care much for rock on top of the soil unless their roots are growing in a rich soil underneath it. Periodically rake any rock away from the trunk of the tree, enlarge the irrigation system, apply compost to the soil surface and fertilizer. The rock can be raked back the same day you are finished.

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Branch Die Back in Fantex Ash Tree

1 Comment / ash decline / xtremehorticulture

Q. I have three fantex ash trees. Every spring there are branches that don’t seem to bounce back from winter. They sometimes get the tufts like they are going to get leaves but never do. This winter was unusual and this year it seems I have more partial branches (my guess is last years growth portion) that have no leaves. Do I cut these off or not worry about them? My largest tree of the three could be a runner up for the game of thrones throne….ok not that spiky but worse than I’ve seen it and it’s close to being above my two-story house. REALLY don’t want to lose that tree. No pictures submitted A. The it’s a little difficult to say without seeing what’s going on but I lean towards a disease that we’ve had problems with an ash trees over the past 30 years in the Las Vegas Valley called ash decline. I am assuming that these leafless branches are dry and brittle. It is a slow, progressive disease that kills more and more in the canopy year after year. The trees struggle and don’t have a lot of new growth. It doesn’t seem to matter what you do to the tree, once they get this disease they eventually die over time. I have tried adding more water, more fertilizer and it doesn’t seem to make any difference. Personally, I have noted that trees growing in rock landscapes seem to be coming down with this disease problem sooner than trees not going in rock landscapes. Eventually you’ll have to remove it and plant something else in its place. Ash decline Same tree. Ash decline. Same tree, the trunk. This ash tree was growing in a lawn. You can look at some of my posts on ash decline https://xtremehorticulture.blogspot.com/2018/01/dieback-of-mature-fan-tex-ash.html https://xtremehorticulture.blogspot.com/2017/10/limbs-dying-in-20-year-old-arizona-ash.html https://xtremehorticulture.blogspot.com/2015/06/ash-dieback-or-ash-decline-they-both.html

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Unknown Tree With Branch Dieback Not Ash

Leave a Comment / ash decline, Japanese privet, Texas privet, wax leaf privet, waxleaf privet / xtremehorticulture

Q. I have a tree that appears to be dying but I don’t know what it is. I was reading your article about the disease on ash trees and tried to access the pictures of ash trees but couldn’t find them. I believe the tree is about 15 years old. Readers tree A. Thank you for sending me pictures of your tree. I can tell you it is definitely not an ash tree. It was difficult to identify from the pictures but from the close-up of the leaves I think it is Japanese privet, sometimes called wax leaf privet. This is a tree or sometimes grown as a shrub commonly planted in southern Nevada. If this is wax leaf privet you should see clusters of white flowers followed by black berries about the size of blueberries in the same clusters. Privet with leaf drop and twiggy dieback due to irrigation They frequently have the same problem here which is dieback of small branches which makes them look very “twiggy”. I posted a picture of this plant growing in southern Nevada on my blog that shows this branch dieback and leaf drop I am talking about. This plant doesn’t like our desert environment or drip irrigation very much. It definitely does not like rock mulch. They prefer growing in a much lusher environment. The only time I really see them looking good is when they’re surrounded by a lawn that receives a lot of water. You might try putting bedding plants that require watering water every couple of days and surround the tree with wood mulch or a very lush lawn. They do great in East Texas all the way back to the Carolinas but do not look all that well in landscapes located in the dry or desert West. See these links in this blog http://xtremehorticulture.blogspot.com/2014/08/privet-dieback-due-to-irrigation.html http://xtremehorticulture.blogspot.com/2011/07/q.html

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Don’t Confuse Leaf Drop with Ash Decline

Leave a Comment / ash decline, ash tree branches dying, ash tree dying / xtremehorticulture

Q. I have an ash tree which appears to be dying. I am considering taking it out but would like to have someone look at it before I do. A. The usual problem here with ash trees has been a disease called ash decline or ash dieback. I have posted questions I received regarding this problem on ash trees along with pictures of what it looks like and what to do if you have it. Ash decline Send some pictures to me of the tree showing the problem when you see the problem. I need close-ups of the leaves as well as a picture of the entire tree. Look at the pictures I have posted here or on my blog to confirm it. This disease is quite easy to identify from pictures. If you are certain the tree has this disease it should be removed. There is no cure for it. This email was confirmed as ash decline and the tree removed.

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Ash Dieback or Ash Decline? They Both Kill the Tree.

5 Comments / ash decline, ash diseases, What is causing dead limbs in my ash tree, why is my ash dying / xtremehorticulture

Q. I have a 23-year-old ash on a drip system with 10, five gallon per hour emitters watered twice per week for 30 minutes. It is located on a southern exposure and planted in a rock mulch. It has a drip system. The tree has begun to lose leaves and limbs are dying. Is the tree just old or am I doing something wrong? Ash tree showing die back. This is not the tree mentioned here. A. You are watering this tree about 50 gallons a week if all the emitters are working properly. As hot weather is upon us, I don’t believe that this will be enough water to support this tree. That is probably enough emitters for that tree if they are spaced 2 to 3 feet apart under the canopy of the tree. If the emitters are grouped too closely together much of that water will be wasted. You want to wet about half the area under the canopy of the tree each time you water to a depth of 18 to 24 inches. Instead of just placing emitters under the canopy of the tree, an alternative method is to place other plants under the canopy that require water as well. I believe there are several advantages to the tree in doing this. Ash decline May 1st is usually the critical time when we increase the frequency of applied water from once a week (beginning the first week of February) to twice a week. Unfortunately a couple of the ash tree varieties have been developing this kind of problem since before I arrived in the Valley in 1984. I remember during the mid-1980s I was called out to look at some very large Modesto ash trees near downtown North Las Vegas. These ash trees were on city property and surrounded by turfgrass or lawns that were in very good condition. The trees had leaves which were curling up and dying as well as branch dieback. Ash decline will kill the branches of ash trees. If the trees are not pruned and maintained properly these trees will become a safety hazard. This ash tree limb from an ash tree with ash decline broke from the tree and hit this house during a mild wind storm. The plant pathologist for the state of Nevada and I sent samples to pathology labs looking for some answers. It first came back as a disease called ash yellows but it was later found that this diagnosis was incorrect by the same laboratory. The landscape contractor I was working with, Nanu Tomiyasu, had tried fertilizers, increasing the amount of water to the tree even though it was in a lawn and nothing seemed to help. He was desperate for answers. Dieback occurring on fantex ash Fast forward now to 2015. This disease on ash, first found on Modesto ash, has been found on other ash varieties like Arizona ash that have been introduced into the Valley since that time. Plant pathologist from the University of Arizona has acknowledged this disease and written about it http://ag.arizona.edu/pubs/diseases/az1124/ calling it Arizona Ash Decline and the University of California has termed it Ash Dieback. There are some assumptions about this disease but everyone seems to agree that it is not controllable and eventually the tree will become a hazard and should be removed as the disease progresses and limbs die more and more. Increasing the fertilizer and water the plant receives will not help. I have no evidence for this but I assume that this disease is transmitted by insects such as the Apache cicada which is common here or whiteflies. Putting ash trees in less stressful environments such as lawns or supplying enough water to the tree roots, seems to help prolong its health. I am telling people that this tree will be short-lived in our environment, 10 to 20 years, until this problem is resolved. They should not be confused with dieback of limbs when older, established ash trees are no longer in lawns but part of a landscape retrofit to desert landscaping. In my opinion, this will shorten the trees life. Before the tree becomes a hazard, please remove it. If this is ash decline there is nothing you can do to save it.

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