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Author: Burkholder PHC

Callery Pear Tree Invasive Species

Callery pear trees (Pyrus calleryana), native to China and Vietnam, have been popular ornamental trees for almost 200 years. These trees were introduced to the United States in the 1800s and are often planted along streets and sidewalks because of their attractive form and coloration. This species is also known for its disease resistance (particularly fire blight resistance.) However, Callery pear tree is an invasive species, so much so that nurseries will no longer be allowed to sell the plant in Pennsylvania in 2024.

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Callery Pear Tree Appearance

Callery pear has a distinctive appearance with crucial aspects that can help homeowners and plant health care experts quickly identify the plant.

  • Size: Callery Pear trees typically grow to around 16 to 26 ft tall, or approximately 5 to 8 meters, often with a conical to rounded crown.
  • Leaves: The leaves are oval-shaped and about 1-1⁄2 to 3 inches long, with a dark green color in early spring before the leaves turn yellow, orange, or red in the fall.
  • Flowers: The flowers are white and grow in clusters, have about five petals, and are about 3⁄4 to 1 inch in diameter.
  • Fruits: The fruits of the Callery pear are small, less than 3⁄8 of an inch in diameter. In addition, the fruits have a rugged, almost woody feel but are softened by frost, after which birds readily consume them.

Damage Caused by Callery Pear

Callery pear branch with fruit- callery pear invasive species - Burkholder Plant Health Care

Callery pear trees are invasive plants in many parts of the country and have damaged the landscapes and gardens of Pennsylvania homeowners. One of the significant reasons Callery pears cause so much damage is how the trees grow. These trees form dense thickets which displace native plants and animals. The dense thickets push out native trees or other plants that may compete with the Callery pear for water, soil, and space.

In addition, some cultivars (a type of cultivated plant that people have selected for desired traits), such as the ‘Bradford pear,’ are susceptible to storm damage, becoming disfigured or killed by strong winds and winter weather. So there is also a risk of the branches falling during strong winds and storms and damaging other things around the tree, like property or people.

What Makes Callery Pear an Invasive Plant

Like other species of plants we have discussed in this series, Callery pear has many qualities that enable the tree to spread quickly. One primary reason is the fruits discussed previously. The tree species produce large quantities of fruits that birds consume, and then those birds fly and relocate to new areas, passing the seeds in droppings into the soil, allowing new Callery pear trees to grow.

What makes Callery pear unique among the other invasive plant species we have talked about is the role of cultivars in spreading its population. Cultivars were initially bred to produce sterile fruit. However, different varieties can cross-pollinate, which results in viable seeds. When these cultivars grow close enough to each other to cross-pollinate, the trees produce fertile seeds that can sprout once dispersed.

Treating & Controlling Callery Pear

Callery pear can be challenging to control, but some methods exist for managing or removing the population from a landscape.

  • Small plants and their roots can be removed by hand, but larger trees require more extensive removal with specialized equipment, and herbicide application must be used as a follow-up.
  • Foliar herbicide applications can be done from around mid-May to early-mid October. These foliar treatments are ideal for landscapes with a low to moderate density of trees, which are less than 10 feet tall.
  • Basal bark treatments can be applied to the stems of a Callery pear tree throughout the year, with some exceptions (particularly during snow or rainy weather.)

As always, these control and treatment options require specialized, extensive knowledge of plant health care techniques. So call a plant health care expert if you need help with Callery pear in your landscape.

Contact Burkholder PHC for Expert Treatment of Plant Health Care Issues

The Callery pear tree invasive plant can overtake landscapes, and its dense thickets prevent native plant species from growing. To keep your landscape and native species healthy and able to thrive, we recommend a professional evaluation to help remove the plant and control any adverse effects. Our evaluation is free, and the proper treatments can help improve the health of your landscape. Contact Burkholder PHC today for a free consultation.

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What Is Plant Health Care (PHC)?

Plants can add a great deal of value and beauty to a landscape if they are healthy. While plants have the same basic needs, one plant’s health risks may differ entirely from another, even those on the same property. So, what is Plant Health Care? Plant health care is the answer to the complexities and intricacies of keeping various kinds of plant life in the same landscape healthy. By carefully considering each plant’s needs and supplying preventive care, high-value plants can remain healthy and make your landscape vibrant and attractive.

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What Is Plant Health Care, And What Is The Goal?

Plant health care is a comprehensive, proactive, and holistic approach to maintaining the health and vitality of all plants on a person’s property. Plants reside close to each other in a landscape, so actions that affect one plant (such as a tree) could affect others (such as a nearby shrub or flower bed). Plant health care specialists use this type of plan as the basis of their services, carefully considering the complexity of the plant life and creating a holistic program that ensures all plants will grow and thrive.

The primary goal of a plant health care program is to foster and maintain the proper environment for all plants on a property, from trees and shrubs to flowers and grasses. Preventive treatment is another core goal, as preventing health issues from occurring is more effective than resolving ones that appear or spring up. Plants are susceptible to many environmental conditions, such as weather, pests, and diseases. Fixing these issues is essential, but plant health care takes an extra step and proactively creates the environment and conditions that prevent problems from occurring in the first place. Below is a before and after comparison of a crape myrtle we treated for aphids. You can see that our efforts brought the plant back to full health.

  • Crape Myrtle Aphid after Treatment - Burkholder PHC

    Crape Myrtle Aphid Before Treatment

    Crape Myrtle Aphid after Treatment

  • Crape Myrtle Aphid after Treatment - Burkholder PHC

    Crape Myrtle Aphid After Treatment

What Is Involved in Plant Health Care?

Plant health care involves various tasks to maintain and promote the health of all plants on a property. Here are a few examples of plant health care tasks:

Soil testing: Testing the soil helps identify any nutrient deficiencies or imbalances and determines the soil’s pH level. This information helps define the appropriate fertilizers and soil amendments needed to support plant growth.

Pest and disease control: Regularly monitoring and identifying pests and diseases can help prevent their spread. Different treatment options, such as organic and chemical treatments, can be used to control pests and diseases.

Pruning and trimming: Proper pruning and trimming techniques can help maintain the health and shape of trees and shrubs, promote new growth, and remove dead or diseased branches.

Water management: Proper watering techniques can help prevent under or over-watering that can stress plants and make them susceptible to disease.

By incorporating these services and more, a plant health care expert can develop a comprehensive program to ensure all plants on a property remain healthy and vibrant.

  • Juniper shrub before corrective pruning - what is plant health care - Burkholder PHC

    Juniper Shrub Before Treatment

  • Juniper shrub after corrective pruning - corrective pruning and structural pruning - Burkholder PHC

    Juniper Shrub After Treatment

What Are The Benefits of Plant Health Care?

One of the benefits of plant health care is that your landscape stays beautiful. Plants need to be healthy to maintain their beauty, and they require a comprehensive plan that supports and promotes growth. The holistic and proactive approach also means that professionals can resolve any issues that affect your plants’ health and beauty much sooner, before any long-term damage.

In addition to a more attractive landscape, a plan that ensures your plants are healthy can help make your property more valuable. For example, large, mature trees can add significant value to a property, but the trees need to be healthy and safe to provide that value. A holistic, thorough care plan can keep trees beautiful and healthy throughout their entire life cycles, so your trees can continue to be a good investment, both financially and aesthetically.

Contact Burkholder PHC to Keep Your Plants Healthy and Beautiful

Now that you know what plant health care is, are you ready to plan for your landscape and ensure your plants stay healthy and vibrant? Contact Burkholder PHC for a consultation. We offer various services, such as plant growth regulators, pest control, deer deterrents, and soil care. Our specialists have wide experience maintaining landscapes in the Main Line area. To learn more about our services, request a free consultation today.

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Tree Root Health and Root Zone Invigoration

Trees are an essential part of any landscape, providing shade and other benefits that make them an attractive option for homeowners. However, tree roots need to be healthy and strong for the tree to survive. Root zone invigoration (RZI) is a process that helps ensure the health of trees.

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Root Zone Invigoration Process

Root zone invigoration (RZI) is a process that helps ensure the health of trees. RZI will improve tree growth and help prevent disease and insect problems. The process can also reduce irrigation requirements by increasing water absorption deep in the soil profile. The process can benefit drought-stricken areas or regions where water use restrictions are in place.

Why Trees Need RZI

Plants need healthy, biologically active, well-drained, and well-aerated soil to thrive. Unfortunately, most landscape plants are growing in compacted or otherwise unhealthy soil, with little or no pore space for oxygen and water penetration. A tree’s roots absorb water and nutrients so when a tree’s root system is compromised by poor soil conditions, or events like construction work, root zone invigoration is a good solution.

Root Depth

If a tree’s roots lack depth or strength, the tree may be unable to withstand adverse weather conditions. A shallow root system could mean that a tree will lack the proper stability to remain upright during high winds, for example.

Root Health

A healthy root system is essential for good health overall. Roots are responsible for absorbing water and nutrients from the soil, so a tree will struggle to survive if the roots are damaged, compacted, or broken off. Damage can occur when construction work occurs in areas where trees grow, such as during road construction near forested areas.

Minerals & Nutrients

Young trees absorb nutrients from the soil through their roots. As a result, if the soil lacks a particular mineral or nutrient, the tree can have difficulty growing correctly and developing into a healthy adult tree.

Preventing Health Issues

Without enough carbon dioxide (CO2), trees are unable to produce the sugars needed for energy and growth. If CO2 levels are too low, leaves will become pale green or yellowish-green instead of dark green and chlorophyll-rich. In addition, the tips of branches may turn brown due to a lack of photosynthesis. Eventually, these branches can die off altogether, leaving bare trunks without leaves.

How Root Zone Invigoration Works

Burkholder PHC root zone invigoration makes use of an air spade. This spade directs compressed air to break apart heavy, compacted soil, without damaging the root system of the plants. Performing root zone invigoration effectively and safely requires knowledge of arboriculture and experience, so hiring a certified arborist is recommended if your trees need root zone invigoration.

Benefits of Root Zone Invigoration

Root zone invigoration helps to decompact thick clay soil and adds pore space for adequate water and air. Root-zone invigoration can be utilized on established trees as well as in preparation for new plantings, and gives the opportunity to amend the soil with nutrients, rich compost, and soil conditioners.

Our plant health care experts may treat trees with RZI after disturbances like erosion, soil removal, or construction work so the trees can continue to uptake needed water and nutrients.

Contact Burkholder PHC for Root Zone Invigoration

For preferred and high-value plants or those that are beginning to show signs of decline, root-zone invigoration is the most beneficial service that you can give them. If you believe that your trees need root zone invigoration, send us an email or give us a call. Burkholder PHC has a team of experienced, qualified arborists who will visit your property, conduct a plant health care evaluation, diagnose the problems, and inform you of the recommended treatment options. In addition, we provide a proactive approach to maintain your trees’ health and appearance. Contact us today for a free consultation.

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The Ideal Time for Corrective Pruning

Corrective pruning is a crucial aspect of plant care, and the timing of this activity can significantly impact the health and growth of plants and trees. Choosing the ideal time for corrective pruning ensures trees can recover and heal properly, reducing disease risk and promoting healthy regrowth. Pruning at the incorrect time, on the other hand, can lead to increased vulnerability to pests, diseases, and environmental stress, ultimately hindering the tree’s overall health and appearance.

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The best times for pruning can vary depending on the season and the tree species.

  • Late winter/early spring (January to March) is an ideal time for corrective pruning for most plant species. This time is the dormant season for most plants, so energy is not being spent on growing. As a result, pruning a mature tree during late winter means that the tree is more likely to heal after pruning because there is no sharing of nutrients between healing and growing new branches or leaves.
  • Late spring/summer is generally not the best time for corrective tree or shrub pruning for most types of trees. Trees and shrubs are actively growing during this time, so spring and summer pruning can stunt growth, lead to diseased branches, and slow wound healing. Having pruning done in the winter creates the ideal conditions for spring growth.

Regarding specific tree species:

Evergreen trees: Corrective pruning can be done at any time of year except for autumn because pruning during autumn can stimulate new growth that may not have time to harden off before winter, making the tree vulnerable to frost damage. The best time to prune evergreen trees is in late winter or early spring to avoid sap loss as sap flow is generally lower during the dormant season.

Fruit trees: Most fruit trees should be pruned in late winter or early spring, just before the buds swell. Pruning during this period can help promote healthy growth and fruit production for the upcoming season. Pruning just before bud swell is ideal, because identification of dormant buds is easier and this allows for proper shaping and thinning. On the other hand, some fruit trees, such as peaches and nectarines, are best pruned in late summer or early fall. Pruning during this period can help reduce the risk of diseases such as peach leaf curl, which is best managed by pruning during the late summer or early fall when the trees are dormant but after the risk of infection has passed.

Flowering shrubs: Most flowering shrubs should be pruned after blooming. Pruning after flowering allows you to enjoy the blooms and also protects next year’s flower buds, which often form soon after the current year’s flowers fade. Some shrubs, such as hydrangeas, are best pruned in late winter or early spring depending on their specific type and blooming habit.

An essential aspect of plant health care is considering the specific needs of different plant species when determining the ideal time for pruning. By understanding various plants’ seasonal requirements and growth patterns, certified arborists can ensure that corrective pruning efforts are effective and supportive of optimal plant health.

The Consequences of Neglecting Tree Pruning

Neglecting the need for corrective pruning can have dire consequences for long-term tree health and aesthetic appeal. Trees can suffer from reduced aesthetics and structural integrity without regular pruning, causing unbalanced growth and potential aesthetic damage. Neglected trees are prone to deadwood accumulation, suckers, and water sprouts, which detracts from the overall appearance and can also lead to increased susceptibility to disease and pests.

Furthermore, overcrowded branches can lead to wounds and damage, leading to a weak branch structure and potential safety hazards. Weak or dead branches are also more prone to breaking, which can lead to falling branches that risk property and personal safety.

In addition, neglecting pruning can result in stunted growth and a weak root system, ultimately reducing the tree’s lifespan. By ignoring the need for corrective pruning, homeowners are essentially sentencing their trees to a future of compromised health and vitality. Regular pruning helps ensure the longevity and well-being of your trees.

Professional Corrective Pruning

Juniper shrub after corrective pruning - corrective pruning and structural pruning - Burkholder PHC

When pruning trees, hiring a professional, certified arborist has distinct advantages over attempting the task yourself. Corrective pruning requires specific knowledge of pruning techniques and cuts, tools, and methods that preserve the health of a tree.

Professional tree care experts have the knowledge and experience to assess the needs of each tree correctly and use proper pruning techniques. This results in healthier, more vibrant trees that require less maintenance over time, ultimately saving you money.

Moreover, professional tree pruning can prevent costly damage caused by improper techniques and prolong your trees’ life. Professionals can also identify and correct any existing issues while pruning, helping to ensure your trees’ long-term health and vitality.

Investing in professional tree care services saves you time and money in the long term and ensures that your trees receive the best care possible. You can enjoy healthy, well-maintained trees for years with professionals’ expertise and attention to detail.

Get Expert Corrective Pruning from Burkholder PHC

Are you struggling to keep your plants healthy and thriving? Burkholder PHC’s certified arborists and plant health care experts are here to help you, whether you need advice on the ideal time for corrective pruning for your trees and shrubs, tree care, or plant care and maintenance. With years of hands-on experience, we can provide you with the guidance and support you need to ensure the health and longevity of your plants. We offer a free consultation to get you started on the right path. Take the next step towards healthier, more beautiful greenery by booking a consultation with us today.

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Japanese Barberry Invasive Plant

Japanese barberry (Berberis thunbergii) is a popular ornamental plant used in landscapes across the east coast of the United States. Native to Japan, the plant was introduced into the United States in 1875 and has since become one of the most highly invasive plants in temperate regions worldwide. The Japanese barberry invasive plant’s ability to grow under various conditions makes controlling the effects difficult.

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What the Japanese Barberry Invasive Plant Looks Like

Size: The shrub is compact and dense, rarely exceeding 4 feet in height. The brown, spiny branches will also touch the ground.

Flowers: The flowers are pale yellow and often have around six petals each.

Fruit: Berries are glossy bright red to orange-red. Each berry is also around 1/4 to just under 1/2 inch long.

Leaves: Japanese barberry leaves are distinctly spoon or spatula-shaped with smooth edges. The leaves typically have a thick, leathery, and bright green appearance but can have some red or purple coloring and are 1 inch or less long.

Stem: The exterior of the stem is grooved and rusty brown with single spines, while the inner bark is bright yellow.

Damage Caused by Japanese Barberry

One of the reasons the Japanese barberry invasive plant causes damage is that the shrub is a host for several human diseases, including Lyme disease. Bites from the black-legged or deer tick (Ixodes scapularis) transmit the disease, making Lyme disease a common vector-borne illness in the United States. In humans, early symptoms of this disease include rash, fever, headaches, and tiredness. If untreated, symptoms may also include joint pains, severe headaches, or heart palpitations.

The microclimate of Japanese barberry is favored by ticks, because it protects them from temperature and humidity fluctuations as opposed to relatively taller and thinner native vegetation. In addition, the relatively low stature of barberry plants provides plenty of opportunities for ticks to come in contact with humans.

japanese barberry invasive plant- Burkholder PHC
tick on a leaf- japanese barberry invasive plant- Burkholder PHC

Why Japanese Barberry is Highly Invasive

One of the reasons Japanese barberry has been highly invasive is due to a high tolerance for shade. The plant can tolerate high or low amounts of sunlight and even dry conditions. This has made Japanese barberry particularly troublesome in urban or suburban areas where large trees provide valuable shade and create environments where the invasive plant thrives. In addition, the plant has few natural predators, as deer prefer to feed on other plants. The result is that the plant is able to spread quickly and thrive in various environments.

Pennsylvania Bans Japanese Barberry

The Japanese barberry invasive plant has caused so much harm to landscapes and people that the Pennsylvania Department of Agriculture designated the plant as a noxious weed. As a result, Japanese barberry cannot be legally sold or cultivated in the state. The ban was implemented in October 2021 and penalties are rolling out to nurseries or other landscaping businesses that sell the plant. As a result, property owners should not buy Japanese barberry for their landscapes and should contact a plant health care expert to have the invasive plant removed from their property if necessary.

Controlling & Removing Japanese Barberry

If you have Japanese barberry on your property, you can work with plant health care professionals to remove it. Be aware that the seed of this species also remains viable in the soil for up to 10 years. As a

result, removal must be followed by at least two or three years of follow-up monitoring and control. In addition, seeds germinate in early spring and grow quickly. The seeds can be challenging to remove via mechanical means because the seeds often grow in dense stands in which individual plants are inaccessible.

Sprouting from stolons (horizontal shoots) or roots is another problem that may occur after removal efforts have been completed. Work with a professional to carefully monitor and control these sprouts.

Contact Burkholder PHC for Invasive Plant Treatment & Removal

The Japanese barberry invasive plant poses risks to human health. As a result, we recommend a professional evaluation to help remove the plant and control any adverse effects. Our evaluation is free, and proper treatments can restore your landscape’s health. Contact Burkholder PHC today for a free consultation.

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Burkholder PHC Contributes to New Plant Health Care Discoveries and Achievements

Starker Wright, Plant Health Care Manager | Burkholder Plant Health Care

Malvern, Pennsylvania – January 27, 2024– Burkholder PHC has recently been recognized for several notable Plant Health Care discoveries and occurrences. Starker Wright, manager of Burkholder PHC, has been directly involved in the following:

  • Rose rosette in bright pink roses - Burkholder PHC

    Rescue treatment for eriophyid/rust mite damage

    Privet, rose, pear, spruce, and hemlock commonly show bronzing of foliage that has been attributed to tip/twig blights and foliar diseases, but fungicide treatments have not been effective in halting disease progression. In 2023, Burkholder PHC identified eriophyid/rust mites on affected plants (particularly privet and spruce), and treatment effects have been spectacular.

  • Formal identification (with Penn State Insect Identification Lab) of Philoeosinus canadensis

    Philoeosinus canadensis is a tiny borer beetle that has killed stressed ‘Green Giant’ arborvitae trees in the Main Line area for several years. This is the first identification of this beetle in Pennsylvania, more commonly found along the U.S.-Canadian border from Maine to Michigan. With identification, Burkholder PHC developed a management plan for high-risk arborvitae trees before the damage becomes irreversible.

  • Roses with full season management by Burkholder PHC - plant health care discoveries

    Full-season management plan for roses

    Roses can be a spectacular landscape plant but are among Main Line’s most pest-damage-prone plant groups and commonly become an eyesore by late spring. Slug sawflies, Japanese beetles, deer, rabbits, spider mites, rust mites, thrips, aphids, scale insects, and a wide range of plant diseases severely damage roses yearly. However, with attentive and specific management tactics, roses can be kept clean for the growing season, ensuring continuous blooming through fall.

  • Hybrid maple tree with leopard moth damage - Burkholder Plant Health Care discoveries

    Formal identification (with Penn State Insect Identification Lab) of Zeuzera pyrina

    Burkholder PHC identified the Zeuzera pyrina (leopard moth) infesting and eventually killing landscape hybrid maples.

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About Starker Wright

Mr. Wright has extensive knowledge and practice in the field of plant health care, beginning with a degree from the University of Massachusetts in agroecology. Mr. Wright’s experience includes

  • serving for 8 years as the field coordinator of the University of Massachusetts Tree Fruit Integrated Pest Management (IPM) Program
  • developing and testing biologically based management techniques for key native and invasive pests of tree fruit with the Insect Behavior and Ecology Program at the Appalachian Fruit Research Station with USDA-Agricultural Research Service in West Virginia
  • authoring and co-authoring over 80 research and extension publications, focusing on integration of biological, cultural, and chemical management of tree health
  • working with Bartlett Tree Experts in Dublin, Pennsylvania as a Plant Health Care Specialist, Arborist Representative, and Local Office Manager
  • working as Plant Health Care manager for Burkholder PHC in Malvern, PA

Starker Wright, Plant Health Care Manager | Burkholder Plant Health Care

See Burkholder Plant Health Care 2022 Discoveries and Achievements

  • Federal quarantine identification of white rust on chrysanthemum, confirmed by USDA-APHIS.
  • First active sampling program in Pennsylvania for vascular streak dieback disease in redbud.
  • First identification of crape myrtle bark scale in Pennsylvania, confirmed by Penn State Insect ID Lab.
  • First identification of camphor shot borer damage in hemlocks, confirmed by Penn State Insect ID Lab.
  • Submission of field research article “Pre-Emergent Control of Spotted Lanternfly” in collaboration with Bartlett Tree Experts.
  • Continuing research with Bartlett Tree Experts and University of Maryland on potential impact of native predators on spotted lanternfly eggs.

About Burkholder Plant Health Care

Burkholder Plant Health Care is a sister company to Burkholder Landscape, a local company that has been a full-service landscape designer caring for plants and landscapes since 1996. The company has a staff of plant specialists that is educated, trained, experienced, and certified to manage all insect and disease pests, soil chemistry, and plant physiological problems to deliver genuine, lasting results. Burkholder PHC’s program emphasizes proper diagnosis and precise treatment, along with state-of-the-art, research-backed methods and equipment. The team strives to maintain a close relationship of open and reliable communication with all clients, building partnerships that will promote the development of beautiful, long-lasting, healthy landscapes. For more information about recent plant health care discoveries or the company, visit their website at or call 610-426-1662.

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Burkholder Plant Health Care Year in Review

As homeowners, we know that you are invested in your landscape, both financially and emotionally. Motivation for this investment may be strictly practical (contribution to property value), aesthetic (appreciation of the beauty of plants), ecological (contribution to the biome), or competitive (well, neighbors). Motivation to enhance and care for landscapes is more likely from combining these factors and many others. Without regard to underlying motivation, the fact is that an established and cared-for landscape returns on the investment.

The most advanced, durable, and overlooked component of landscape plant maintenance is biological care, which involves the following:

  • Maintaining soil nutrition
  • Controlling insect and disease pests
  • Managing plant structure and physiology

In today’s environment, biological care is critical in preserving longevity, vigor, and beauty in landscape plants, combatting invasive and explosive pests, compensating for the depletion of soil nutrients, and correcting losses in plant resiliency.

Why Burkholder Plant Health Care?

At Burkholder Plant Health Care, we aim to provide the highest biological and structural care level for homeowners in our region. We are staffed with experienced, certified professional technical specialists and equipped with state-of-the-art equipment, management strategies, and treatment materials to achieve this. In our program, a critical element of the effective protection of landscape plants is keeping abreast of dynamic growing conditions in terms of seasonal weather patterns that contribute to plant stress and a constantly changing complex of insect and disease pests.

Below is the Burkholder Plant Health Care Year in Review, where you can learn about the top issues we saw and treated for this year in Main Line landscapes. 

Climatic Conditions

This season, three climatic events had a significant impact on landscape plant health:

  • Dec 22-Dec 24, 2022

    Conditions: Three days of high winds and plummeting temperature, with winds sustained at 30 mph and daily low temperatures into single digits.

    Effects: Severe winter burn (desiccation) on evergreen, deciduous plants, especially laurel, holly, and boxwood.

  • May 2-June 12, 2023

    Conditions: Prolonged lack of rainfall during a critical growing period, with less than ¼” of rainfall recorded in 6 weeks.

    Effects: Widespread planting/transplant failures in non-irrigated landscapes. Stunted growth/reduced flowering in many established landscape plants.

  • Sept 9-Sept 29, 2023

    Conditions: Twelve days with recorded rainfall in a 3-week span, totaling 6″ of rainfall.

    Effects: Late-season onset of root diseases, particularly phytophthora root rot in boxwood, laurel, and rhododendron.

Notable Plant Health Care Issues in 2023

  • white prunicola scale was one of the noted issues in the Burkholder Plant Health Care year in review

    White Prunicola Scale

  • square image of boxwood leafminer damage | plant health care year in review | Burkholder PHC


  • Phytophthora Root Rot is an issue in Burkholder Plant Health Care Year in Review

    Root Rot

  • Rose rosette in bright pink roses - Burkholder PHC

    Rust Mite/
    Eriophyid Mite

  • Invasive

  • Deer Browse and
    Antler Rubbing

  • Rake in Soil | Plant Health Care by Burkholder Landscape


White Prunicola Scale

White Prunicola Scale in a tree - Burkholder Plant Health Care Year in Review

This pest can cause severe damage to cherry laurel, skip laurel, and flowering cherry/plum. White prunicola scale also infests privet, lilac, boxwood, and holly. This area has three generations of this pest per year, with the third being particularly explosive in September. The insect creates a white, fuzzy coating on plant stems and can cause significant yellowing and branch death when populations are high.

Boxwood Complex: Leafminer, Psyllid, Spider Mite,  Volutella Blight

boxwood leafminer damage | plant health care year in review | Burkholder PHC

Boxwood leafminer, a type of fly larva, has become the most common destructive pest for boxwoods. These larvae feed on the leaves, causing them to brown and eventually fall off. This year, psyllids and spider mites were also active, leading to a decline in the quality and appearance of boxwoods across the region.

Additionally, boxwoods are susceptible to several diseases, with volutella blight being the most common. This disease is particularly harmful to plants weakened due to pests or environmental factors.

Learn More About Boxwood Issues

Phytophthora Root Rot/Root Diseases

rhododendron leaves with phytophthora root rot | Burkholder Plant Health Care Year In Review Issues

Soil diseases, especially phytophthora, can remain inactive for many years but cause significant damage when soil moisture is high. These diseases have many hosts, affecting plants like the following:

  • Boxwood
  • Laurel
  • Azalea
  • Rhododendron (seen in image above)
  • Pieris
  • Holly
  • Dogwood

The infection destroys fine roots and progresses through the underground water transport system, causing above-ground symptoms that resemble drought stress. A second soil/root disease has emerged in the last few years, with particularly severe damage in holly, especially Japanese holly. Although symptoms of these two diseases are similar and the diseases thrive in similar conditions, management recommendations are completely different, so thorough identification is required for effective management.

Learn More About Phytopthora Root Rot

Rust Mite/Eriophyid Mite

Rose rosette in bright pink roses - Burkholder PHC

Eriophyid/rust mites are causing significant damage to plants such as privet, cypress, hemlock, and spruce. These tiny mites make detection difficult, leading to damage before homeowners notice their presence. Another species of eriophyid mite is responsible for spreading the rose rosette virus, which causes extensive damage to roses.

Due to the challenge in detecting these pests, eriophyid rust mites have caused damage to plants for many years. However, effective tools are now available to control these mites on privet and conifers. As a result, we have observed a remarkable recovery of previously mite-damaged plants.

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Invasive Weeds

Rake in Soil | Burkholder Plant Health Care year in review

The following species of weeds are invasive to Pennsylvania and can harm homeowner’s landscapes.

  • Canada Thistle (shown above)
  • Bindweed
  • False Buttercup/Celandine
  • Yellow Nutsedge

Deer  Browse and Antler Rubbing

diagram of trunk with deer rub damage and deterrents | plant health care year in review | Burkholder PHC

In this area, deer are likely the greatest hurdle to establishing new landscape plants, maintaining attractive architecture on mature plants, and ensuring full flowering in ornamental plants that are also feeding targets for deer.

Many landscape plant species are attacked by deer, but the worst are:

  • Hosta
  • Evergreen Azalea
  • Rhododendron (especially PJM)
  • Wintercreeper
  • Rose
  • Hydrangea
  • Flowering Cherry/Plum/Apple
  • Tulip

Even with clear preferences for some plants, feeding damage from deer extends deep into the list of local landscape plant species. To combat this problem, we have developed our deer repellent blend, combining effects of feeding repellents, predator signals, and behavioral deterrents. We began using this repellent in 2022, which has proven effective, with good to excellent results throughout the spring/summer and fall/winter seasons. We strictly adhere to a re-treatment interval of 60 days or less.

Learn More About Deer Deterrents

Soil Conditions/Soil Nutrition

Rake in Soil | Burkholder Plant Health Care year in review

Two critical factors for healthy landscape plants are soil moisture and nutrition. Optimal soil moisture and nutrient levels ensure healthy, resilient plants. Burkholder Plant Health Care samples soil on participating properties and applies prescription soil amendments each season for healthy plant growth.

Soil Moisture

Maintaining ideal soil moisture levels to ensure your landscape plants thrive is vital. Generally, ideal soil moisture levels range between 20% and 60% but vary depending on the soil type and the specific plant species. The middle ground of 40% is a good target to aim for.

Soil moisture levels that are consistently lower than 20% or greater than 60% can be equally damaging to root systems, so it’s essential to calibrate your landscape watering routine accordingly. We will begin monitoring soil moisture levels during each field visit to client properties to simplify watering recommendations.

Soil Nutrition

Soil nutrition is a crucial consideration for the health of the plants in your landscape. With sufficient nutrients like nitrogen, phosphorus, potassium, and micronutrients, as well as a solid foundation of proper pH levels and soil structure, your plants can reach their full potential regarding maturity, health, and strength. Poor soil conditions can also make your plants more vulnerable to pest problems and
damage from environmental stress.

All properties should have soil analyzed, and many will need to focus on managing and correcting soil nutrient levels. This can make the difference between having healthy plants that require little maintenance and constantly dealing with plant health issues. At Burkholder Plant Health Care, we take soil chemistry seriously. We sample the soil on participating properties every three years and apply prescription soil amendments in each growing season’s spring (March) and fall (October).

Learn About Soil Management

Burkholder PHC Accomplishments in 2023

Our Burkholder Plant Health Care Year in Review would be incomplete without mentioning a few achievements of our team.  These include:

  • Formal identification (with Penn State Insect Identification Lab) of Philoeosinus canadensis
  • Full-season management plan for roses
  • Rescue treatment for eriophyid mite damage
  • Formal identification (with Penn State Insect Identification Lab) of Zeuzera pyrina

Learn more about these accomplishments in our new article.

Look Back at the Burkholder PHC 2022 Year In Review

Contact Burkholder PHC for Exceptional Treatment of Plant Care Issues

If you are a current or past client of Burkholder Plant Health Care, thank you for trusting us with the care of the structure and biology of your landscape plants. If you have not brought our services onto your property and are interested in an assessment of the condition of your landscape plants, just let me know ( All of our initial evaluations, sampling, and diagnostics are free for current or past clients of Burkholder Brothers. For more information about the Burkholder Plant Health Care Year in Review, give us a call.

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Examples of Deer Damage to Trees

Deer are a common sight in Pennsylvania, and residents enjoy seeing deer. However, their presence can be a problem for homeowners, as deer cause damage to gardens and trees. Deer create different types of damage depending on their behavior in a residential area. This article will give you examples of deer damage to trees with photos to help you identify the problems.

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Antler Rub

One example of deer damage to trees is antler-rub. A deer rubs their antlers on a tree because the rubbing is a form of communication. Antler-rub is a way for deer to mark territory and attract mates and is done during winter. The antlers are covered with a velvet-like substance (a soft tissue that grows from the bone) during this time, and rubbing removes the velvet to make way for a new cover in spring. In addition, bucks use their antlers to push apart tree branches as they walk through them and rub against trees to create scratch marks, called “horizontal forehead marks.” If a buck has no other way to communicate his presence in an area, he will make these marks on trees using his antlers as tools.

Below are images of what antler-rub looks like:

  • deer-antler-rub-unprotected-burkholderphc

  • Unprotected tree with antler rub deer damage to trees - Burkholder PHC


In these images, the tree bark has been scratched away due to antler-rub, leaving the stem exposed. Specifically, the cambium, the layer that resides between the inner and outer bark, is exposed after antler-rub. Cambium helps nutrients move throughout trees. So, when the layer is exposed, weather, pests, and diseases can harm the tree.

To mitigate antler-rub, we can apply a stem guard on trees. Stem guards are metal or plastic sleeves or wraps that encircle tree trunks to keep them safe from antler-rub without restricting the tree in other ways. If a deer rubs their antlers on a tree with a guard, the guard blocks the antlers from making contact with the bark, preserving the tree’s health and inner layers, as seen in the images below.

  • Tree protected from deer damage to trees - Burkholder PHC


  • Tree protected from deer damage to trees - Burkholder PHC



Deer have a diverse diet and are herbivores, which means that deer damage to trees can be extensive and affect other plants in your yard. Some deer eat plants, including leaves, twigs, the bark of trees, flowers, fruits, and seeds. Their feeding habits vary depending on what is available at the time, but the damage caused is generally consistent. As deer eat plants in residential neighborhoods, they tear grass and are constantly stomping and compacting soil, looking for food. This is “browsing,” and you can see the aftermath of this behavior in the images below.

  • Deer browsing damage - deer damage to trees - Burkholder PHC


  • Deer browsing damage - deer damage to trees - Burkholder PHC


Contact Burkholder for Deer Repellent Services

If you want to prevent deer damage to trees on your property, contact Burkholder PHC. Our team has experience helping homeowners protect their yards from deer and other pests and diseases. In addition, our plant health care team is highly knowledgeable about all aspects of plant health care issues and solutions. We will work with you, inspecting your property to determine the ideal solutions to keep your plants healthy and beautiful. Contact us today to see how we can help you.

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Essential Winter Plant Health Care Services

During the winter, while the tree leaves have fallen and the colors of your backyard may seem to have faded away, a complex world of plant life awaits spring’s arrival. Ensuring robust plant health throughout these months requires specialized care. Winter plant health care services are essential for keeping your plants vibrant and healthy for spring.

Learn About Seasonal Plant Issues

Soil Amendment: Nourish Your Plants for Year-Round Vitality

Horticulture is characterized by fluctuating seasons and plant metabolisms, where quality soil is a constant vitality force. In winter, a well-nourished soil bed with a prudent blend of nutrients, such as nitrogen and potassium, guarantees healthier, more robust plants equipped to endure winter climates.

As part of our soil amendment services, we use soil test kits to analyze nutrient composition. Once the testing is complete, our team reviews the results to ascertain the type and number of amendments necessary for each landscape.

Regarding the specific amendments, our team uses specific fertilizers during the fall and winter to provide the necessary nutrients for healthy plant growth. These fertilizers ensure that essential macro and micronutrients are available for absorption and storage, vital for the initial spring growth period.

Doing so will promote healthy growth, protect against insect and disease infestations, and help your plants and trees endure harsh environmental conditions throughout the year.

Deer Repellents: Safeguarding Your Plants from Winter Hazards

During fall and winter, the prospect of damage to your plant life from deer feeding and antler rubs heightens because food becomes scarcer in their natural environments. Such activities severely threaten the health and growth of your plants. However, some methods can prevent such damage through the judicious use of deer repellents, effectively mitigating or eliminating the risks posed by deer activity. These methods are selectively used depending on the deer-related problems your landscape is facing:

  • Antler-Rub Damage: Metal or plastic trunk sleeves can protect newly planted trees from antler rubbing in winter. Odor deterrents can also deter deer from unprotected trees.
  • Feeding or Browse Damage: We use area and contact repellents to protect plants from deer feeding on them during dormancy. Area repellents create a boundary around a property or bed to prevent deer from entering. Contact repellents change the taste and texture of the plant, making them less desirable to deer. Over time, this helps deer learn to avoid protected plants.

damage from deer rubbing on tree trunk - winter tree care services - Burkholder PHC

Pruning: Shaping Strong Foundations for Spring Growth

Pruned apple tree- winter plant health care services - BurkholderPHC

The period between December and February presents a suitable time for homeowners and arborists to undertake the crucial dormant and structural pruning process. This process is a carefully orchestrated measure to optimize trees’ and shrubs’ health, appearance, and longevity.

  • Dormant pruning entails the removal of dead, diseased, or damaged branches while the tree or shrub is dormant, both to prevent the spread of pests and diseases and reduce stress on the plant.
  • Structural pruning focuses on making specific pruning cuts to shape the plant for proper growth and development. This includes eliminating crossing or rubbing branches, which can create wounds and provide entry points for pests and diseases.

By performing these specific winter plant health care services, arborists can redirect the plant’s energy to the most vigorous branches, thus encouraging healthy growth. In addition, dormant and structural pruning enhances light and air penetration, which is critical for the plant’s overall health and vitality. Pruning also offers an opportunity to eliminate unwanted growth or deadwood, which can detract from the plant’s aesthetic appeal.

Tree and Shrub Removal: Making Informed Decisions

Removing trees and shrubs is a complex process that requires careful planning and execution, particularly during winter, when weather conditions can be challenging. However, removing trees and shrubs becomes necessary in certain situations, such as disease infestations or safety threats.

The removal process begins with thoroughly inspecting the site to determine which trees or shrubs need to be cut down and removed and how large each is. We then use various tools to remove the tree or shrub, including chainsaws, telescoping poles, and buckets. Once the trees or shrubs have been removed, we use specialized equipment like stump grinders to smooth out the area.

An important note is to seek professional advice before any DIY work. Removing shrubs and trees is complex and challenging, especially if trees are close to other structures like houses or power lines. Our team of professionals is available to provide guidance and advice on tree and shrub removal so you can make an informed decision that is right for you.

Winter Tree Treatment: Protecting Against Winter Stress

During the winter season, trees are prone to experiencing water loss, commonly called tree desiccation. This phenomenon occurs when the rate of water loss exceeds the tree’s capacity to absorb water, ultimately leading to tree damage or death. To prevent this, we provide anti-desiccant and anti-transpirant treatments that act as protective barriers against water loss. We meticulously administer these treatments to mitigate winter stress, promote enduring plant health, and reduce the risk of tree damage or death.

Contact Burkholder PHC for Winter Plant Health Care Services

Burkholder PHC offers comprehensive winter plant health care services to maintain the natural rhythm of your garden’s life cycle. Our experts are committed to sustaining the health and vibrancy of your green spaces. We invite you to entrust the care of your garden to us to ensure its vitality and longevity. Contact Burkholder PHC to discuss how we can provide our expertise and services to help you maintain the health of your garden throughout the winter season.

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