Jun 01, 2022 - 12:51 pm CDT

Small bur oak that is half dead

This small tree might survive, but the wiser choice may be to replace it with a new, healthy specimen.

Tree damage from Winter Storm Uri, a major freeze that hit Texas in February 2021, is still visible all around Austin. Trees that had begun growing new spring leaves were hit the hardest. Species showing significant damage included huisache, red oak, crape myrtle, and lacebark elm. The biggest concern we have now is our ash trees. A lot of them suffered from the freeze, but they also are at risk from an invasive beetle that could kill them in the near future.

 

Ash tree with dead branch tips

The tips of these branches are dead. They are small enough not to pose a risk.

Safety First

Safety must be our first concern. A tree over a sidewalk or play area must be thoroughly pruned to avoid having people injured by falling debris. We don’t have to be as concerned if there is nothing under the tree to be damaged. We can prune for aesthetics or just let the dead branches fall naturally over time.

If there is a potential for harm to a person or property, the level of risk rises. This can be difficult to assess. For large trees that might cause severe damage, a qualified arborist can help you assess the risks and decide how to mitigate them.

Options for large trees may include:

  • Close monitoring at least annually
  • Pruning out dead branches
  • Complete tree removal.

If a protected Ash tree is deemed to be a hazard to life and property and will be removed, a Dead, Disease, & Imminent Hazard (DDI) permit must be submitted to the City Arborist Program. This will also apply if more than a quarter of a protected size tree will be removed.

 

Large ash tree with only one live branch over a parking lot

This large ash tree is almost completely dead. It is over a building and a parking lot. It should be removed.

Special, but not in a Good Way

Ash trees are a special concern. Even before the storm, many ash trees in neighborhoods built in the 1960s and 1970s are nearing the end of their expected life spans. We also must consider the risk from an invasive insect, Emerald Ash Borer (EAB) that makes trees very hazardous, very quickly once they've been infested. You should carefully consider the expense of treatment for EAB and decide if your tree is worth it. Though we hate to lose any trees, the wisest choice might be to remove a weakened Ash tree and replace it with a more robust species. A professional arborist can help you make this assessment. 

Visit the Grow Green Program and its searchable plant guide for tree species that do well in Austin. 

Article by Keith Babberney, Education Forester, City of Austin, Development Services Department, Urban Forest Program.

 

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www.austintexas.gov/trees

 

Tagged:
Dec 13, 2021 - 11:47 am CST

Ash tree with red and white warning symbolAlert! Tree emergency!

You may have seen our recent posts where we warned you about an invasive insect, Emerald Ash Borer (EAB). This pest could kill all our ash trees within a few years, so we need to prepare now! In the earlier posts, we encouraged you to help us find Ash trees and map them using iNaturalist. We hope you will also keep watch for signs of the insect in our area. Early detection is key to saving as many trees as possible. Now you should take a close look at the ash trees you found. You must decide if you want to protect them against the insect when it arrives. 

What Is Your Ash Worth?

The first step is to decide if the tree is worth saving. We hate to lose any of our trees, but sometimes removal is the best option. We would have to commit to years of expensive treatments to protect any ash tree against EAB. It often makes more sense to replace a weak tree with a more reliable species. Several factors might affect your decision.

In Austin, it was common to plant Arizona Ash in new developments around 50 years ago. The lifespan of an Arizona Ash is rarely much longer than this. In other words, these trees are nearing the end of their lives no matter what we do. Older trees also may have problems with decay and structure that make them likely to break when stressed. No matter what we do to care for them, they are likely to fail or die within a few years. 

Younger trees may still have some good years in them. Also, some ash species are less prone to the structural problems of Arizona ash. These are more likely to merit treatment. A qualified arborist can help you assess your trees and the associated risks.

Trunk of an ash tree showing decayed and splitting wood.

If your tree is in poor condition, you might choose to remove it instead of treating for EAB.

Save your ash!

After you consult with an arborist, you might decide to keep your trees. Next, you should prepare to have the trees treated. Trained professionals can inject a chemical into the tree which will then kill any insects that feed on it. You will need to repeat this treatment every 2-3 years, so it can get rather expensive--even more so for larger trees. Still, treatment is the only way we have found that is likely to be successful against EAB.

Unfortunately, a lot of our ash trees were damaged during the extreme freeze of February 2021. This damage may be hard to distinguish from EAB for the next few years. Some may have been so badly frozen that they will not recover. A qualified arborist can help you determine the cause of your tree’s decline and how to manage it.

Ash trunk being injected with insecticide

To preserve ash trees in the presence of EAB, we must treat them with a chemical insecticide. (photo courtesy Matthew Karst).

When to treat

Timing of these responses is tricky. If we treat now, the chemical may lose effectiveness before EAB arrives. Ideally, we will have lots of advance warning. If we see it coming, we should begin treating when the insect is within 10-20 miles from us. Unfortunately, we might not get such notice. Often, EAB is in a city for years before symptoms are severe enough to recognize. You should prepare for a rapid response.

If you intend to save your tree with chemical treatments, you would be wise to find qualified help now. Companies that treat for EAB are likely to be extremely busy in the first weeks after the insect arrives. If you already have a plan in place, you are more likely to be among the first to receive service.

Proactive removal

If you decide your tree is not worth the expense to save it, you might want to let it die naturally, then have it cut down. Unfortunately, this probably won’t be the best option. It’s a difficult decision, but an important one, so take the time to consider all factors.

With an EAB infestation, tree removals become far more hazardous and expensive. The borers weaken the wood dramatically. Trees begin to fall apart much more quickly than those that die from other causes. This is such a pronounced effect that climbing them is too dangerous. Experts recommend using mechanical lifts or other expensive equipment to remove ash trees killed by EAB. Companies with this equipment will be very busy once EAB is here. Proactive ash removal is likely to be much cheaper than waiting until a tree dies from EAB.

Aerial lift truck with bucket extended

Trees killed by EAB become very weak. They must be removed with expensive equipment.

When to remove

How do you know if it is time to remove your ash tree? You could cut the tree down any time before EAB arrives and have no problems related to the insect. Be sure the company you hire has liability insurance to protect you and your property. If you have doubts, don’t be afraid to copy the policy information and call the insurer directly to confirm.

If your tree is larger than 19” diameter at breast height, you must get a permit to remove it (per Austin's Land Development Code). The City Arborist will consider most residential ash trees “Dead, Diseased, Imminent Hazard.” In these cases, permit fees and remediation will not be required. You can start the permitting process at the City website.

Phased removal

If you have the budget, you might decide to take a phased approach. Have a company start removing the most extended, hazardous, or hard-to-reach parts now. Plant a replacement tree (not an ash) in the gap they create. This reduces risk in the short term while the new tree becomes established. You can remove the rest of the ash tree later.

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This information is sponsored by the City of Austin. Learn more about trees and resources at the Tree Information Center!

Nov 17, 2021 - 04:17 pm CST

Ash tree with red and white warning symbol

Alert! Tree emergency!

You may have seen our recent post where we warned you about an invasive insect, Emerald Ash Borer (EAB). This pest could kill all our ash trees within a few years, so we need to prepare now! In the earlier post, we encouraged you to help us find Ash trees and map them using iNaturalist. While you’re working on that, we hope you will also keep watch for signs of the insect in our area. Early detection is key to saving as many trees as possible. A quick response will also help reduce the dangers to life and property that EAB-infected trees can cause.  

What is EAB? 

Emerald Ash Borer (Agrilus planipennis) is a beetle from Asia. It probably hitchhiked to the USA in a packing crate or other wood product around 2002. It causes only minor problems in its home environment, but it has no natural predators here. It reproduces rapidly and the population destroys trees within a few months. No ash trees can be expected to survive an attack of EAB without chemical treatments to protect them. Hundreds of millions of trees have been killed in the US since EAB arrived here. 

The beetle arrived in Michigan over twenty years ago and has since spread to 35 US states and 5 Canadian provinces. It was first found in Texas near the Louisiana border in 2016 and is now known to be in six Texas counties. We still have not found any of them in Austin, but a beetle or its eggs could arrive any day on a load of firewood or other cargo.  

Let’s learn what to look for so we can respond in a timely way. Then we can protect our best ash trees against EAB before it kills them. 

Shiny and Green 

The insect is small and easy to overlook. The most striking detail is the shiny, green shell that sometimes glitters gold, copper, or purple in sunlight. Its body is less than half an inch long and an eighth of an inch wide.  

Adult Emerald Ash Borers on a penny for size reference, exit holes visible.

Two adult Emerald Ash Borers with a penny for size reference. Note “D”-shaped exit holes to the left. Image courtesy newbruswicktoday.com 

When it flies, the green shell opens to reveal its bright, red body.

Adult EAB with wings spread to show red body underneath.

Adult Emerald Ash Borer with wings spread to reveal red body underneath. Image courtesy USDA-APHIS. 

If you see an adult EAB, please try to get a photo and report it. The iNaturalist app and website are one good place to record your find. You can also report it to Austin’s Urban Forester via 311, send an email, or contact the Texas A&M Forest Service

Larvae 

Adult beetles eat some leaves from our ash trees, but the larvae cause the real damage. The adult lays eggs on the bark in late spring. When they hatch, the larvae chew into the bark and begin eating the tender sapwood just beneath it. By the end of summer, the larvae may be as long as 1.5 inches.

EAB larva in an ash log with bark removed

EAB larvae chew tunnels through sapwood. This one is exposed in its tunnel because the bark has been removed. Image by Pennsylvania Department of Conservation and Natural Resources. 

Galleries 

We will keep our eyes open for adult beetles and larvae, but we are more likely to find the insect based on the tree’s reaction. EAB can feed on trees unnoticed for some time before symptoms appear. In a tree that has been attacked by EAB, we may see bark peeling off. There will be serpentine tunnels, or galleries, underneath. Even without seeing a larva, this is a strong sign we have found EAB.

Ash logs with bark removed to reveal serpentine EAB galleries

Serpentine galleries under the bark of an ash log are a strong indicator of EAB infestation. Photo by M. Merchant, Texas A&M Agrilife. 

Exit holes 

Near the end of summer, the larvae develop into adults and emerge from the wood to fly away. They make holes shaped like the letter ‘D’ as they exit the wood. Other borers leave similar holes, so this is not a definitive sign of EAB. Still, please log and report any ‘D’-shaped exit holes you see so foresters can determine whether EAB is the cause. 

Ash log showing adult EAB ready to exit a 'D'-shaped hole in the wood.

A D-shaped exit hole with an adult Emerald Ash Borer ready to fly away. Photo by Deborah Miller, US Forest Service. 

Woodpeckers 

When a tree is infested with EAB, woodpeckers take the opportunity to get a quick snack. If your ash tree is seeing a lot of woodpecker activity, it could be a sign they are feeding on EAB. Further investigation would be warranted. 

a red-bellied woodpecker on a tree trunk

Red-bellied woodpeckers are the most common type in Austin, but any woodpecker we see might be feeding on EAB larvae. Image courtesy Ken Thomas. 

Branches dying 

Any of the above sign or symptoms of EAB might be present and still go unnoticed. Often, the first detections of EAB are found based on the overall tree condition. As the larvae destroy the water-conducting tissue, branches begin dying throughout the canopy. The higher branches tend to thin and die first. Later, the tree may send up thick clusters of new branch sprouts from the lower trunk and roots. A tree in this condition is probably too far gone to save, but awareness of the problem can help save nearby trees.

Ash tree showing symptoms of EAB infestation

Ash trees with thinning branches and profuse sprouts at the base may be reacting to EAB attack. Photo by Leah Bauer, USDA Forest Service. 

Unfortunately, this type of symptom can be caused by many problems besides EAB. For example, an extreme freeze in February 2021 caused similar symptoms in some ash trees. A qualified arborist can help you determine the cause of your tree’s decline and develop a good management strategy. 

Help With Science 

As you search for ash trees and Emerald Ash Borers, you will likely see some other insects, plants and animals. We hope you don’t find any Agrilus planipennis, but we think you will still have fun logging the organisms you find with iNaturalist. You can share any living things you see, but most do not cause any serious problems in our area. 

Next Steps 

Now that you’ve found your ash trees and you know how to identify EAB if you see it, it’s time to make a plan. Our next blog post, “Check Your Ash,” will help you decide whether to protect your tree against EAB or remove it.  

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This information is sponsored by the City of Austin. Learn more about trees and resources at the Tree Information Center! 

www.austintexas.gov/trees 

Sep 03, 2021 - 01:33 pm CDT

Trees provide important benefits to our community and are difficult to replace. It is important to keep them healthy. Perhaps the biggest challenge facing Austin trees is lack of water. When trees don’t receive the water that they need for a long period of time, they become stressed. Stressed trees are more prone to pests or diseases, and this leads to their decline and death.

 

When to water

Most trees need to be watered if we have not received at least one inch of rain for one week. This varies with tree age, tree species, and the type of soil.  In west Austin, the soil layer is thin and loses moisture quickly. In many parts of east Austin, the soil has more clay and might be over two feet deep. Clay soil tends to soak up water slowly, then hold it a long time. Some parts of Austin have gravelly or sandy soil that dries out quickly. The best way to know when to water is to dig into the soil and see if it’s dry. Once you get to know your soil, you will get better at predicting when your tree should be watered.

Photo of a tree with leaves browning and falling early due to drought.

At the end of a hot summer, this tree's leaves are turning brown and falling early. Proper irrigation could help it recover.

Since most tree roots are close to the surface, you only need to check for moisture in the top 6-12 inches of soil. If you find that the soil is dry or barely damp, you should water. At first, you might want to use a shovel so you can get a good look at where the soil is moist. With practice, you can learn this by feel using a screwdriver--it can easily be pushed into moist soil, while dry soil offers more resistance. For best results, water early in the morning to reduce loss from evaporation.

A photo of screwdrivers inserted into soil showing difference between wet and dry.

With practice, you can learn to test your soil with a screwdriver so you know when it's time to water.

How to water

Some watering methods are better than others. An occasional slow soaking is better than frequent, short bursts. Overhead sprinklers are simple and affordable, but tend to waste water. A licensed irrigator can install automatic systems to accommodate trees' special needs. Soaker hoses generally do the best job at getting the water into the soil. Add a layer of mulch over the hoses for even better results.

photo of a person pouring a bucket of water ono a tree's root zone

Trees are well adapted to receive water from the surface. Even pouring from a bucket helps. It's important to pour slowly enough to allow the water to soak in around the trees root zone.

Landscape with sprinklers spraying water across a landscape with trees.

Water sprayed over the surface of a landscape will benefit trees, but some is lost to evaporation. It's best to finish watering before the day heats up.

Tree trunk surrounded by rings of soaker hose

An array of soaker hoses allows water to seep into soil slowly. Cover it with a layer of mulch to reduce evaporation from the soil surface.

Photo of a tree surrounded by mulch with tape measure to demonstrate how to measure mulch depth.

Mulch works best in a layer three to four inches deep.

Where to water

Most tree roots live near the surface and spread outward up to three times the height of the tree. So, instead of watering at the base of the tree trunk, water should be spread throughout the root zone. Even if we can’t get water everywhere we want it, watering wherever possible will help the tree survive.

drawing of a landscape that shows the roots extending beyond the tree's branches.

              Most tree roots are not very deep in the soil, but they spread outward far beyond the branches.

How much water

We know to check our soil to see when to water, but how do we know when to turn off the water? It will vary based on the type of tree, the age of the tree, the soil type, and how you are applying the water. If you are using a soaker hose, let it run for 30 minutes, then check on how far the water actually moved down into the soil.  You can stop watering when water has soaked down 6 inches or more.

Tree age is important. For example:

  • A young tree won’t have as many roots and they won’t reach out as far as a mature one. Concentrate more water near the stem.
  • A tree that grew naturally will have wider, deeper roots than a transplant from a nursery. Water a larger area around the tree.
  • Newly planted trees might need to be watered twice a week or more. Check the container soil, not the surrounding lawn.
  • Check soil weekly for trees that are vulnerable. Give extra care to trees for the first three years after planting. Other at-risk trees include those with pests or disease and very old ones that have begun to decline.
  • Mature, established trees can usually manage without water for two to four weeks. Just be sure to water thoroughly when the soil becomes dry.
Resources:

You can get free mulch for your trees and plants from Austin Resource Recovery. Bring your own tools and containers.

You can learn about current watering restrictions and find your watering days at the Austin Water site.

 

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This information is sponsored by the City of Austin. Learn more about trees and resources at the Tree Information Center! 

www.austintexas.gov/trees 

Apr 20, 2021 - 12:38 pm CDT

Written by Pearl Morosky, 2020 Youth Forest Council Member

 

All the trees in Austin need care and attention to grow and flourish, but with 33 million trees in the city, it takes a community to give every tree the care it needs. To help solve this problem, different community groups, many of whom rely heavily on volunteers, have stepped up to care for Austin’s trees. One of the largest groups is the Austin Parks Foundation (APF). This local Austin nonprofit provides resources, programming, and funding for our parks, with support from the City.  

The City of Austin's Urban Forest Program provides funding to APF through the Urban Forest Grant, which supports different community groups and organizations in projects that support and grow our urban forest. An important part of the City’s effort to maintain and grow our urban forest is supporting the Austin Parks Foundation, which in turn helps to make sure Austin’s trees get the care they need.  

In 2019, the Urban Forest Grant gave just over $100,000 to APF to help with its efforts to care for the urban forest. In comparison, the calculated value of all volunteer time given through APF in 2019 comes out to over $500,000! With financial support of the Urban Forest Grant, in 2020, despite COVID-19 restrictions, APF successfully completed 112 tree-related projects across the city. APF serves as the parent organization of 120 Adopt-A-Park groups, giving them valuable connections to eager volunteers across the entire city. By partnering with APF, the City is able to maximize the value of the money put towards supporting our urban forest. 

The map below shows all the projects completed by APF with support from the Urban Forest Grant from 2018-2020. 

 

Austin map with orange markers showing caring projects and green markers showing growing projects

Explore the map.

 

One of the most important ways the City supports the Austin Parks Foundation is by helping facilitate It’s-My-Park Day, during which a great number of tree care projects are accomplished. Through the City’s support, APF provides tools, mulch, and volunteer coordination for this biannual day of service. This support helps to maximize the value of the time given by the 3,000+ volunteers on It’s-My-Park Day. 

Many of the projects accomplished by the City and APF, on It’s-My-Park Day and beyond, are related to tree mulching. While mulching may seem mundane, it can go a great length in caring for trees.  

Mulch: 

  • releases nutrients into the soil through decomposition 
  • protects soil from erosion 
  • minimizes loss of soil moisture 
  • regulates temperature 

The last three are especially important in Austin’s climate, as hot weather can dry out soil and negatively affect tree roots. APF has completed mulchings, with support from the Urban Forest Grant, all over Austin, in parks from Mayfield to Wells Branch to Dittmar. The Recycle & Reuse Drop-off Center provides free mulch (made from recovered yard trimmings) to Austinites interested in caring for trees on their property! 

 

Photo: A man and woman smile at the camera while holding shovels full of mulchPhoto: Two woman smile at the camera in front of a tree with mulch

 

The Urban Forest Grant also provides funds for larger-scale park renovations to promote growing and caring for the urban forest in that park. For example, when North Oaks park was renovated in 2019 to include updated play structures, the Urban Forest Grant provided $10,000 for tree planting. Such support allows parks to care for and grow our urban forest during renovation.  

All Austinites can be involved in preserving our urban forest! One of the most hands-on ways to do this is to get involved in a Park Adoption with the Austin Parks Foundation. Park Adopters help care for and maintain their neighborhood parks and help put on It’s-My-Park Day. For more information on adoptable parks, or to join an existing group, click visit the Adopt-A-Park wepage. The Austin Parks Foundation also offers lots of volunteer opportunities for individuals and families, many of which involve the urban forest. Volunteers are an invaluable resource for caring for our urban forest and allow Austin’s urban forest to keep on thriving! 

 


 

This blog post was written as a project of the 2020 Youth Forest Council. You can learn more about the program at www.austintexas.gov/youthforest.

 

Feb 12, 2021 - 10:30 am CST

Written by Antonia; October 23, 2020

One of the most exciting aspects of leaving for college, for me, was the fact that I would have so many new areas to explore. So, of course, I used the free time I had to look around campus and find all of the hidden, interesting places, both indoors and outdoors. Luckily, I made a friend who was also rather adventurous and we’d plan days to go out and see if we could find something new. From a strange, deserted basement with a room full of puppets to an old cemetery surrounded by trees, we definitely found some interesting stuff. 

Although I wasn’t with my friend when I filmed this tree, we did find it together behind one of the dorms on one of our adventures. From where I sat on a hill near the tree, gazing up at it as it towered over me, I could hear grade-school students practicing soccer at the school across the street and the dozens of cars that passed by on the busy road below. 

 


Stories Through Nature is a project of the 2020 Youth Forest Council. You can learn more about the program at www.austintexas.gov/youthforest.

Feb 10, 2021 - 10:20 am CST

Written by Edgar; November 2020

 

Midterms are one of the most stressful times as a college student. During stressful times, going to the park and listening to the wind blow through trees is therapeutic for me.  Losing myself in peaceful thoughts can help clear my mind, so that I can go back to daily life feeling more positive.

Can you guess the tree which these leaves belong to? Here is my guess.

 

    

 


 

Stories Through Nature is a project of the 2020 Youth Forest Council. You can learn more about the program at www.austintexas.gov/youthforest

 

Feb 08, 2021 - 09:39 am CST

Written by Evelyn; October 9, 2020

 

Ever since I was little, I’ve had a love for learning. Cousins and friends would question me as I learned the multiplication tables on weekends and had extra books for fun. Although it may look different today, my love for learning is still relevant. In my current writing seminar, I have been learning about disability studies. It’s really interesting to delve deep into a topic I had no experience in and learn how my identity and my position in society can affect disabled individuals. One of the assignments in my class is writing a paper on disability studies and another topic of my choosing. I chose green spaces and nature. After reading a novel (Feminist, Queer, Crip by Alison Kafer) and doing research, it’s consistently shown how disabled individuals have been marginalized from nature —  from the stereotypical “fit” body to assuming parks are dangerous to simply not extending opportunities. Studies have also shown that spending time in nature decreases stress levels and increases confidence. Before taking this class and participating in the Youth Forest Council internship, I assumed nature was accessible to everyone — it's nature! But time and time again, I have been exposed to the work we as a society still have to do in order to create equitable access to green spaces. What can you contribute to equity in nature? 

         

 

 


 

Stories Through Nature is a project of the 2020 Youth Forest Council. You can learn more about the program at www.austintexas.gov/youthforest.

 

Jan 14, 2021 - 04:22 pm CST

stories through nature

 

Written by Evelyn; October 1, 2020

 

Sometimes all one needs is some food for the soul. For me, spending time in nature solves that. Bike riding, hiking, or even sitting in my backyard on the trampoline as the sun sets. I am currently in a part of my life where a lot of things are changing. New doors are opening and I’m growing more curious about the world. The pandemic has caused a lot of last-minute planning, but having time to meditate helps. Feeling the breeze on my skin, the birds communicating with each other, leaves rustling. It all brings my head back down.

We all think about how nature needs us, but I think we need nature more.  

Can you guess what tree this leaf is from? My guess is here

 

nature map     nature blog map

 

greenery for the soul

 


 

Stories Through Nature is a project of the 2020 Youth Forest Council. You can learn more about the program at www.austintexas.gov/youthforest.

 

Jan 08, 2021 - 12:32 pm CST

Banner that says "Stories Through Nature: a project of the 2020 Youth Forest Council". The words are hand written and playful. The text is surrounded by illustrations of leaves.

Written by Antonia; August 26, 2020

For the last tree I would be filming in Austin, I decided to film the Ashe Juniper tree in my backyard. I’ve always loved Junipers, although I’m not entirely sure why, and it’s always been my favorite tree near my house. I’ve always watched it through my kitchen window while doing the dishes, hoping to catch sight of a cardinal or mockingbird landing on its branches. Such moments, though small, brought me a lot of happiness.  

As I sat in my backyard, beneath this tree, it began to sink in that I wouldn’t be at home for a while. Until then, I hadn’t really registered how far from home I would be and, while I didn’t feel scared about it, I felt a bit of shock regarding how big my next step in life would be. I used this moment to think about this, listening to the sound of wind chimes in the distance and birds in the trees around me.  

(Also, at one point, my neighbors’ chickens hopped over our fence and began exploring our backyard, which was very fun to watch).

 


Stories Through Nature is a project of the 2020 Youth Forest Council. You can learn more about the program at www.austintexas.gov/youthforest.

 

Dec 13, 2021 - 11:47 am CST

Ash tree with red and white warning symbolAlert! Tree emergency!

You may have seen our recent posts where we warned you about an invasive insect, Emerald Ash Borer (EAB). This pest could kill all our ash trees within a few years, so we need to prepare now! In the earlier posts, we encouraged you to help us find Ash trees and map them using iNaturalist. We hope you will also keep watch for signs of the insect in our area. Early detection is key to saving as many trees as possible. Now you should take a close look at the ash trees you found. You must decide if you want to protect them against the insect when it arrives. 

What Is Your Ash Worth?

The first step is to decide if the tree is worth saving. We hate to lose any of our trees, but sometimes removal is the best option. We would have to commit to years of expensive treatments to protect any ash tree against EAB. It often makes more sense to replace a weak tree with a more reliable species. Several factors might affect your decision.

In Austin, it was common to plant Arizona Ash in new developments around 50 years ago. The lifespan of an Arizona Ash is rarely much longer than this. In other words, these trees are nearing the end of their lives no matter what we do. Older trees also may have problems with decay and structure that make them likely to break when stressed. No matter what we do to care for them, they are likely to fail or die within a few years. 

Younger trees may still have some good years in them. Also, some ash species are less prone to the structural problems of Arizona ash. These are more likely to merit treatment. A qualified arborist can help you assess your trees and the associated risks.

Trunk of an ash tree showing decayed and splitting wood.

If your tree is in poor condition, you might choose to remove it instead of treating for EAB.

Save your ash!

After you consult with an arborist, you might decide to keep your trees. Next, you should prepare to have the trees treated. Trained professionals can inject a chemical into the tree which will then kill any insects that feed on it. You will need to repeat this treatment every 2-3 years, so it can get rather expensive--even more so for larger trees. Still, treatment is the only way we have found that is likely to be successful against EAB.

Unfortunately, a lot of our ash trees were damaged during the extreme freeze of February 2021. This damage may be hard to distinguish from EAB for the next few years. Some may have been so badly frozen that they will not recover. A qualified arborist can help you determine the cause of your tree’s decline and how to manage it.

Ash trunk being injected with insecticide

To preserve ash trees in the presence of EAB, we must treat them with a chemical insecticide. (photo courtesy Matthew Karst).

When to treat

Timing of these responses is tricky. If we treat now, the chemical may lose effectiveness before EAB arrives. Ideally, we will have lots of advance warning. If we see it coming, we should begin treating when the insect is within 10-20 miles from us. Unfortunately, we might not get such notice. Often, EAB is in a city for years before symptoms are severe enough to recognize. You should prepare for a rapid response.

If you intend to save your tree with chemical treatments, you would be wise to find qualified help now. Companies that treat for EAB are likely to be extremely busy in the first weeks after the insect arrives. If you already have a plan in place, you are more likely to be among the first to receive service.

Proactive removal

If you decide your tree is not worth the expense to save it, you might want to let it die naturally, then have it cut down. Unfortunately, this probably won’t be the best option. It’s a difficult decision, but an important one, so take the time to consider all factors.

With an EAB infestation, tree removals become far more hazardous and expensive. The borers weaken the wood dramatically. Trees begin to fall apart much more quickly than those that die from other causes. This is such a pronounced effect that climbing them is too dangerous. Experts recommend using mechanical lifts or other expensive equipment to remove ash trees killed by EAB. Companies with this equipment will be very busy once EAB is here. Proactive ash removal is likely to be much cheaper than waiting until a tree dies from EAB.

Aerial lift truck with bucket extended

Trees killed by EAB become very weak. They must be removed with expensive equipment.

When to remove

How do you know if it is time to remove your ash tree? You could cut the tree down any time before EAB arrives and have no problems related to the insect. Be sure the company you hire has liability insurance to protect you and your property. If you have doubts, don’t be afraid to copy the policy information and call the insurer directly to confirm.

If your tree is larger than 19” diameter at breast height, you must get a permit to remove it (per Austin's Land Development Code). The City Arborist will consider most residential ash trees “Dead, Diseased, Imminent Hazard.” In these cases, permit fees and remediation will not be required. You can start the permitting process at the City website.

Phased removal

If you have the budget, you might decide to take a phased approach. Have a company start removing the most extended, hazardous, or hard-to-reach parts now. Plant a replacement tree (not an ash) in the gap they create. This reduces risk in the short term while the new tree becomes established. You can remove the rest of the ash tree later.

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This information is sponsored by the City of Austin. Learn more about trees and resources at the Tree Information Center!

Nature in the City – Austin
Nov 17, 2021 - 04:17 pm CST

Ash tree with red and white warning symbol

Alert! Tree emergency!

You may have seen our recent post where we warned you about an invasive insect, Emerald Ash Borer (EAB). This pest could kill all our ash trees within a few years, so we need to prepare now! In the earlier post, we encouraged you to help us find Ash trees and map them using iNaturalist. While you’re working on that, we hope you will also keep watch for signs of the insect in our area. Early detection is key to saving as many trees as possible. A quick response will also help reduce the dangers to life and property that EAB-infected trees can cause.  

What is EAB? 

Emerald Ash Borer (Agrilus planipennis) is a beetle from Asia. It probably hitchhiked to the USA in a packing crate or other wood product around 2002. It causes only minor problems in its home environment, but it has no natural predators here. It reproduces rapidly and the population destroys trees within a few months. No ash trees can be expected to survive an attack of EAB without chemical treatments to protect them. Hundreds of millions of trees have been killed in the US since EAB arrived here. 

The beetle arrived in Michigan over twenty years ago and has since spread to 35 US states and 5 Canadian provinces. It was first found in Texas near the Louisiana border in 2016 and is now known to be in six Texas counties. We still have not found any of them in Austin, but a beetle or its eggs could arrive any day on a load of firewood or other cargo.  

Let’s learn what to look for so we can respond in a timely way. Then we can protect our best ash trees against EAB before it kills them. 

Shiny and Green 

The insect is small and easy to overlook. The most striking detail is the shiny, green shell that sometimes glitters gold, copper, or purple in sunlight. Its body is less than half an inch long and an eighth of an inch wide.  

Adult Emerald Ash Borers on a penny for size reference, exit holes visible.

Two adult Emerald Ash Borers with a penny for size reference. Note “D”-shaped exit holes to the left. Image courtesy newbruswicktoday.com 

When it flies, the green shell opens to reveal its bright, red body.

Adult EAB with wings spread to show red body underneath.

Adult Emerald Ash Borer with wings spread to reveal red body underneath. Image courtesy USDA-APHIS. 

If you see an adult EAB, please try to get a photo and report it. The iNaturalist app and website are one good place to record your find. You can also report it to Austin’s Urban Forester via 311, send an email, or contact the Texas A&M Forest Service

Larvae 

Adult beetles eat some leaves from our ash trees, but the larvae cause the real damage. The adult lays eggs on the bark in late spring. When they hatch, the larvae chew into the bark and begin eating the tender sapwood just beneath it. By the end of summer, the larvae may be as long as 1.5 inches.

EAB larva in an ash log with bark removed

EAB larvae chew tunnels through sapwood. This one is exposed in its tunnel because the bark has been removed. Image by Pennsylvania Department of Conservation and Natural Resources. 

Galleries 

We will keep our eyes open for adult beetles and larvae, but we are more likely to find the insect based on the tree’s reaction. EAB can feed on trees unnoticed for some time before symptoms appear. In a tree that has been attacked by EAB, we may see bark peeling off. There will be serpentine tunnels, or galleries, underneath. Even without seeing a larva, this is a strong sign we have found EAB.

Ash logs with bark removed to reveal serpentine EAB galleries

Serpentine galleries under the bark of an ash log are a strong indicator of EAB infestation. Photo by M. Merchant, Texas A&M Agrilife. 

Exit holes 

Near the end of summer, the larvae develop into adults and emerge from the wood to fly away. They make holes shaped like the letter ‘D’ as they exit the wood. Other borers leave similar holes, so this is not a definitive sign of EAB. Still, please log and report any ‘D’-shaped exit holes you see so foresters can determine whether EAB is the cause. 

Ash log showing adult EAB ready to exit a 'D'-shaped hole in the wood.

A D-shaped exit hole with an adult Emerald Ash Borer ready to fly away. Photo by Deborah Miller, US Forest Service. 

Woodpeckers 

When a tree is infested with EAB, woodpeckers take the opportunity to get a quick snack. If your ash tree is seeing a lot of woodpecker activity, it could be a sign they are feeding on EAB. Further investigation would be warranted. 

a red-bellied woodpecker on a tree trunk

Red-bellied woodpeckers are the most common type in Austin, but any woodpecker we see might be feeding on EAB larvae. Image courtesy Ken Thomas. 

Branches dying 

Any of the above sign or symptoms of EAB might be present and still go unnoticed. Often, the first detections of EAB are found based on the overall tree condition. As the larvae destroy the water-conducting tissue, branches begin dying throughout the canopy. The higher branches tend to thin and die first. Later, the tree may send up thick clusters of new branch sprouts from the lower trunk and roots. A tree in this condition is probably too far gone to save, but awareness of the problem can help save nearby trees.

Ash tree showing symptoms of EAB infestation

Ash trees with thinning branches and profuse sprouts at the base may be reacting to EAB attack. Photo by Leah Bauer, USDA Forest Service. 

Unfortunately, this type of symptom can be caused by many problems besides EAB. For example, an extreme freeze in February 2021 caused similar symptoms in some ash trees. A qualified arborist can help you determine the cause of your tree’s decline and develop a good management strategy. 

Help With Science 

As you search for ash trees and Emerald Ash Borers, you will likely see some other insects, plants and animals. We hope you don’t find any Agrilus planipennis, but we think you will still have fun logging the organisms you find with iNaturalist. You can share any living things you see, but most do not cause any serious problems in our area. 

Next Steps 

Now that you’ve found your ash trees and you know how to identify EAB if you see it, it’s time to make a plan. Our next blog post, “Check Your Ash,” will help you decide whether to protect your tree against EAB or remove it.  

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This information is sponsored by the City of Austin. Learn more about trees and resources at the Tree Information Center! 

www.austintexas.gov/trees 

Nature in the City – Austin
Sep 03, 2021 - 01:33 pm CDT

Trees provide important benefits to our community and are difficult to replace. It is important to keep them healthy. Perhaps the biggest challenge facing Austin trees is lack of water. When trees don’t receive the water that they need for a long period of time, they become stressed. Stressed trees are more prone to pests or diseases, and this leads to their decline and death.

 

When to water

Most trees need to be watered if we have not received at least one inch of rain for one week. This varies with tree age, tree species, and the type of soil.  In west Austin, the soil layer is thin and loses moisture quickly. In many parts of east Austin, the soil has more clay and might be over two feet deep. Clay soil tends to soak up water slowly, then hold it a long time. Some parts of Austin have gravelly or sandy soil that dries out quickly. The best way to know when to water is to dig into the soil and see if it’s dry. Once you get to know your soil, you will get better at predicting when your tree should be watered.

Photo of a tree with leaves browning and falling early due to drought.

At the end of a hot summer, this tree's leaves are turning brown and falling early. Proper irrigation could help it recover.

Since most tree roots are close to the surface, you only need to check for moisture in the top 6-12 inches of soil. If you find that the soil is dry or barely damp, you should water. At first, you might want to use a shovel so you can get a good look at where the soil is moist. With practice, you can learn this by feel using a screwdriver--it can easily be pushed into moist soil, while dry soil offers more resistance. For best results, water early in the morning to reduce loss from evaporation.

A photo of screwdrivers inserted into soil showing difference between wet and dry.

With practice, you can learn to test your soil with a screwdriver so you know when it's time to water.

How to water

Some watering methods are better than others. An occasional slow soaking is better than frequent, short bursts. Overhead sprinklers are simple and affordable, but tend to waste water. A licensed irrigator can install automatic systems to accommodate trees' special needs. Soaker hoses generally do the best job at getting the water into the soil. Add a layer of mulch over the hoses for even better results.

photo of a person pouring a bucket of water ono a tree's root zone

Trees are well adapted to receive water from the surface. Even pouring from a bucket helps. It's important to pour slowly enough to allow the water to soak in around the trees root zone.

Landscape with sprinklers spraying water across a landscape with trees.

Water sprayed over the surface of a landscape will benefit trees, but some is lost to evaporation. It's best to finish watering before the day heats up.

Tree trunk surrounded by rings of soaker hose

An array of soaker hoses allows water to seep into soil slowly. Cover it with a layer of mulch to reduce evaporation from the soil surface.

Photo of a tree surrounded by mulch with tape measure to demonstrate how to measure mulch depth.

Mulch works best in a layer three to four inches deep.

Where to water

Most tree roots live near the surface and spread outward up to three times the height of the tree. So, instead of watering at the base of the tree trunk, water should be spread throughout the root zone. Even if we can’t get water everywhere we want it, watering wherever possible will help the tree survive.

drawing of a landscape that shows the roots extending beyond the tree's branches.

              Most tree roots are not very deep in the soil, but they spread outward far beyond the branches.

How much water

We know to check our soil to see when to water, but how do we know when to turn off the water? It will vary based on the type of tree, the age of the tree, the soil type, and how you are applying the water. If you are using a soaker hose, let it run for 30 minutes, then check on how far the water actually moved down into the soil.  You can stop watering when water has soaked down 6 inches or more.

Tree age is important. For example:

  • A young tree won’t have as many roots and they won’t reach out as far as a mature one. Concentrate more water near the stem.
  • A tree that grew naturally will have wider, deeper roots than a transplant from a nursery. Water a larger area around the tree.
  • Newly planted trees might need to be watered twice a week or more. Check the container soil, not the surrounding lawn.
  • Check soil weekly for trees that are vulnerable. Give extra care to trees for the first three years after planting. Other at-risk trees include those with pests or disease and very old ones that have begun to decline.
  • Mature, established trees can usually manage without water for two to four weeks. Just be sure to water thoroughly when the soil becomes dry.
Resources:

You can get free mulch for your trees and plants from Austin Resource Recovery. Bring your own tools and containers.

You can learn about current watering restrictions and find your watering days at the Austin Water site.

 

Think Trees Logo

This information is sponsored by the City of Austin. Learn more about trees and resources at the Tree Information Center! 

www.austintexas.gov/trees 

Nature in the City – Austin
Apr 20, 2021 - 12:38 pm CDT

Written by Pearl Morosky, 2020 Youth Forest Council Member

 

All the trees in Austin need care and attention to grow and flourish, but with 33 million trees in the city, it takes a community to give every tree the care it needs. To help solve this problem, different community groups, many of whom rely heavily on volunteers, have stepped up to care for Austin’s trees. One of the largest groups is the Austin Parks Foundation (APF). This local Austin nonprofit provides resources, programming, and funding for our parks, with support from the City.  

The City of Austin's Urban Forest Program provides funding to APF through the Urban Forest Grant, which supports different community groups and organizations in projects that support and grow our urban forest. An important part of the City’s effort to maintain and grow our urban forest is supporting the Austin Parks Foundation, which in turn helps to make sure Austin’s trees get the care they need.  

In 2019, the Urban Forest Grant gave just over $100,000 to APF to help with its efforts to care for the urban forest. In comparison, the calculated value of all volunteer time given through APF in 2019 comes out to over $500,000! With financial support of the Urban Forest Grant, in 2020, despite COVID-19 restrictions, APF successfully completed 112 tree-related projects across the city. APF serves as the parent organization of 120 Adopt-A-Park groups, giving them valuable connections to eager volunteers across the entire city. By partnering with APF, the City is able to maximize the value of the money put towards supporting our urban forest. 

The map below shows all the projects completed by APF with support from the Urban Forest Grant from 2018-2020. 

 

Austin map with orange markers showing caring projects and green markers showing growing projects

Explore the map.

 

One of the most important ways the City supports the Austin Parks Foundation is by helping facilitate It’s-My-Park Day, during which a great number of tree care projects are accomplished. Through the City’s support, APF provides tools, mulch, and volunteer coordination for this biannual day of service. This support helps to maximize the value of the time given by the 3,000+ volunteers on It’s-My-Park Day. 

Many of the projects accomplished by the City and APF, on It’s-My-Park Day and beyond, are related to tree mulching. While mulching may seem mundane, it can go a great length in caring for trees.  

Mulch: 

  • releases nutrients into the soil through decomposition 
  • protects soil from erosion 
  • minimizes loss of soil moisture 
  • regulates temperature 

The last three are especially important in Austin’s climate, as hot weather can dry out soil and negatively affect tree roots. APF has completed mulchings, with support from the Urban Forest Grant, all over Austin, in parks from Mayfield to Wells Branch to Dittmar. The Recycle & Reuse Drop-off Center provides free mulch (made from recovered yard trimmings) to Austinites interested in caring for trees on their property! 

 

Photo: A man and woman smile at the camera while holding shovels full of mulchPhoto: Two woman smile at the camera in front of a tree with mulch

 

The Urban Forest Grant also provides funds for larger-scale park renovations to promote growing and caring for the urban forest in that park. For example, when North Oaks park was renovated in 2019 to include updated play structures, the Urban Forest Grant provided $10,000 for tree planting. Such support allows parks to care for and grow our urban forest during renovation.  

All Austinites can be involved in preserving our urban forest! One of the most hands-on ways to do this is to get involved in a Park Adoption with the Austin Parks Foundation. Park Adopters help care for and maintain their neighborhood parks and help put on It’s-My-Park Day. For more information on adoptable parks, or to join an existing group, click visit the Adopt-A-Park wepage. The Austin Parks Foundation also offers lots of volunteer opportunities for individuals and families, many of which involve the urban forest. Volunteers are an invaluable resource for caring for our urban forest and allow Austin’s urban forest to keep on thriving! 

 


 

This blog post was written as a project of the 2020 Youth Forest Council. You can learn more about the program at www.austintexas.gov/youthforest.

 

Nature in the City – Austin
Feb 12, 2021 - 10:30 am CST

Written by Antonia; October 23, 2020

One of the most exciting aspects of leaving for college, for me, was the fact that I would have so many new areas to explore. So, of course, I used the free time I had to look around campus and find all of the hidden, interesting places, both indoors and outdoors. Luckily, I made a friend who was also rather adventurous and we’d plan days to go out and see if we could find something new. From a strange, deserted basement with a room full of puppets to an old cemetery surrounded by trees, we definitely found some interesting stuff. 

Although I wasn’t with my friend when I filmed this tree, we did find it together behind one of the dorms on one of our adventures. From where I sat on a hill near the tree, gazing up at it as it towered over me, I could hear grade-school students practicing soccer at the school across the street and the dozens of cars that passed by on the busy road below. 

 


Stories Through Nature is a project of the 2020 Youth Forest Council. You can learn more about the program at www.austintexas.gov/youthforest.

Nature in the City – Austin
Feb 10, 2021 - 10:20 am CST

Written by Edgar; November 2020

 

Midterms are one of the most stressful times as a college student. During stressful times, going to the park and listening to the wind blow through trees is therapeutic for me.  Losing myself in peaceful thoughts can help clear my mind, so that I can go back to daily life feeling more positive.

Can you guess the tree which these leaves belong to? Here is my guess.

 

    

 


 

Stories Through Nature is a project of the 2020 Youth Forest Council. You can learn more about the program at www.austintexas.gov/youthforest

 

Nature in the City – Austin
Feb 08, 2021 - 09:39 am CST

Written by Evelyn; October 9, 2020

 

Ever since I was little, I’ve had a love for learning. Cousins and friends would question me as I learned the multiplication tables on weekends and had extra books for fun. Although it may look different today, my love for learning is still relevant. In my current writing seminar, I have been learning about disability studies. It’s really interesting to delve deep into a topic I had no experience in and learn how my identity and my position in society can affect disabled individuals. One of the assignments in my class is writing a paper on disability studies and another topic of my choosing. I chose green spaces and nature. After reading a novel (Feminist, Queer, Crip by Alison Kafer) and doing research, it’s consistently shown how disabled individuals have been marginalized from nature —  from the stereotypical “fit” body to assuming parks are dangerous to simply not extending opportunities. Studies have also shown that spending time in nature decreases stress levels and increases confidence. Before taking this class and participating in the Youth Forest Council internship, I assumed nature was accessible to everyone — it's nature! But time and time again, I have been exposed to the work we as a society still have to do in order to create equitable access to green spaces. What can you contribute to equity in nature? 

         

 

 


 

Stories Through Nature is a project of the 2020 Youth Forest Council. You can learn more about the program at www.austintexas.gov/youthforest.

 

Nature in the City – Austin
Jan 14, 2021 - 04:22 pm CST

stories through nature

 

Written by Evelyn; October 1, 2020

 

Sometimes all one needs is some food for the soul. For me, spending time in nature solves that. Bike riding, hiking, or even sitting in my backyard on the trampoline as the sun sets. I am currently in a part of my life where a lot of things are changing. New doors are opening and I’m growing more curious about the world. The pandemic has caused a lot of last-minute planning, but having time to meditate helps. Feeling the breeze on my skin, the birds communicating with each other, leaves rustling. It all brings my head back down.

We all think about how nature needs us, but I think we need nature more.  

Can you guess what tree this leaf is from? My guess is here

 

nature map     nature blog map

 

greenery for the soul

 


 

Stories Through Nature is a project of the 2020 Youth Forest Council. You can learn more about the program at www.austintexas.gov/youthforest.

 

Nature in the City – Austin
Jan 08, 2021 - 12:32 pm CST

Banner that says "Stories Through Nature: a project of the 2020 Youth Forest Council". The words are hand written and playful. The text is surrounded by illustrations of leaves.

Written by Antonia; August 26, 2020

For the last tree I would be filming in Austin, I decided to film the Ashe Juniper tree in my backyard. I’ve always loved Junipers, although I’m not entirely sure why, and it’s always been my favorite tree near my house. I’ve always watched it through my kitchen window while doing the dishes, hoping to catch sight of a cardinal or mockingbird landing on its branches. Such moments, though small, brought me a lot of happiness.  

As I sat in my backyard, beneath this tree, it began to sink in that I wouldn’t be at home for a while. Until then, I hadn’t really registered how far from home I would be and, while I didn’t feel scared about it, I felt a bit of shock regarding how big my next step in life would be. I used this moment to think about this, listening to the sound of wind chimes in the distance and birds in the trees around me.  

(Also, at one point, my neighbors’ chickens hopped over our fence and began exploring our backyard, which was very fun to watch).

 


Stories Through Nature is a project of the 2020 Youth Forest Council. You can learn more about the program at www.austintexas.gov/youthforest.

 

Nature in the City – Austin