Tree Searching

Information and knowledge are not the same. Online search engines have a wealth of information but they may not impart any knowledge that is of use to the seeker. A popular TV commercial has people conversing using information searches from various search sites and it ends up in meaningless chaos.

What does this have to do with the care and preservation of trees? Plenty. If you were looking for a particular plant disease, for instance, Rhizosphera needle cast , a disease that can seriously injure Colorado Blue Spruce, your search is just as likely to end up looking at knitting needles or plaster cast construction guides. While this information is extremely useful it may not be the knowledge that you need to see what is defoliating your trees.

Chronic Google Heads spend hours trying to sift through useless information for a kernel of sound knowledge. How do I know this? more and more often while meeting with new clients I have to impart knowledge that I have gained through rigorous study and years of field observations to counter a few hours of Google searching. Some information is just not relevant to the particular species or cultivar, and other information is excluded because of geography, climate or soil conditions.

On one hand I am excited and encouraged by the clients enthusiasm and energy to help their plants, on the other hand it is discouraging to see so many people being side tracked by useless information. I guess that was part of my original purpose for writing this series of monthy press releases over the past 8 years.

The starting point for identifying tree and shrub problems is always correctly identifying the plant, and then the disease or insect that is affecting it.

The missing link in all this searching is a dedicated, informed expert who is capable of determining what is the best course of action to correct the problem your particular tree or shrub is having. Sometimes the best action is no action!

I.S.A.Certified Arborists are knowledgeable in identifying trees, shrubs and the diseases and insects that affect them. Take the time to consult with your Certified Arborist if you suspect your tree has a problem that may reduce its ability to thrive. The knowledge you gain will benefit your trees and save you time by not becoming Google-mired.

Lichen, Moss, and More

Every couple of weeks I get a call to go out and look at a terrifying disease that is threatening someones prize specimen tree. It is easy to make light of this, but the sense alarm felt by the home owner is genuine, and one should never make fun of someone who is genuinely concerned with the health of trees. Typically these calls come after a soaking rain when the bark of the tree erupts into a verdant green carpet, or possibly a gray-green bouquet of fronds. The culprits are two ancient inhabitants of the forest, that may even predated the arrival of trees. Lichen have been around for at least 400 million years and their neighbors the moss are found in the fossil record back to the beginning of the Permian period, 300 million years B.P.

Moss, a fuzzy or sometimes minutely leafy, non vascular plant, is classified in the group of plants know as Bryophyta. Moss plants will grow on most moist shady surfaces like rocks, trees and soil. They prefer not to be exposed to direct light and therefore are most often found on the north side of tree trunks. Moss plants need free moisture to complete there life cycle but will survive for long period of time in a dry desiccated state. If they receive sufficient moisture they will “green up” and come to life with in a short period of time, seemingly overnight. Moss does not have the waxy outer leaf layer known as the cuticle that prevents most higher plants from drying out. Moss are able to survive on what amounts to essentially dust and rain drops. They do not harm trees and do not digest the bark they are attached to.

Lichen on the other hand are not really considered plants at all but are a curious symbiotic relationship between a fungus and an algae. The fungal partner provides nutrients and a physical structure for the algae. The algal partner is able to photosynthesize and create sugars to feed both partners. Both partners present in lichen gain moisture and nutrients from the atmosphere. It is rare for them to take any nutrition from a tree that they are growing on. Lichen are usually larger than moss and have a blueish green color. The algae partner may be a blue-green algae which would explain the lichens color. Lichen can have several different forms from crusty or crustose , or foliate forms that resemble leaves, called foliose. Lichens simple structure means they are unable to avoid the accumulation of damaging pollutants. In fact they can be used as a measure of air quality. A decline in lichen populations is indicative of high levels of pollution. The presence of moss and lichen usual indicate moist conditions, and reasonable air quality. The presence of mushrooms and other fungi may be more serious.

I.S.A.Certified Arborists are knowledgeable in identifying moss, lichen and dangerous tree fungi. Take the time to consult with your Certified Arborist if you suspect your tree has something more serious than moss .

Any Ash is Good Ash?

Photo K. Arrell

When I was learning to identify trees I had an instructor who was great at coming up with catch phrases to remember tree I.D. I still remember his comments on ash trees which I have used as the title for this article. Ash trees have long been prized for its adaptability, survivability and versatility. Lately it has also been in the news for its susceptibility.

Anthracnose is a common fungal disease of both green and white ashes. It occurs seasonally in spring and can result in the defoliation of the lower third of the tree. Buds, twigs, and leaves can become infected. Typically leaves will exhibit irregular or sickle shaped distortions as well as blotchy lesions.Severely impacted leaves may be shed from the tree and should be removed from the area as they are a source of reinfection. On occasion the disease may attack the petiole, or leaf stem resulting in extensive defoliation. Cultural practices general are effective in reducing the extent of the disease and preventative fungicides applied at bud break should only be used as a last resort.

Ash yellows is a vascular disease of ash trees is caused by a phytoplasm, a type of microbe. Both white and green ash are affected as well as a dozen other ash species. Susceptibility varies among species and individual trees with the most severely impacted trees dying within months. More resistant trees may last for years with various symptoms. Stunted sickly growth, and the presence of witches brooms, thick broom like growths, are the main symptoms. This disease is spread by insects that feed on leaves by sucking sap. Maintaining the vigor of less severely impacted trees may prolong their lives, heavily impacted trees should be removed.

Ash plant bug is a native pest that does damage to ash leaves by inserting its sap sucking mouth parts into the upper surface of leaves. This action causes yellow stippled areas that may coalesce into large yellow patches. The feeding may cause browning and distortion of foliage that can be confused with anthracnose. One key way to differentiate between the two is to look at the underside of the effected leaves and you may find black spots, waste from the plant bugs called frass. These insects have two generations per year and may cause extensive damage. They are easily controlled by a number of insecticides applied early in the season , including horticultural soaps and oils

Emerald ash borers are a newer introduced threat to ash trees. The original infestation was probably the result of green wood in the form of packing materials that originated in the beetles home range, Eastern Asia. The adults themselves feed on the leaves of ash trees but cause little damage. In late June to early July, they lay their eggs on the bark of ash trees usually in cracks crevices and fissures. The eggs hatch, burrow into the inner bark, the cambium layer, and begin to chew their way though the vascular cambium in up to foot long serpentine feeding galleries. The tree is unable to survive the injury to its vascular system, starts to wilt and die back and will last only one to three years once infested. Avoid transporting ash nursery stock or fire wood.

I.S.A.Certified Arborists are knowledgeable in identifying ash disease and insect problems. Take the time to consult with your Certified Arborist if you suspect your ash tree has problems.

Root Self Exam

Few tree failures are as tragic as ones caused by girdling roots. This condition, caused by roots that have circled the main trunk growing to eventually strangle the tree, results in a slow decline and eventual death of trees in their prime.
This condition can occur with a wide variety of trees, maples, cherries, plums and pines are a few on the ones I have personally observed in the last few months.
Normal root systems extend from the root flare at the base of the main stem and move away from the stem like the spokes of a bicycle wheel. The roots that cause trouble, circle around the tree and constrict the main stem. Tree roots that cross other roots further away from the main stem cause little damage and my even form unions or grafts that result in no damage at all.
If you let the girdling roots go unchecked they will eventually cause the tree to die back and decline to the point of failure.
Fortunately you can easily observe tell tale signs that are indicative of root problems on your own trees.
Trees should have a basal flare where the main stem meets the soil surface. This sometimes pronounced swelling should lead from main stem to root in smooth curve.
Flattening of one side of the stem can indicate a buried root that is pressing on the main stem and causing stress on the trees vascular system. The root actually compresses the tissues of the tree preventing the movement of water up the stem and nutrients down to the roots. You may even see decline on that side of the tree. Small leaves and reduced growth on one or more sides is another typical symptom. If you are able, grasp the tree and slowly shake or try to move it, it should be firm and not rotate. Small trees with girdling roots will move like the stick shift in a manual car.
Occasionally, the tree will not display any outward obvious symptoms yet will fail when extreme weather conditions overwhelm the trees circulatory system. Periods of drought or extreme heat can result in this type of failure. Once the tree has failed a close examination will reveal the obvious signs of girdling roots. Take a look for these telltale signs:

Large roots that are visibly crossing the trunk of the tree
Lack of typical root flare on one or more sides of the tree
Yellow or smaller leaves on one side of a tree
Recessed, inverted or flattened root flares that curve inward like the point of a pencil
Instability in small trees when manually shaken or pushed

I.S.A.Certified Arborists are knowledgeable in identifying and correcting girdling root problems. Take the time to consult with your Certified Arborist if you suspect your tree has rooting problems. You may be able to limit the damage caused by girdling roots and prolong the life of your tree.

Lessons Learned From Dutch Elm Disease

Dutch Elm Disease, a typically fatal vascular fungal disease of North American elms, has been around a long time. It was first described in the 1920's in Northern Europe but soon made its way to North America and was wide spread in Eastern North America by the 1950's. Shade tree committees and tree surgeons alike mobilized or try prevent or slow the spread of the disease. Depending on climate and success in controlling elm bark beetles, a vector for spreading the disease, there were some successes. There were however tremendous losses in areas where the type and behavior of elm bark beetle was not conducive to control or where people were slow to organize to control the spread of the disease. While elm bark beetles are the primary vector for spreading the fungal disease they need habitat that is suitable for them to survive and thrive. Native elm bark beetles have a life cycle that is limited to one generation per year and they overwinter by burrowing into the bark at the base of elm trees. This leaves them susceptible to control methods that target them while they are overwintering. European elm bark beetles have a different life cycle that does not allow them to be controlled using these methods. However European elm bar beetles, do not survive extremely cold winters and this has prevented them from migrating much further north than the State of Minnesota. Winnipeg, Manitoba along with other Western Canadian cities now have the largest intact urban elm forests in the world. The survival of these forests would not have been possible without cost or the ongoing efforts of generations of concerned professionals and citizens alike. These costs are minor compared to the value of the resources protected.
But what lessons have been learned from this on going battle? Beyond the species and disease specific lessons, the need to actively care for and manage urban trees and the greater urban forest has been the most important lesson learned. Many of the current generation of I.S.A. Certified Arborists had there first experience in arboriculture in the battle to fight Dutch Elm Disease.
The second great lesson learned is the necessity for diversity in our urban plantings. In some areas at the height of uncontrolled Dutch Elm Disease epidemics, towns and villages lost in excess of 50 percent of their forest canopy. The planting of single species urban forests should have stopped but this was not always the case. In many areas towns and villages are now losing their replacement canopies of ash to emerald ash borer.
The third lesson that should have been learned is that trees add tremendous value to our urban environment. Not only the intangible “feel goods” but real dollars and cents benefits. Increased property values, effects on heating and cooling, storm water retention are just a few of the benefits that we can actually calculate.
I.S.A.Certified Arborists are knowledgeable in tree preservation, selection and planting. Take the time to consult with your Certified Arborist before you undertake tree planting and your landscape will maintain it's diversity and value for years to come.

Planting and Selection Quick Tips

Tis' the season to roll up your sleeves and dig in to the dirt!
Before you head out to your local nursery take a few moments to considered the following tips before purchasing or planting a tree or shrub,

Location location location,
You will have greater success if you have already determined the location you wish to plant and its attributes.
What is the sun exposure? All day, part of the day, under a forest or tree canopy?
If grass won't grow in the location it is probably best suited for shade plants.
There are a number of trees and shrubs that grow in the understory of the forest.
Most fruit trees require a lot of sun, generally these must be planted in full sun to archive good growth and fruit production. Soil is important not only in quantity but in quality and depth as well. Trees that like to have cool moist roots will not thrive in rocky areas or rock ledges covered in soil. It is always a good idea to dig a test hole before you purchase a plant for a particular location.

Selection, selection selection,
When you are at the nursery look for fresh healthy stock, go early in the day when crowds are less and you can take time to pick out the best stock. Good form and branching habit will pay rewards long after you plant your tree or shrub. The plant with the most flowers isn't necessarily the best or most healthy. Look for good leaf color and signs that the tree has been handles well. Broken twigs, disturbed soil, or scuffed containers can indicate the plant has been dropped off a forklift or worse. Check the root collar to ensure rodents or insects have not girdled the bark and damaged your potential new tree. Take your plants home promptly and plant them, cars are not greenhouses and are an abrupt change from the nursery environment. Lastly water your plants thoroughly once planted to eliminate air pockets in the root zone and improve the chances of survival.

Certified Arborists are knowledgeable in tree preservation selection and planting. Take the time to consult with your Certified Arborist before you undertake major tree planting and your landscape will maintain it's value for years to come.

Tree Support Systems, Props

Occasionally as a result of a storm or old age trees will loose their ability to remain upright.
The obvious option is to take the tree down and plant another one to replace the damaged one.
However when a tree fails or begins to fail in our yards people have come up with interesting ways or supporting them and allowing them to continue to survive and even thrive.

When people become attached to trees in their environments they will work tirelessly to preserve and lengthen the life span of “their” trees. This is a sentiment and passion that I share as an Arborist and person who appreciates all aspects of trees. If a tree falls in the forest, free from humans who rightly or wrongly have sentimental attachments and impose their mortal shortcomings on trees, it falls to the forest floor and is recycled.
In your yard this may not be the option you are looking at first.

Cables, braces and ground anchors are used frequently to stabilize trees that are falling over or are in danger of falling over. This article will focus on an other lesser used method, the tree prop or crutch. Just like the crutches used by people when they have broken limbs the tree prop is a sturdy typically wooden post used to support a broken limb or leaning tree. The ideal basic prop is composed of a sturdy rot resistant wood, such as oak, cedar, or locust. The top should have a
u shaped crotch that is capable of supporting the tree or limb that is failing. The prop, or props should be of sufficient diameter to support the tree or branch it is placed under.

Trees are living organisms with their vascular tissues living anf functioning just under their bark. Any prop system has the potential to damage the vascular system and this should be considered,
Attaching props by lashing them to the tree should be avoided, unless the lashings are replaced and re worked every year as the trees grow and expand. Crutches with v or u shaped branch rests should be inspected and adjusted frequently to prevent partial or complete restriction or girdling of branch tissue,

Tree lovers have come up with many ingenious systems to support and maintain our tilting trees.
It is important to make sure whatever system you have it is safe and will not fail suddenly endangering people or pets. Keep in mind that the props are usually dead wood and are decaying while the branches they are holding are alive and getting more massive with every season.

Regular inspection and pruning are a must if you are propping up aged trees. Certified Arborists are knowledgeable in i tree preservation and maintainance. Take the time to consult with your Certified Arborist before your tree is tilting or in danger of failing and your landscape will maintain it's value for years to come.