Tuesday, April 16, 2013

Evidence of Anthracnose Infection

Anthracnose diseases of hardwood trees are widespread throughout the Eastern United States. The most common symptom of these diseases is dead areas or blotches on the leaves. Because of the brown and black, scorched appearance of the leaves, the diseases are sometimes called leaf blight.
For more information on the basics of anthracnose see our previous posts here and here.

Today we'll focus on symptoms on infected leaves. These symptoms range from tiny dead spots to large circular or irregular dead blotches, depending on the tree species. Dead areas are black, brown, or purple. On sycamore and maple (below), infected areas are often found along the veins and midrib of the leaf. The dead areas may merge until the whole leaf dies.












Infection in the early spring may turn the leaves black so that they resemble leaves damaged by frost (below). If they are not killed by the fungi, young leaves may become distorted by the unequal growth in healthy and infected parts. Distorted leaves are common on oaks.



If you are so unfortunate as to have severely infected trees, then it is quite possible that they may lose their leaves. But if defoliation occurs in spring or early summer, a tree will usually produce a second crop of leaves (see photo below).

Symptoms on most trees are confined to the leaves. On sycamores and oaks, however, the fungi may also affect twigs, buds, and shoots.



This severely infected tree is refoliating.


Symptoms: Sycamores, Oaks



On sycamores, there are four distinct stages of anthracnose: twig blight, bud blight, shoot blight, and leaf blight. These stages often overlap, as shown below; any one or more stages can be seen during the spring or summer when weather conditions are just right for the development of the disease. Above you'll see Anthracnose infection along the vein of an oak leaf.

On oaks in the white oak group, symptoms are similar to those on sycamore, but less severe.

Twig blight. Twig blight occurs in the spring before the leaves emerge. After the tips of 1-year-old twigs are killed, small, black fruiting bodies of the fungus soon break through the bark of the dead twigs (below).  Fungal fruiting bodies break through the bark of a dead sycamore twig. Later, cankers-dead areas in the bark-may appear on older branches below the dead twigs. These cankers girdle and kill the branches.





Bud blight. Bud blight occurs at the same time as twig blight. When cankers girdle the individual buds, the buds die before the bud caps begin to break.

Shoot blight. During the shoot blight stage, emerging shoots and new immature leaves suddenly die.

Leaf blight. In the leaf blight stage, both young and mature leaves are infected with spores produced on twigs and branch cankers. Necrotic spots or blotches are found on the leaves, and dark-brown fruiting bodies of the fungus are found on diseased leaf tissue.

Now that you know about the symptoms and different kinds of blight, it is important to understand how to prevent the spread of the blight. You can control the spread of blight. Stay tuned to find out more.

This was brought to you by Trees "R" Us, Inc. A full service tree care company serving the Chicago suburbs, including Chicago's North Shore, and the north and northwest suburbs of Chicago.

Thursday, April 11, 2013

Leaf blight

Anthracnose diseases is also often called leaf blight. It is a disease for mainly hardwood trees and is widespread throughout the Eastern part of the United States. The most common symptom of these diseases is dead areas or blotches on the leaves. The nickname of leaf blight was created because of the brown and black, scorched appearance of the leaves.

The symptoms vary somewhat, depending on the host. Under certain conditions, the whole leaf dies and falls prematurely. On some tree species, the diseases may also damage twigs, shoots, buds, and fruits. Repeated defoliation reduces growth, weakens the tree, and increases its susceptibility to attack by other pests and to winter injury.

These diseases are caused by several closely related fungi, plants that reproduce by means of spores - which are the fungal equivalent of seeds. Spores spread the disease when moved by wind, rain, or mechanical means from one host to another.

Which trees are most susceptible to leaf blight?

Anthracnose fungi attack numerous hardwood species, including ash, basswood, birch, catalpa, elm, hickory, horsechestnut, London planetree, maple, oak, sycamore, tuliptree, and walnut.

Although anthracnose diseases have been found wherever these trees grow, not all hardwoods are equally affected. The diseases are particularly severe on American sycamore, white oak and other oaks in the white oak group, and black walnut. Sometimes, these species are almost completely defoliated; and on black walnut, nut production is affected. Infections are frequently found on other oak species, including scarlet, black, red, and southern red oaks; but the red oaks appear to be less susceptible than the white oaks. Pin oak, swamp chestnut oak, bur oak, and London planetree are only occasionally infected by the fungi. So if you are looking for a tree that is likely to escape leaf blight, these varieties are a good choice.

Remember to contact your local tree care specialist for containment, treatment and preventative measures for leaf blight.  Those readers local to the Chicago's North Shore and its surrounding suburbs, be sure to contact Trees "R" Us, Inc. for assistance with leaf blight or planting your new trees.

For more springtime tree care tips see our last post.

Tuesday, April 9, 2013

Spring Tree Care Tip

If you have trees that are susceptible to certain fungal problems, such as anthracnose, removing leaf and needle debris will help reduce the chance for issues later on.

Anthracnose diseases are especially prevalent in the hardwood trees particularly throughout the Eastern United States. Dead areas or blotches on the leaves are the most common symptom and tell tale sign of Anthracnose. Because of the brown and black, scorched appearance of the leaves, the diseases are also referred to as leaf blight.

The symptoms vary somewhat, depending on the host. Under certain conditions, the whole leaf dies and falls prematurely. On some tree species, the diseases may also damage twigs, shoots, buds, and fruits. Repeated defoliation reduces growth, weakens the tree, and increases its susceptibility to attack by other pests and to winter injury.

These diseases are caused by several closely related fungi, plants that reproduce by means of spores - the fungal equivalent of seeds. Spores spread the disease when moved by wind, rain, or mechanical means from one host to another.

It is hard to contain because of how easily the spores spread, but it can be done. Your local tree service with be able to assess the extent of the Anthracnose and provide you with a plan of action. If you are local to the Chicago Suburban area, especially the North suburbs of Chicago, Trees "R" Us, Inc. will provide you with advice on how to control, treat and even prevent future outbreaks of Anthracnose. Check out Trees "R" Us, Inc. at www.treesrusinc.com or call us at 847-912-9069.

Stay tuned for more information on Anthracnose is the coming posts.

Saturday, April 6, 2013

Dealing with Flood Injury, Now What?

If you've been following along, you know that we've been discussing flood injury to trees. As our last post on this series, today we'll discuss what to do when your trees have been adversely affected by flood injury.

Make sure to take close look at your trees and look for signs of flood injury. Once you confirm that your trees are suffering from flood injury, it is time to look at how the soil is draining. Unfortunately, there aren't very many short term solutions to this problem other than improving drainage. Whenever you choose to make changes to the drainage, you need to consider not only the tree that is sitting in a flooded area, but also the surrounding plants. Consider how the change in drainage will affect them too. Drainage will affect all area plants and landscaping, so make your drainage choices wisely. For advice on drainage issues, contact your local tree service. Tree care companies, such as Trees "R" Us, Inc. in the Chicago area, deal with drainage issues and other tree-care-related issues on a daily basis. They'll have the right answers for you and can do the work for you so you don't have to.

The best prevention for flood injury is a simple one however. It is to avoid planting flood-intolerant trees in areas that are frequently flooded. There are a variety of wetland trees and shrubs that can be planted instead. Another thing to consider is to avoid creating problems for flood-tolerant plants by providing drainage for intolerant plants.

For more advice on spring damage to trees, contact your local arborist. Here at Trees "R" Us, Inc., we have certified arborists ready to tackle issues such as flood damage. Our arborists are highly qualified with training and experience so you can rest assured that your trees and landscape will receive the right care by the right company and for the right price! So, if you are local to the north shore of Chicago or any of the other Chicago suburbs, contact Trees "R" Us, Inc. for your tree care needs. 

847-913-9069

Thursday, April 4, 2013

Tell Tale Signs of Flood Injury

A tree's health can really be affected adversely by excess water. Whether it is from a flood or a watering hose, pay attention to the amount of water the soil around your tree is absorbing.

It is labeled flood injury, but it is not just about how your trees will react to a flood. Read about flood injury in our last post here.

If you suspect that your tree may be harmed from flood injury, here’s how find out for sure. These are a few simple tell tale signs when you look for flood injury.

Flood injury is usually expressed through changes in the foliage. One symptom in particular, chlorosis, is commonly caused by flood injuries. Chlorosis is the yellowing of leaves caused by a decrease in the amount of chlorophyll (green pigment) in the leaves. This symptom can look like a symptom of a disease but is often caused by non-disease problems, such as excessive water.

A professional arborist can determine if chlorosis is caused by a pest or some other site factor, many of which can be controlled, or by water damage. A call to your local tree service that has certified arborist will be helpful. Trees "R" Us, Inc., a Chicago-area tree service, has several certified Arborists on staff ready to assess problems such as this.

Another symptom to look for is root dieback. When flood conditions are prolonged you'll notice anywhere from a little to excessive root dieback. During root dieback, soil is so saturated that there is not enough oxygen available to the tree roots. Without the proper balance of oxygen and carbon dioxide, roots can’t survive. Ironically, eventually the tree is not able to absorb adequate moisture, despite the flood condition. The tree will exhibit symptoms similar to leaf scorch, where a tree’s leaves turn brown and die due to a lack of moisture in the leaves. The symptoms usually start at the top of the tree or on the ends of branches, and spread throughout the entire crown. The symptoms are often more severe on the side of the tree facing the prevailing winds.

Symptoms of flood injury, in the order that they develop on the foliage, are:

1. slight wilting or drooping of the foliage;

2. a yellowing and browning (necrosis) of leaf edges;

3. browning in the center of the leaf.

So, now you've noticed that your trees have been affected by flood injury. Are your trees done for? Should you replant them? Should you deprive them of water until the soil dries out? Find out what is the best plan for trees aversely affected by flood injury in our next post. Stay tuned for what to do to correct flood injury.

Tuesday, April 2, 2013

Spring Floods Can Harm Your Trees

Did you ever think that your trees could drown? It's true.  Too much water can leave trees sitting in soil saturated with water. If the spring brings large amounts of rain, your trees are a risk of drowning. 

Too much water at the base of a tree can cause a myriad problems. Educating yourself about tree care and knowing where to seek assistance can help trees survive the spring thaw. Too much water can be as bad for trees as too little water. While some trees are suited to survive occasional floods, most are not. In addition, as a tree becomes older, its ability to adapt to abrupt environmental changes decreases. It is when spring water levels recede that most will begin to notice problems with their trees.

Trees must maintain a proper water balance. Although most trees can withstand moisture conditions from very dry to very wet for short periods of time, continued extremes can cause serious problems, depending on the tree species.

Some species – such as some oaks, pines and junipers – have adapted to survive drier conditions. Trees that grow along rivers (such as willows, poplars, cottonwoods and sycamores) and trees that grow in or around swamps and ponds (such as red maples, gums and pond cypress) have adapted to grow in wet conditions. 

Flood injury occurs when soil becomes unusually saturated with water. And, just because it is labeled flood injury, it doesn't mean that there needs to be a flood for the injury to occur.  There just needs to be an unusual excess of water.

Flood injury is a serious matter concerning the health of your trees. Please stay tuned as in the next few days I will cover the symptoms of flood injury and what you need to do if your tree has been affected by flood injury.

If you feel your tree was affected by flood injury, please contact your local tree service or arborist to determine the extent of the damage and to see how the tree can be saved. Trees "R" Us, Inc. is a tree service with certified arborists on staff to help you with your tree care needs such as this. If you are local to the Chicago suburbs or North Shore area of Chicago, please contact us with your tree care concerns. 847-913-9069 or www.treesrusinc.com