If your tree’s leaves are starting to appear, you may think that the tree is in the clear as far as
drought damage goes. However, during periods of severe drought, a tree may lose a significant portion of the root system because roots cannot live in soil that is dry for long periods of time. Also, the tree has used a good deal of energy and its reserves trying to keep itself cool in the hot temps and dealing with reduced water uptake. The tree will also have a difficult time fighting off insects and disease. So, how do trees recover from severe drought conditions?
WATER! Proper tree care requires that you monitor the soil moisture. Use a garden trowel or a screwdriver to check the soil moisture 2” below the surface. If it is dry, then it is time to water. Sometimes a lawn irrigation system will not water deep enough to reach the tree roots. You may need to pull out the hose to soak the soil. You want the soil to be moist but not soggy.
Maintain 1-3” of mulch around the base of the tree, but avoid mounding it against the trunk of the tree. Mulch protects the trunk from mower and string trimmer damage, maintains soil moisture and adds nutrients to the soil as it decomposes.
Monitor the tree for any signs of insect or disease problems. By catching the problem early and correcting it, you can help the tree fight off the problems it may not be able to handle on its own. Click the buttom below if you would like a licensed arborist to inspect your trees.
For a new tree, the only tree pruning that should be done the first year would be to remove any dead, damaged, or diseased branches. After the tree has been planted in the ground for one year, you can begin to prune the tree to improve structure and aesthetics. This may need to be done each year until the tree has a strong, balanced structure. Training young trees optimizes structural stability in the mature tree. By pruning a tree when it is young, you can avoid problems such as co-dominant stems, weak branch attachments, and crossing branches. This can greatly reduce the maintenance costs associated with correcting these structural defects in the future.
For a mature tree, how often you need to prune will depend on the history of the tree. If it has been well maintained through the years, the only pruning that may need to be done would be to remove any dead, damaged, or diseased limbs. If the tree was not properly trained when it was young, it may have problems such as splitting branch attachments, branches that are too low, or other structural defects. Typically, removing more than 25% of a tree’s leaf area during one growing season should be avoided. The tree may need to be pruned once every few years until it has good structure and aesthetics.
As always, we recommend consulting a licensed arborist before pruning.
The Emerald Ash Borer (EAB) is an invasive insect that has destroyed tens of millions of ash trees in North America and Canada since 2002 when it was first discovered in Michigan. The beetle is native to Asia and was brought to the US by infested wooden pallets. It attacks all ash trees, regardless of age or health. Trees become infested when adult beetles lay eggs on the bark. The eggs hatch into larvae that bore into the tree. They tunnel just below the bark and disrupt water and nutrient movement, eventually killing the tree.
Until recently, the closest the pest had been to the Omaha area was in extreme north east Iowa in Allamakee County. On July 20 of this year EAB was discovered in the Kansas City area and on Aug 29 it was discovered in Wyandotte County in Kansas. The borer is usually spread by moving infested firewood to campsites around the country.
The recommendation that the Nebraska Forest Service is using for when to begin preventative EAB treatments, which other states are using too, is not to begin treatments until you know EAB is within 15 miles of your location. We will continue to keep you up to date on the latest EAB news. There are several chemical treatment options that have proven to be effective in protecting ash trees from the devastation of EAB. While it is not impossible to save an ash tree once it has started to show signs and symptoms of an EAB infestation, the success rate of keeping an ash tree alive is much greater with preventative treatments. Symptoms can be difficult to recognize because many of them look very similar to the effects of drought stress on trees.
Some signs and symptoms of infested trees include:
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Thinning canopy
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Branch dieback from the top of tree
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Delayed leaf out in the spring
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Woodpecker damage
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Epicormic shoots/water sprouts
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Bark splitting
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D shaped exit holes
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S shaped tunneling under the bark
If the thought of losing your ash tree concerns you and confirmed sightings within 15 miles is too close for comfort, contact us and we will have a professional arborist take a closer look. We can answer any questions you may have regarding appropriate preventative treatment measures.
For more information on the devastating destruction of the Emerald Ash Borer on our ash trees, visit www.emeraldashborer.info
Not sure if you have an ash tree? Email a picture to admin@cmscustomlawn.com
Fall provides great planting conditions for trees and many nurseries offer discounts at this time of the year. If you finally made the decision to add a new tree to your landscape this fall here are a few tips on how to select a quality tree from the nursery and properly plant to ensure a long healthy life.
Selecting: When you go to your local nursery you will find that tree prices can run fairly steep compared to a big box store garden center, but don’t avoid going to a nursery because of that. Privately owned nurseries tend to have higher quality tree stock, offer longer warranties, and support local growers. No matter where you go, it is good to know a few hints on how to spot a good tree.
· It is important that the tree has a visible trunk flare (area where the trunk expands to the root ball). This is a sign of proper growth and strength.
· Inspect the tree for any damage to the bark, uneven branch distribution, and lack of new growth.
· Examine the foliage as signs of stress are easily visible by looking at the canopy of the tree! If the tree has been suffering it will be difficult to transplant and it could possibly die, wasting your money and time. Leaves should be full, large, and green depending on the type of tree and time of year.
· Some larger trees come in ball and bur lapped bags. Check to make sure the twine does not girdle the trunk and the root ball is moist. With smaller potted trees you can sometimes pull the tree out of the pot to examine the roots. Roots should be a healthy light color and fit snugly in its container.
Planting: To ensure that your newly selected tree lives a long healthy life it is important to plant it in the right place. Improper planting leads to a lifetime of disease or insect problems and often times death. Here are some simple planting tips that help improve the health of your tree.
· When digging a hole it is common practice to dig 2 to 3 times larger than the width of the root ball, but no deeper. The trunk flare should be a couple of inches above the ground level. Throughout time the tree will settle, but there is no need to amend the soil.
· Always be gentle when removing the pot and be sure to loosen up the root system. Place the tree in the middle of the hole and back fill with the previous dirt, lightly packing, not stomping, the soil.
· After ball and bur lapped bags are set in the hole, cut the twine and the top-most portion of the wired cage.
· Always water the tree immediately after planting. If the tree is large, you can water while filling the hole back up with soil. Infrequent deep soakings are recommended for the first year after a planting.
· Some trees may need staking. Be sure to monitor the stakes as they may require adjustments. Depending on the tree, stakes can be removed after 1-2 years.
· Mulching is a great idea because it helps maintain moisture, keeps weeds away, and maintains a cooler soil temperature. You only need 2-3 inch thickness. Avoid stacking mulch against tree bark to prevent restricting roots and causing disease.
Check out ReTree Nebraska’s 12 for 2012 for recommended species in our area
We know trees create oxygen, provide food, shelter, and lumber, but how else do trees help the average suburban home or business owner? Here are a few benefits to consider while the season of tree planting quickly approaches.
- Environmental: If your house is built in an area with high winds and intense sunlight, trees properly planted on the south and/or west sides of your house can save up to 30% on energy costs. Trees also reduce storm water runoff, improve soil erosion, and even work as an oxygen pumping machine for all those who might live in a highly polluted area.
- Aesthetic: Did you have a special tree during your childhood that was the focal point of your summer
fun? Tree houses, tire swings, apple picking, and tree climbing all seem to be an essential part of growing up. Do you have an area of your landscape that is just missing that something special? A tree can be the cure! You can even plant a few ornamental trees to enhance an area for more beauty. Crabapples, pears, and cherry trees are just a few of Omaha's favorites.
Economic: Trees can enhance the value of residential and business properties. Studies have shown that trees also play a huge role in attracting visitors, businesses, and new residents. The shade of a great canopy can reduce the maintenance on materials that might be easily degraded by heat, such as siding.
Come back next month for our discussion on tree selection and planting.
I'd like to go by climbing a birch tree, and climb black branches up a snow-white trunk. Toward heaven, till the tree could bear no more, but dipped its top and set me down again. That would be good both going and coming back. One could do worse than be a swinger of birches.
-- Robert Frost, Birch Trees
Not to my surprise, river birches are one of the most popular landscape trees in the Omaha area and all for good reason considering their beautiful peeling bark, convenient medium size, and magnificent fall color. People have fallen completely in love with these trees, but of course just like any other tree it has its challenges, especially at this time of the year, so be sure to keep an eye on your most valued specimen. The issues that I have been seeing are treatable. Here are the most common:
Leaf Drop: Usually during the middle of a hot dry summer, birches get a little stressed and like to lose some of their inner leaves. This helps to conserve energy by preventing water loss through evapotranspiration. Be sure to check the soil around your tree to make sure that it is getting sufficient water. The river birch is aptly named. If there is a period of a long harsh drought don’t be afraid to give your birch a few minutes of watering a week until we get some rain. Mulching is also a good idea to keep the root system cool and moist.
Iron Chlorosis: Signs of a chlorotic tree are found on the foliage where the leaves are turning yellow but the veins are still green. This is caused by a combination of an iron deficiency and soil pH surplus for these trees that like a more acidic 6.0 to 6.5 range. Simple soil tests are available at your local nursery that can help to determine what range your soil is in. Soil amendments are also available and CM’s also offers an iron injection to help green up any tree that might be showing signs of chlorosis
Japanese Beetles: Even though birch trees are not Japanese Beetles’ first choice of a meal, I have been seeing them munching around on their delicate little leaves. These beetles are shiny green with brown wings and leave little holes all over the foliage. And if you find them in your trees they are most likely in other areas of your yard as well. Luckily their season is slowly coming to an end but if you still see them buzzing around there are a wide range of pesticides available that can fight them off. CM’s offers a spray containing bifenthrin that kills them on contact.
Please be sure that your tree is properly diagnosed before any treatments are made.
What are these mobile bags of destruction on my most prized plants?
Those contain bagworms. In your trees and plants, they do anything from eat and nest to reproduce by the hundreds. One season you will see only a few and the next there will be many more than you anticipated (about 500-1000 eggs per bag). All the more reason to act fast when they are first spotted.
Identification is the number one thing to consider when you are planning to control a pest. Bagworms are easy to spot by their dangling bags on plant material. They are anywhere from one to two inches long and are usually brown in color. Inside are little pupae. At this point in the season they are young male and females which do not start mating until September. In the beginning of summer, they poke their little heads out and move along branches and stems eating or collecting needles or leaves to add onto their bag. This can result in a devastating amount of defoliation if left untreated for too long. The most common host plants are a selective group of deciduous trees and shrubs as well as a wide range of evergreens. Sometimes a pine cone can be mistaken for a bagworm, so take care to be very observant.
Controlling bagworms can be very simple and there is plenty of ways to do so. If you just have a few of the little buggers hanging out you can just pluck them off and discard them. We suggest burning or drowning them in soapy water because they have a sneaky way of moving around and finding their way back to your beautiful tree or shrub. If you have a lot of wildlife living in your backyard, bagworms become a great meal for the birds during the fall and winter seasons. Late June to early July is the suggested time for spraying the pupae. There are pesticides available from your local nursery, but follow the label to get the most effective results. Preventive injections can also be done on an annual basis. CM’s tree care program offers prevention and treatment of these harmful insects.
Surface roots can be more than just a nuisance; they can also pose a tripping hazard. While trees will send some roots down deep for moisture and stability, the majority of tree roots grow within the top 4-8 inches of the soil. As the tree ages and matures, the roots expand in girth and make their way to the surface. Some trees, like Silver Maple, will have more surface roots than others, but usually at some point all trees will have at least a few roots coming to the surface.
Each large surface root is attached to many fine feeder roots. By severing one large root, a large supply of vital nutrients and water is lost. If several large surface roots are cut, the tree’s stability can be compromised.
Covering the roots with excessive soil and sod has a similar effect on the tree as cutting a root would. By covering the woody material of the surface root with soil, the wood will eventually rot and kill that particular root. This also cuts off a large supply of vital nutrients and water.
The best way to deal with surface roots is to carefully landscape around them. Either plant a ground cover that will not need to be mowed or plant small perennials under the tree, taking care not to disturb the root system of the tree. A layer of mulch 1-2 inches deep can be added around the plantings and on top of the tree roots without causing damage to the tree.
So maybe hostile is overreaching. It is fair to say that citrus trees and Nebraska don’t come up in conversation together very often. For those of you who want to defy Mother Nature here is your chance. You can successfully grow citrus trees in a potted environment in our region!
Selection: Choose a small or dwarf variety of citrus tree. Citrus trees are not cold hardy in Nebraska so you will need to bring your tree indoors for the winter. Some varieties of citrus will mature to a height of 20 feet. Although trees grown in a pot will not reach their mature height, a larger variety may still grow to a size that will be difficult to manage. Choosing a variety with a mature height of 8’-10’ will make the task of caring for them much easier.
Overwintering: Citrus trees are generally hardy to zones 9-10. For potted trees growing in Nebraska, this means they will need to be moved indoors whenever the temps drop below 40 degrees. It is normal for the tree to drop some of its leaves while indoors. Citrus trees need six to eight hours of direct sunlight. A room with a sky light or a south-facing window is ideal.
Watering: Citrus trees prefer to have their roots kept moist but not soggy. If the tree is planted in appropriate soil with good drainage, water the tree daily during the summer months. When the tree is moved indoors it will need less water because its metabolism will slow down. Water approximately once every 10 days.
Soil: Well drained soil is important for citrus trees. They prefer dry, sandy soil. If a potting mix blended specifically for citrus plants is not available, you can mix your own. Use about one-third potting soil, one-third perlite or vermiculite, and one-third peat or other organic matter for the potting mix. A potting soil blended for cactus will also work well.
The Container: When selecting a container to plant your citrus tree in, use one that is about 6 inches larger in diameter than the container your tree was sold in. Look for a container with plenty of drainage holes. Repot your tree every two to three years.
Fertilizing: Citrus trees are heavy feeders and perform best when they are fertilized about three times per year. Use a fertilizer that is specifically formulated for citrus plants and follow the feeding instructions on the label.
The Fruit: Most citrus will take six months to one year to mature from flower to ripe fruit, depending on the variety and cultivar.
Whether you are looking for something fun, something more colorful, or some zing to add to a cool summer beverage, give citrus trees a try! Bright and vivid goes just as well in Nebraska as it does anywhere else.
We received the following question from Patti: "We have an Autumn Purple Ash tree which grows 'shoots' from the ground right at the base of the trunk. If we don't trim them down every few weeks or so, it becomes a 'bush' and looks very unsightly. Is there something wrong with the tree, or is there something else we can do to stop this?”
Thank you for your question Patti!
There are several reasons why a tree will start to grow ‘shoots’ or suckers from the base of the trunk. For some trees, like many varieties of Crabapple trees, suckering is simply part of their growth form. The tree can be completely healthy and grow suckers profusely just because that is how it wants to grow. If this is the case, there are a few ready-to-use products on the market that are meant to slow sucker growth. However, if this is a new issue for a mature tree, it is most likely a response to some sort of stress affecting the tree. Stress factors can include insect infestation, disease, or if the tree has recently been over-pruned or has suffered significant storm damage. Sucker growth can also be an indicator that the tree has been planted too deep or that there is a moisture issue.