What is Drilling Holes in My Trees?

What is Drilling Holes in My Trees?

They are often very prevalent on trees in our area; a strange string of shallow holes drilled in the bark of a tree. Often this is oozing sap, especially on pines and hardwoods with heavy sap flow, and more holes keep appearing as the sap dries up in others. I get calls and questions all the time about this strange phenomenon and what can be done about it. The calls are usually from homeowners with a prized backyard tree, but I get calls from farmers with orchard crops and other settings as well. What is causing this strange attack on these trees? What drills near perfect holes just into the sapwood of a tree? The answer is a bird of all things; and in particular the yellowbellied sapsucker (Sphyrapicus varius). This small to mid-sized bird is in the woodpecker family and has the peculiar diet of feeding on sweet and nourishing tree sap; as well as small insects attracted to and trapped into the sap. This little native bird drills and taps trees for sweet sap. Much like we humans do with maple trees up north for syrup production. They then visit their trees and drink the sap until the tap dries up and then drill another hole. This pattern of feeding leaves this banding of holes drilled on the tree, and they drill deep enough that it will be visible for quite a long time often permanently.

Yellowbellied Sapsucker damage on an American Sycamore-Walton County, FL Photo Credit: Ian Stone

The biggest question most people want answered, beside what is doing/causing this, is will this hurt the tree? The best answer to that is mostly no, but with all things tree related it depends. On young and smaller trees, particularly newly planted ones, the feeding can stress the tree and can cause some issues. The biggest risk is that if the sapsucker drills in a complete ring around the trunk, something more common on smaller trees, they could cause the tree to be girdled and killed. Another issue is that their feeding can attract pests and disease, such as bark and wood boring beetles along with some fungal infections of the open wounds. These pest and diseases may then go on to cause severe damage and death, especially if the tree is stressed by drought or other environmental factors. Ultimately, the feeding of the yellowbellied sapsucker rarely kills or severely damages trees by itself. Most of the time it just causes unsightly damage, and the bark damage and subsequent healing over can cause an unsightly area of bark. This is especially true on thin barked trees that have smooth bark, such as beech, magnolia, and birch.

You are probably wondering how to prevent this damage in the first place or stop it once a sapsucker takes a liking to your tree. The best thing to do is to make some changes in your landscape to prevent attracting sapsuckers and/or scare them away if they are in the area. Your first step is to learn to identify the yellowbellied sapsucker, so you can tell if they are in the area. Yellowbellied sapsuckers are a woodpecker and to many they look like several of our other small woodpeckers such as the downy, red-cockaded, and possibly even the red bellied. They look the most like a slightly larger downy woodpecker with more red on their heads. Males are the most brightly colored and have a read crown and throat patch, while females have the red crown only. The back and wings are black and white, and have somewhat of a ladder appearance on the back. They are smaller birds, around 7-8 in. in length, similar in size to a robin or cardinal. They cling to the bark and shuffle up and down the tree like other woodpeckers. The namesake yellow belly is faint and difficult to see at a distance without binoculars or other aids

Yellowbellied Sapsucker (Sphyrapicus varius) side profile Photo Credit:  Johnny N. Dell, Bugwood.org

If you notice yellowbellied sapsuckers in your area, you can watch them to see which trees they seem attracted to. Once you identify the portion of your yard they seem to like; you can put up windsocks or predatory statues to scare them away. This is the most effective method to keep these somewhat pesky birds out of an area and stop the tree damage. It also does not harm the birds or any other wildlife, though it may scare away birds that you would like to stick around. You may see some information about putting up hardware cloth or metal sheeting around the trunk of the tree. This is not a good method and often it does not stop the sapsuckers, who simply find another unguarded portion of the tree or work around the exclusion device. Using hardware cloth or sheeting can also damage the tree worse than the sapsucker’s feeding activity, and if not properly installed and consistently loosened they can even girdle and kill a tree. If you are having trouble with the interesting but pesky birds, use the scare away method consistently until they leave the area. If they believe predators are in the area and regularly startled while feeding they usually leave for a better feeding area pretty quickly.   

The Summer Stress is Starting to Show in Trees

The Summer Stress is Starting to Show in Trees

It has been a hard summer climate wise and as we go into fall it is nice to start getting some relief from the heat. As the heat tones down, we are still facing a drought, which is not as severe as areas to our west but is still significant across much of the Panhandle. In our tree cover, the stress from the harsh summer this year is starting to show. You can see it in trees around the area, and it particularly seems to affect certain trees and conditions more than others. Where you are starting to see it most is in our ever-present pines, which make up the majority of our forest and tree cover in our region. If you keep a look out you may notice some pines in the areas with yellowing or brown needles or that are losing their needles. Those are clear signs of a possible bark beetle attack, which is a common issue when pines are stressed or damaged. Trees planted in the last year that are not yet fully established often show stress in a hot dry summer like this year. Even older and well-established trees in areas are showing some signs of stress from the hot dry conditions we have had this summer.  Some trees are less adapted to dryer areas and when planted off site can experience more stress in dry conditions. If you look around across the Panhandle right now you can see clear signs of stress in some trees. It becomes more evident in late summer and early fall as the accumulated stressors of summer push trees into physiological conditions that cause stress responses. The big question is what to do if you notice a landscape tree that is exhibiting signs of stress, particularly drought stress.

Pine damaged by construction equipment. Barking injuries like this can encourage bark beetle attacks. Photo Credit: Ian Stone

For pines the issue is likely to be bark beetles, of which there are several types. All pine bark beetles are native to our area and the degree of damage they do varies by species and conditions. The issue with stressed trees is that most bark beetles attack those trees. When a hot dry summer occurs bark beetle activity increases as the stressed trees become less able to fend off attacks by these beetles. Unfortunately, when bark beetles attack a pine in an area the best answer is prompt removal and disposal of the infected tree material. To protect high value trees in an area where bark beetles are active there are some injection pesticides that can prevent infestation, but once a tree has been infested and begun to show symptoms little can be done to bring it back. When bark beetles attack a stressed pine, most are effectively finishing off a tree that may have died regardless. The key is to prevent them from spreading to other pines in the area or attracting them to a stressed tree in an area. With trees already stressed in our area the big prevention option is not to damage or stress any pines already on the landscape. Most pine bark beetles are attracted to trees by chemicals in pitch and resin given off by wounds or damage. Often the stress from new landscaping projects or construction around pines can cause several to succumb to bark beetles. Your best prevention is to keep equipment well away from the tree and avoid damaging or injuring the tree, especially scraping areas of bark off. Larger and older trees can be vulnerable, as well as overcrowded trees that are too dense or overtopped by others. As the cooler weather approaches bark beetle activity should decrease along with the risk of losing a pine to these pests.

Recently constructed sidewalk. Construction activities extended well into the root zone of the tree, which can cause stress and damage. Photo Credit; Ian Stone

For other trees there are additional precautions that can be taken to lessen the potential that a tree will succumb to drought and other stress. Newly planted trees or those established in the last several years are particularly at risk and should be watered regularly during this dry period. Until rains return, a good method of slowly applying water deeply to the root zone is best. Properly applied mulch can help keep the soil cooler and moist around a newly planted tree. Drip irrigation, soaker hoses, and similar methods are best, and a method that specifically applies water slowly to the tree’s root zone gives the best results. Watering your lawn does not supply sufficient water to landscape trees, especially in drought conditions. Lawn irrigation is designed to apply irrigation needed to the top portion of the soil that is available to the grass. Trees have completely different requirements and need different watering methods and amounts. If you don’t have dedicated irrigation available and you have a tree that needs water, you can use irrigation donuts or bags. These are often a good solution for a tree that needs watering temporarily. Once a tree is well established it usually can withstand even severe drought, but during the establishment phase paying attention to water needs is critical in a summer drought like we have had.

Large established trees are also not immune from the heat and dry conditions that have plagued the Panhandle this summer. Usually when conditions change these trees recover but may abort some branches or exhibit some leaf drop while stressed. Leaf drop is a phenomenon that can occur when deciduous trees are stressed. It is a method of conserving water needs by reducing the leaf demand. Usually, the tree will recover and leaf out again fine next year. A tree may abort some branches or have some branch tips die back to make it through a rough period. Trees that are overcrowded, overtopped, or have other issues are the most at risk from environmental stress. This is why good tree selection along with proper tree care and maintenance is essential. When a hot dry summer like we have had comes along well cared for and maintained trees do best. Trees that prefer more moisture like bald cypress, red maple, sycamore, and some oaks can be planted in dryer sites, but when a severe drought comes along they often don’t have the ability to handle the moisture stress that trees adapted to dryer sites can. This is why site selection is so important, it is when we have extreme conditions that off site plantings typically suffer the worst and those can be larger more established trees.

With the cool weather hopefully we will get a reprieve and some rain soon. Given that fall is one of our dryer periods it may be likely that drought conditions could persist until early winter. Good care and tree maintenance is essential to getting your trees through stressful periods like this summer. For younger trees watering and care is essential while they get established. For older established trees avoid doing any construction or other disturbing activities around them until conditions improve. If you have trees that are exhibiting signs of decline or pest attacks call your local extension office or Florida Forest Service County Forester office. With any luck, colder weather with winter rains will be here soon and trees in our area will recover over the dormant period.

This Heat Really Makes You Appreciate a Shade Tree

This Heat Really Makes You Appreciate a Shade Tree

If there is anything that is more refreshing than the cool shade of a tree on a hot August afternoon, I cannot quite think of it. Here on the Gulf Coast, the thought of the heat in the “Dog Days of Summer” conjures up images of the dogs lying by their owners’ rocking chairs on the veranda – shaded of course by the majestic live oaks out front. If you ever observe older homes in our region, they usually have large established shade trees to shade the house most of the day. In the days before air conditioning, I imagine a world without shade would be intolerable, nigh unlivable. If you have ever had to work on an asphalt parking lot or roof on a 100+ degree August day with no shade, you fully understand the term “heat island”. The steam rising off the same parking lot later after a passing shower or thunderstorm reinforces how hot that surface is.

Man walking a trail in Oak Hammock. UF/IFAS Photo: Thomas Wright.

These past few weeks the oppressive heat has made anything outside unbearable, especially in the heat of the afternoon. You can quickly understand why old farmers in our area worked from sunup to about 10 a.m. or so, then did lighter work in shaded areas or inside. They would go back out and work hard in the cool of the evening too, but you seldom saw anyone out in the open fields during the mid-day heat if it were avoidable. A shade tree in the pasture or up at the house was a welcomed oasis and favorite lunch spot. Going back in the air conditioning just caused you to have more trouble acclimating to the heat and could even cause medical problems if you we very hot and suddenly went into very cool air conditioning. I remember these summer patterns well growing up on the Gulf Coast, and still follow them when doing forestry field work. Being under a closed forest canopy was like being in air conditioning compared to the open sun of a logging deck or pasture. The shade of a tree or a forest canopy offered an amazing relief from the blazing August heat and humidity.

It is impossible to stress enough the importance of individual shade trees and tree cover to our urban areas. Imagine our towns and cities devoid of trees! Imagine Tallahassee without its canopy roads, themselves sort of an early cooling effort for travelers. Without these trees it would make these heat waves, as oppressive as they are already, downright scorching and close to unlivable. If you are doing any gardening or other outdoor activity during these hot days, it is highly likely you seek out a shady area to be in. As that shade moves with the sun through the day it is equally likely that you relocate and follow it as it moves. If you have a neighbor that has no tree cover and shade on their house, and you are on good and friendly terms, ask to compare power bills with them. Odds are their power bill is noticeably higher because they do not have the shade of trees. With all the important features our urban forest provides, we must realize that our trees and the urban forest they form are critical to our urban ecosystem we live in. Yes, I said urban ecosystem; we must remember that we are part of nature too and even though we have altered it to our needs, our urban environment is part of our ecosystem. Trees are the backbone of that here on the Gulf Coast and our cities show it. Gulf Coast cities generally have extensive tree cover, despite our disturbances from Hurricanes.

So, what do these shade trees and urban forests really do for us in terms of actual measurable data? We know from just walking under a tree on a 100+ degree day we can feel the difference but what does it equate to. A study published in the Journal of Forestry in 2018 found that an estimated 5.5 billion urban trees provided an estimated $5.4 billion in energy reduction alone (Nowak and Greenfield 2018). This same study found that Florida was the state with the highest annual urban forestry value with an estimated annual value of $1.9 billion. Those are some impressive numbers and help put the value of urban forests into some monetary terms, but this is just one study. Professionals studying urban forests and their benefits are constantly finding out more on just how valuable our urban tree cover is. A UF-IFAS EDIS publication in 2020 helped to further characterize our urban forests across the state. Urban areas in the Northern part of the state had the highest percentage of canopy cover, with our local Okaloosa-Fort Walton-Destin area being the highest at 74.4% (McLean et al. 2020). Our local Panhandle metropolitan areas all had high canopy cover in the 50% or higher range. That is good news for Panhandle urban areas as this tree cover helps improve quality of life in these areas.

The benefits provided by urban forest cover are not just confined to shade, cooling, and reduced energy use. We get other major benefits from our urban forest and tree cover. The same 2020 UF-IFAS study found that in Florida’s urban areas, trees remove 600,000 tons of air pollutants through their canopies, which results in $605 million in health care savings related to air pollution. Urban tree cover also prevents stormwater runoff into our waterbodies. The study found that Florida’s urban forest cover prevents 50 billion gallons of stormwater runoff, which results in a $451 million saving from avoided stormwater treatment. Those benefits would not be possible without our urban trees. Once you see the numbers, it is clear how our urban forest provides us with so many benefits we rarely see or consider.

When you walk under the shade of a tree or under a forest canopy on these scorching summer days you get an instant reminder of the benefit of that tree cover. The cool relief from the sun and heat is just one of the many benefits our trees and urban forests provide. Trees are one of our favorite parts of the landscape for many reasons and studies that quantify these benefits put in real term just how critical our urban forests are to us. Our tree cover helps clean our air and capture stormwater in our summer downpours.  As our communities grow and expand, we need to be sure to preserve the trees we have and plant new ones as the need arises. By keeping our urban forest cover intact, we can enjoy the cool shade and all the other benefits our urban trees provide.

References and further reading:

Nowak, David J; Greenfield, Eric J. 2018. US Urban Forest Statistics, Values, and Projections. Journal of Forestry. 116(2): 164-177.

McLean, Drew C., Andrew Koeser, Deborah R. Hilbert, Shawn Landry, Amr Abd-Elrahman, Katie Britt, Mary Lusk, Michael Andreu, and Robert Northrop. 2020. “Florida’s Urban Forest: A Valuation of Benefits: ENH1331/EP595, 11/2020”. EDIS 2020 (6). https://doi.org/10.32473/edis-ep595-2020. ENH1331/EP595: Florida’s Urban Forest: A Valuation of Benefits (ufl.edu)

What To Do About “Hangers” In Your Tree?  

What To Do About “Hangers” In Your Tree?  

Tree with dead “hangers” from recent windstorms in the Panhandle. These dead broken limbs should be assessed and removed accordingly. Photo Credit: Ian Stone

Recently our area has experienced multiple severe wind events. You may have noticed some light to moderate damage to some of the trees in your yard. You may have even experienced severe damage or a complete failure of a tree on your or a neighbor’s property. While a complete failure or severe damage pose obvious hazards and need removal, it is the more minor to moderate damage that often raises questions on how to address the issue. Hanging broken branches are often called “Hangers” in forestry or tree care circles. These are often smaller to mid-sized branches which have partially broken off but are still lodged in the tree. After several weeks to a month the foliage starts to die and turn brown, and these “hangers” become obvious in trees that received damage. How do you assess these and when should you get a professional involved? Do they pose a potential health issue if not removed?

These broken limbs are becoming quite noticeable as they die and turn brown. It is important to make good decisions on how to handle these hanging dead branches and how to maintain your tree. Often these hangers are more unsightly than anything else, especially if they are small. Larger ones may pose a risk of damage or injury if they are located over a structure or may fall in an area frequented by people. Most of these hangers will break and dislodge over time, especially in wind events. You should consider the risk posed by the hanging limb, the difficulty and cost of addressing it, and the risk posed by the limb falling. For trees that got noticeable damage with several larger limbs broken, having some repair and rejuvenation pruning done is often good for tree health. You may be able to address some issues yourself if you are handy with a pole pruner and the broken limb is in reach. Anyone attempting even light tree work should be aware of risks posed by falling limbs and use of pole saws. Remember to never attempt to climb trees yourself or perform tree trimming from a ladder or height, as this is fundamentally unsafe. Even limbs which may be safely reached from the ground with a pole pruner can pose risks of injury. If you are attempting to remove some of these hangers with a pole pruner, be very cautious and use good safety techniques. You need to make sure the branch has a landing zone, and you are well clear of it when using a pole saw or pruner. Be aware of vines and other entanglements, and do not work around or within the right of way of electrical or other lines. Larger limbs and those not reachable from the ground should be considered outside the scope of homeowners and left to professionals.

Here is a quick reference guide for how to size up any broken or damaged limbs in your tree and address the situation

  1. Small branches and branch tips with a diameter of the broken branch is 1 inch or less and the branch is hanging or lodged. These size hangers pose little risk and are mostly unsightly. They should fall out of the tree on their own over time. These may be trimmed out slightly behind the break of those within reach of a pole pruner.
  2. Small to Medium branches-1-3 inches in diameter. The branch has partially broken or has completely broken and is lodged in another branch. Branches this size can do some light to moderate damage if they fall on a roof, fence, or other structure. If the branch overhangs areas where people or pets frequent it could cause injuries if it fails. If the branch does not pose a hazard or danger it should dislodge on its own over time. Consider removing these if they pose a risk. They can be removed from the ground with a pole pruner or pole saw but be very cautious as branches this size can easily injure someone that is in the fall zone. Consult a professional if a lift or climbing is required.
  3. Large Canopy Branches 3 inches and larger. These are significant branches and can hold a significant amount of weight. If they are partially broken, hung, or lodged in the tree they may come out at any time and do significant damage or cause injury. These branches are beyond the tools and scope of homeowners, and the damage may require some recovery pruning to keep the tree healthy. Consult with a professional and consider having the damage removed and tree properly trimmed.
  4. Main Branch and Trunk Failures- This is significant damage to the tree which can make it unsound or susceptible to disease in the future. If large main branches have failed, the top has completely failed, or part of the trunk has cracked or split from the damage; major damage has occurred and the tree may not recover. If your tree has suffered this level of damage consult a professional with a tree service and have a certified arborist examine the tree.

It can be hard to tell from the ground what level of damage a tree sustained until the brown foliage appears past the break. Once you can identify what type of damage occurred you can better determine what action is needed. For small branches it may be best just to wait for them to come out naturally or prune them out if this can be done safely with a pole pruner. For larger branches or more severe damage a professional is the best bet. For those hangers that pose a risk to structures or people in an area removal is best, as these could fall at any time and cause damage or injury. Remember never to attempt tree work yourself especially if it involves climbing or working from heights. You can find a certified arborist at www.treesaregood.org to address large limbs and significant damage. A good arborist can help you rehabilitate a tree that has had only moderate damage from a storm. If you are unsure of where to start with a tree that has wind damage, consult your local extension office for some advice.

Should I Trim or Remove My Tree? You May Want to Consult an Arborist

Should I Trim or Remove My Tree? You May Want to Consult an Arborist

It is the time of year when we get reminded that we have just entered Hurricane season here on the Gulf Coast. Ideally you will have already done your tree maintenance and health checks around your home, but if you have not you can still get a tree care professional out to look at your trees. Maintaining your trees is an important part of storm preparedness. Keeping trees trimmed and in good health ensures that tree risks are minimized during the storm season. Even with proper pruning and maintenance some trees pose a risk due to location, poor structure, or disease. Having a professional assess your tree/trees and come up with a maintenance plan can help you avoid costly damage and keep your tree in good condition.

In this file photo released by UF’s Institute of Food and Agricultural Sciences, Associate Dean for Research Mary Duryea and Ed Gilman, a UF urban horticulture professor, look over their recently published booklet that gives tips on how to prevent storm damage to urban trees.  The booklet is free and available on the Internet or at any county extension office.

Trees are a major part of our landscape on the Gulf Coast, especially in our urban areas. They provide so many benefits to the landscape and are often the centerpiece of yards and parks in our urban areas. Without trees we lose the shade and cooling benefits a tree provides, have less habitat for birds and other wildlife, and loose aesthetic values that come with a majestic tree. Trees take a long time to grow and develop as well, so a large well-developed tree is not easily replaced. This naturally leads to a question many people find themselves facing. How do I preserve trees I want but minimize risk to my home and structures? The answer to this question is to assess the condition of the tree, the risk it may pose, and decide on the proper tree maintenance accordingly.

Lots of things go into determining what to do with a tree. The first thing to consider is location of the tree and its limbs. If the tree and its limbs are close to your home, you must consider how to maintain the tree in such a way that risks are minimized. If the tree has structural and/or health problems, you must factor in how these conditions affect the stability and health of a tree. The tree species also determines how it will need to be maintained as well as how stable it is in a wind event. All of these factors play into how to maintain the trees on your landscape, or if the tree poses an unacceptable risk, when to remove trees that may be in decline or present a hazard.

The best course of action is to consult with a tree care professional and develop a tree maintenance plan. Make sure you select a tree care professional with good qualifications, background, and insurance. The top professional credential in tree care is the International Society of Arboriculture’s (ISA) Certified Arborist. You can search for a Certified Arborist in your area on the ISA Website, Find an Arborist (treesaregood.org). For trees that you are concerned about from a risk perspective consider getting a Tree Risk Assessment. Certain Certified Arborists carry a Tree Risk Assessment Qualification which is a specialty qualification specifically to assess the risk a tree poses. By having your trees examined by an arborist you can make an informed decision on maintaining your landscape trees. For trees that are in good health and are species that do well in high winds, proper maintenance and pruning will assist in keeping the tree in good condition. For trees with health or structural problems or that are species that do poorly in high winds, removal may be needed.

There is no one size fits all solution to tree maintenance and tree risk, but with proper assessment and tree care you can be confident you are making the correct decision. Putting off tree care and assessment is when problems occur. Consulting with an arborist and developing a tree care plan with clear timelines and practices is your best option to maintain your trees and avoid issues with high-risk trees. As painful as it may be, for high-risk trees removal and replacement may be the best option. By consulting with a tree care professional, such as an arborist, you can know your tree conditions and the associated risks and options. With this information in hand, you can make well informed decisions that match your tree health and risk management goals.    

References and Further Reading:

UF/IFAS Gardening Solutions Webpage: Preparing Trees For Hurricanes Link: Preparing Trees for Hurricanes – Gardening Solutions – University of Florida, Institute of Food and Agricultural Sciences (ufl.edu)

For Information on Recognizing Tree Health and Risk Issues:

McLean, D.C., A.K. Koeser, R.J. Northrop, and G. Hasing Is My Tree Safe? Recognizing Conditions That Increase The Likelihood of Tree Failure Publication# ENH1246  Gainesville: University of Florida Institute of Food and Agricultural Sciences ENH1246/EP507: Is my tree safe? Recognizing Conditions that Increase the Likelihood of Tree Failure (ufl.edu)

For information on tree species and their stability in wind:

Dureya, M.L. and E. Kampf Selecting Coastal Plain Species for Wind Resistance PUBLICATION #FOR119 Gainesville: University of Florida Institute of Food and Agricultural Sciences FOR119/FR174: Selecting Coastal Plain Species for Wind Resistance (ufl.edu)