Misconceptions about winter tree care can lead to “passive damage”—harm that isn’t immediately visible until the following spring or summer. That’s especially true if you live in New England.
Below are seven common mid-winter tree care tips that can physically and biologically hurt trees:
1. Watering prevents mid-winter desiccation
When trees go months without water, it can lead to desiccation and winter burn—even with Evergreens. Even in mild winters, New England winds can drain needles and bark. If the roots are in dry soil, they can’t replace the water they’ve lost.
2. Shaking snow can cause a vascular snap
Shaking or beating a branch with snow can cause vascular snap as well as microscopic cracks in the xylemand phloem (the tree’s circulatory system). To treat snow on branches, gently remove heavy, wet snow using an upward, sweeping motion with a broom to prevent breakage.
3. Overfertilizing can cause a cellular explosion
Applying nitrogen-heavy fertilizer in mid-winter encourages the tree to produce new, tender cells. A “January thaw” followed by a New England deep freeze can cause the water in those new cells to harden. This activity leaves trees with blackened “dieback” and a depleted energy reserve.
4. Wound paint creates a fungal incubator
Trees don’t heal; they compartmentalize (seal off) wounds using a process called CODIT. By painting the wound, you are essentially building a “greenhouse” for anaerobic bacteria and wood-decay fungi. Treating trees with dormant oils stops infestation.
5. Treating trees with dormant oils stops infestation
Some invasive pests, like the Hemlock Woolly Adelgid, have evolved a form of “biological antifreeze” in their systems. If you don’t treat them with dormant oils or mechanical scraping in the winter, their populations will explode.
6. Sap flow is a sign of positive root pressure
Trying to stop it is like trying to stop a healthy person from sweating. The “bleeding” helps flush potential pathogens from the wound. Using sealants alone interferes with this natural cleansing process.
7. Bark is living tree tissue
When the sun drops, bark can flash-freeze, creating a sunscald wound—a massive vertical strip of dead bark that can girdle and kill a young tree. Prevent sunscald damage by wrapping young trunks with white tree guards or burlap.
Questions about winter tree care? Contact experts at RITree. Or call (401) 764-5885. They’ll help you steer clear of winter tree care myths and boost the health of your trees.
Oils are often recommended as a “clean slate” treatment for professional arborists and eco-conscious homeowners. Oils are highly refined petroleum or plant-based products (such as mineral, canola, or soybean oil) used as non-toxic insecticides and miticides.
Applied to trees and shrubs during late winter to early spring, these oils are exceptionally effective against pests that “hide” in the bark over winter, such as aphids, mites, caterpillars, and scale insects.
Timing is critical with dormant oils. So is the weather. If you apply them too early, the pests aren’t active enough to be smothered; too late, and you can “burn” new leaves.
Temperature: Apply when the air temperature is between40°F and 70°F.
The 24-Hour Rule: Ensure temperatures will stay above freezing for at least 24 hours after application.
Dryness: Apply on a clear, non-windy day when rain is not expected for 24–48 hours to ensure the oil dries and sticks properly.
Not all trees tolerate oil well, however. Before spraying, check the label for these specific sensitivities:
Aesthetic Damage: BlueSpruce and Blue Junipers will lose their signature blue color and turn green. The oil dissolves the waxy “bloom” on the needles that creates the blue hue (it takes 1–2 years for new growth to restore the color).
Phytotoxicity (Tissue Burn): Maples (especially Japanese and Red), Black Walnut, Hickory, Beech, and Redbud are notoriously sensitive to oil and can suffer branch dieback if the concentration is too high or timing is off.
Chemical Conflicts: Never apply dormant oil within 30 days of a sulfur-based treatment, as the combination is highly toxic to plants.
Dormant oils protect trees from destructive pests by suffocating insects and their eggs before they hatch. Oils clog the breathing pores of pests like scale insects, mites, and aphids, stopping infestations in their tracks.
Applying them during the dormant season reduces the need for synthetic chemicals later on, safeguarding pollinators and beneficial insects inactive during winter. But they need to apply at the right time and the right amount.
See our blog post for more information on dominant oils.
Pruning fruit trees differs from pruning mature shade trees. Pruning fruit trees is a powerful management tool that ensures a consistent, high-quality, easy-to-harvest crop. It also maximizes fruit production and quality, improves light and air flow, and maintains the tree’s structural integrity and lifespan.
Here are six essential hacks for pruning fruit trees in winter:
1. Master the timing: late winter is best
Pruning cuts made too early in winter can create frost damage. Cutting closer to spring allows the wound to heal almost immediately when the tree breaks dormancy, reducing the chance of disease.
2. Start with pruning deadwood
Remove all deadwood and branches that show signs of disease or are broken. Also, prune branches that cross or rub against each other. They can create wounds that provide easy entry points for pests and diseases.
3. Open the canopy for sunlight and air
The primary goal of winter pruning is to create an open structure that allows sunlight and air to reach the tree’s interior. Create a “vase” or Christmas tree shape for peach, plum, and cherry trees by removing the central upright leader; create a central leader for apple and pear trees.
4. Use correct cutting techniques
Cut just outside the branch’s collar when removing a branch. When shortening a branch, cut just above an outward-facing bud, which directs the new growth away from the tree’s center, helping to open the canopy.
5. Prune to control vigor
Limit cuts to 10-20% of the wood if your tree is healthy and growing. If the tree is older and has minimal new growth, a more severe prune (up to 30-50% for stone fruits) can promote the growth of new, productive fruiting wood.
6. Use Sharp, Clean Tools
Sterilize your tools before pruning. Clean your hand pruners, loppers, and pruning saws with diluted bleach or rubbing alcohol to prevent the spread of pathogens between trees. Also, keep tools sharp.
Clean Up Immediately
Never remove more than one-third (33%) of the tree’s overall canopy in a year to prevent severe stress. Rake up and dispose of all the pruned branches and any diseased material. Leaving diseased branches or leaves on the ground allows pests and fungal spores to re-infect the tree the following spring.
The RI Tree Council offers an annual Fruit Tree Growing Course emphasizing a reliable, economical, and eco-friendly way to grow backyard fruit. The next class starts in March 2026. For more details, click www.ritree.org.
Large, mature trees, such as those listed on the RI Tree’s Champion Tree webpage, offer significantly greater benefits than smaller trees. Planting them, however, can be a challenge. Doing so in the fall reduces “transplant shock” and gives trees the best chance to establish roots before the stress of a full growing season.
Here arHere are seven tips for big tree care in the fall:
Clean up fallen debris Heavy piles of leaves or debris. Piles of branches can trap pests, fungal spores, and excess moisture, which may damage the tree’s base. Remove them. To ensure safety, have an ISA Certified Arborist perform a professional safety inspection, especially if the tree is near a residence, driveway, or utility line, or if you notice any sudden, large, exposed roots, or cracks in the trunk. They can recommend corrective measures like cabling or bracing to support weak limbs against winter weathere seven tips for big tree care in the fall:
1. Water trees deeply Water your trees thoroughly until the ground freezes. Even as temperatures decrease and leaves fall, trees still need sufficient moisture to prevent drying out. Focus on the root zone, which extends to the tree’s drip line (the edge of the canopy).
2. Apply a layer of mulch Apply a 2- to 4-inch layer of organic mulch, like wood chips or shredded bark, around the tree’s base. Keep the mulch several inches from the trunk to avoid moisture buildup, which can cause bark rot and disease.
3. Prune dead or damaged Branches Fall is ideal for pruning dead, diseased, or broken branches. Remove these hazards before winter storms and heavy snow to prevent them from falling and causing damage to people or property.
4. Inspect for pests and diseases Inspect the trunk and branches for signs of insect damage, fungal growth, or abnormal discoloration. Detecting problems early lets you plan necessary treatments before the spring growing season.
5. Fertilize if necessary Late fall is ideal for applying a slow-release, deep-root fertilizer, which helps feed the root system. Professional deep-root fertilization is often the most effective approach for large, mature trees.
6. Protect against trunk damage Protect the trunk from sunscald. Use a commercial tree wrap on the lower trunk or consider installing tree guards to prevent damage from rodents and deer rubbing their antlers. Remove the wrap in the spring.
7. Clean up fallen debris Heavy piles of leaves or debris. Piles of branches can trap pests, fungal spores, and excess moisture, which may damage the tree’s base. Remove them.
To ensure safety, have an ISA Certified Arborist perform a professional safety inspection, especially if the tree is near a residence, driveway, or utility line, or if you notice any sudden, large, exposed roots, or cracks in the trunk. They can recommend corrective measures like cabling or bracing to support weak limbs against winter weather.
Trees can adapt to different local conditions, significantly affecting tree growth, especially in New England. Seasonal changes, for example, in winter and summer in our area, can dramatically impact tree growth in urban areas. The right factors in the right amounts, however, can drive tree growth. Their interplay creates the character of New England’s forests.
Tree adaptations can be categorized as morphological (structural), physiological (functional), and phenological (timing of life events). Light intensity, water availability, and temperature, for instance, are critical physiological conditions and key factors that impact tree growth. Other key factors are soil nutrients, soil pH, soil aeration, competition from other plants, and disease and pests.
When selecting trees, consider the long-term effects of New England’s weather variability and climate change. Here are some tree species that are tolerant to New England conditions for growth:
· Red Maple (Acer rubrum)
This highly adaptable tree can tolerate many soil types and moisture levels. It can handle wet and dry conditions, making it resilient to fluctuations in precipitation. Red maples are also relatively tolerant of varying light.
· Red oak (Quercus rubra)
Red oaks are known for their drought tolerance, which is becoming more critical with changing precipitation patterns. They are also fast-growing and adaptable to many soil types. Remember that really high summer temperatures are not suitable for red oak.
· White Pine (Pinus strobus)
White pines adapt to many soil types and can tolerate some drought. They’re also relatively tolerant of wind, which can significantly impact New England’s changing climate. Plus, white pines can establish themselves in many locations.
The Eastern Redcedar (Juniperus virginiana) is very tolerant of harsh environmental conditions, including high heat, drought, and even salt spray, making it suitable for coastal areas. The Ginkgo (Ginkgo biloba) is remarkably tolerant of urban conditions, including heat, drought, and air pollution. While some non-native trees are adaptable, native trees generally provide better support for local ecosystems.
By selecting adaptable tree species and looking at the long-term effects of climate change, you can help ensure the health and resilience of New England’s forests for future generations. Being biocompatible with local conditions prevents widespread damage from pests and diseases.
New England is America’s second-most urbanized area, with more than 80% of its people living in cities. While cities provide New England residents with many benefits, they also experience higher-than-average temperatures and more intense heat extremes. A 2020 study, for example, showed that average temperatures in Providence’s less-vegetated neighborhoods could be more than 12 degrees hotter than well-vegetated areas like the city’s East Side. The increase is likely the result of the urban heat island effect (UHI).
Climate change often worsens the UHI effect, creating hot spots in cities lacking sufficient tree canopy density. As global temperatures rise because of climate change, a city’s baseline temperature increases, intensifying the already elevated conditions. Climate change also increases the frequency of heat waves, further intensifying the effect. Trees, however, are a natural solution to mitigating UHI. They help combat UHI by increasing a city’s canopy density, creating a cooler, more comfortable environment.
Factors Impacting the UHI Effect
Cities often become hotter than surrounding rural areas due to replacing natural land cover with heat-absorbing surfaces like pavement and buildings. These surfaces soak up solar radiation and release it as heat during the day, raising urban temperatures. Other factors influencing UHI include reduced vegetation/green spaces, city traffic, air conditioning, tall buildings, and narrow streets.
These factors can have profound effects on cities and urban residents, including:
• Increased energy consumption • Elevated air pollution levels • Higher heat-related illnesses • Increased respiratory issues • Decreased quality of life • Increased infrastructure risk • Increased ground-level ozone (smog)
UHI impacts those with the least access to financial resources and those dealing with additional health conditions more than other groups. For instance, seniors, children, and those with per-existing conditions are more susceptible to heat-related illnesses. It also impacts poorer communities, often with less green space and more heat-absorbing surfaces.
Keep in mind that average temperatures in some areas, however, vary from year to year. Even within a city, temperatures vary depending on proximity to the coast, green spaces, and the urban heat island effect. Plus, the Northeast can be pretty humid in the summer. Meanwhile, climate change isn’t helping.
Combating Urban Heating Island Effect
Combining UHI starts with having sufficient tree canopy—the layer of leaves, branches, and stems of trees covering the ground when viewed from above. It provides various cooling mechanisms that help reduce UHI, including evapotranspiration. This process triggers water uptake by roots and releases it through leaves, cooling the surrounding air and lowering ambient temperatures. A sufficient tree canopy also blocks solar radiation, reduces the heat absorbed by surfaces, alters wind patterns to provide cooling breezes, and reduces the surface temperature of pavements and roofs, among other things.
Tree canopy is a crucial component of urban planning. Some cities, however, lack sufficient canopy density. Tree canopy density in Warwick, Pawtucket, and Cranston, for instance, ranges from about 20% to 30%. Providence’s is more than 27%, with 3,221 acres of land and more than 415,000 trees. What’s the ideal canopy density? In the past, it was thought that 40% was the ideal goal density. Today, sufficient tree canopy depends on the context. What’s ideal for a desert city will differ from that of a city in a forested region.
Strategic Steps in Confronting UHI
The combined effects of UHI and climate change generate more intense heat waves and higher average temperatures in cities, boosting health risks and increasing energy consumption. As in Providence, increased investment in urban forestry initiatives is a key strategy for creating more resilient and sustainable cities in the face of climate change. Below are some steps cities can take to combat UHI.
• Species selection—Choose tree species that adapt well to the urban environment (e.g., drought-tolerant and pollution-resistant). Selecting tree species with large canopies and high evapotranspiration rates is critical. Key species include white oak, red maple, river birch, Gingko biloba, American hornbeam, Sweetbay magnolia, and Serviceberry.
• Tree Placement and Planting Design—This step requires strategic planting near buildings, streets, and other heat-generating surfaces. The goal is to create “urban forests” or green corridors to maximize cooling benefits.
• Urban Forest Management—Proper tree care, including watering, pruning, and pest management, ensures tree health and longevity. Community involvement in urban forestry initiatives also helps. See RI Tree’s website for more information on tree care.
The Urban Heat Island effect is a real challenge for some cities. Climate change isn’t making things any easier for these cities. Now is a good time to start thinking about combating these phenomena by increasing tree canopy. However, how much tree canopy you’ll need depends on where you live. Don’t focus on a specific percentage for tree canopy. Instead, assess your city’s needs, set realistic goals, focus on equitable tree distribution, and prioritize tree health.
Understanding the UHI effect, however, can lessen its impact on urban residents and the surrounding environment. Mitigating UHI is crucial for creating more sustainable and comfortable cities. Strategies like planting trees, using reflective materials, and designing buildings for better ventilation can help combat this growing problem.
For more information on how to boost tree canopy, feel free to contact one of our consultants at RI Tree.org.
Rachel Carson’s “Silent Spring” is proof that books can change the world. Published in 1962, this classic alerted us to the dangers of pesticides, especially DDT. Using science and facts, Carson shows that pesticides poison wildlife, contaminate food chains, and generate unforeseen consequences. It was a powerful and influential book that helped launch the environmental era. It makes for a compelling read.
Below are six books on tree care that have made an impact:
“The Hidden Life of Trees” by Peter Wohlleben: This book revolutionized public perception of trees, showcasing their complex social and emotional lives. It sparked a global interest in forest ecology and inspired a greater appreciation for the intricate workings of these vital organisms.
“The Nature and Properties of Soils” by N.M. Comber: Though not solely focused on trees, this book significantly advanced our understanding of soil science, a crucial factor in tree health and growth. Its impact on agricultural practices has indirectly benefited tree care and forest management.
“Arboriculture: Care of Trees, Shrubs, and Vines in the Landscape” by Michael Dirr: A foundational text in arboriculture, this book has educated generations of arborists and tree care professionals. Its comprehensive approach has significantly improved tree care practices worldwide.
“The Tree Expert” by John M. Harris: This classic text provides in-depth information on tree identification, physiology, pathology, and care practices. Its comprehensive information and practical advice make it an invaluable resource for professional arborists and home gardeners, empowering them with the knowledge they need to care for trees effectively.
“Arboriculture: Care of Trees, Shrubs, and Vines in the Landscape” by Michael Dirr: A foundational text in arboriculture, this book has educated generations of arborists and tree care professionals. Its comprehensive approach has significantly improved tree care practices worldwide. This list offers a diverse selection of books to suit different interests and levels of expertise. Whether you’re a casual tree lover or a professional arborist, these books can deepen your understanding and appreciation of these magnificent organisms. For more information on tree care books that make an impact, see our blog post on the subject.
Young trees are the key to a healthy, thriving urban landscape. But they face many
challenges in winter. Extreme cold can cause a tree’s tissue to freeze, split, and die. Newly planted trees are especially susceptible to extreme cold. Other winter challenges are desiccation (drying out), sunburn, rodents, and ice and snow damage.
Young trees are more vulnerable in winter than mature trees because of their thin bark, shallow roots, and lack of developed defenses. Here are some of the more severe winter threats to young trees:
Snow and ice damage
Freezing temperatures
Desiccation (drying out)
Sunburn (aka sunscald)
Rodent damage
Being proactive is the key to protecting young trees in winter. Use the seven actions below to take control of young trees.
Tree Wraps: Thin bark wrapped around the trunks of young trees protects them from sunscald and frost damage. Wrap your trees in late fall before the first hard frost.
Mulch—Apply 2-4 inches of mulch around the tree’s base, out to the drip line (the outermost edge of the canopy where water drips off the leaves).
Watering—Water young trees before the ground freezes. Well-watered trees are better equipped for winter. Don’t over water young trees; soggy soil can cause problems.
Pruning—Don’t prune in late fall or early winter. Prune in late winter or early spring when trees are dormant. Remove dead, diseased, or damaged branches and branches crossing or rubbing against each other.
Inspect trees—Look for pests or diseases and act accordingly. Winter is a great time to treat trees for specific pests that overwinter in the soil or on the tree.
Staking—You may need to stake some young trees. If you stake your trees, make the stakes loose enough to allow trunk movement in the wind. Make sure the stakes are about a foot away.
Snow Removal—Wet, heavy snow is bad for young trees. Gently shake the branches to remove excess snow. Don’t jerk or pull the branches.
Now that you know how to winterize young trees, be proactive and take steps now to protect them in winter. If you have questions about winterizing young trees, contact a registered arborist or one of our experts at RITree.
RI Tree recently announced the date and site for its Arbor Day 2025 celebration, which will be held at the Providence Country Day (PCD) School, East Providence, RI, on April 25th, starting at 11:00 a.m. The event includes a tree-planting ceremony on PCD grounds, lunch, speakers, and a Tree City USA Awards presentation to the host communities. Tulips, London planes, and elm trees will also be planted on PCD’s grounds as part of a school reforestation effort. This year’s celebration will be the state’s 139th. Arbor Day recognizes the importance of trees, which provide numerous benefits to residents, including purifying the air, helping cool the earth, boosting property values, and soothing the human psyche. Trees also beautify where we live, work, and play and slow and absorb storm-water, saving taxpayers millions of dollars in annual flood damage and treatment costs. For more details or questions about this year’s Arbor Day, contact RITree at 401-764-5885 or email ritree@ritree.org.
Disposing of Christmas trees after the holiday is a challenge. Many pros and cons exist for buying a real tree. Growing Christmas trees, for example, absorbs atmospheric carbon dioxide, which is good for the planet. Real Christmas trees are also renewable when sourced from sustainable tree farms. Plus, real trees are biodegradable.
Real trees also can be composted or chipped for mulch, returning nutrients to the soil. What’s more, buying from local sources supports local businesses. If you have an artificial tree, it can be used for many years, reducing the need for repeated tree purchases. Plus, it avoids the waste associated with single-use trees.
But real Christmas trees have downsides. Transporting them from farms to stores creates a significant carbon footprint. Trucks and other vehicles that burn fossil fuels are required to deliver the trees. Cutting down trees at a tree farm also contributes to deforestation if they are not responsibly sourced.
If improperly disposed of in landfills, real trees can decompose and release methane, a potent greenhouse gas. If you favor artificial trees, disposing of them involves high energy consumption and using harmful chemicals. If made from plastic, they can be challenging to recycle and often end up in landfill.
Disposing of Christmas Trees Responsibly
Which approach is better? It all depends. Ultimately, the most environmentally conscious choice depends on individual circumstances and priorities. Ideally, you want to minimize your environmental impact by buying trees from reputable sources or buying sustainably produced artificial trees. Use your Christmas tree for as long as possible, and then dispose of your tree properly. Below are some tips on doing that.
Here are several options that involve giving your Christmas tree a new role:
• Use it as firewood —You can cut it up and use it as firewood. But the wood may still be wet, so use it only in an outdoor fire pit and only when the wood is dry. Using it indoors otherwise is a fire hazard.
• Recycle it as winter mulch—Leave the tree in your yard for the winter. It can provide much-needed shelter for small animals and birds. In the spring, chop it up and use it for mulch.
• Make it a bird feeder — Place it in its stand outdoors. Then, fill some bird feeders and hang them from the tree’s boughs. You can also drape the tree with a swag of pine cones coated with peanut butter.
• Protect plants with it — The winter is hard on tender plants. Cut a few branches or boughs from the tree and cover your tender plants for the winter. The branches will protect them from the season’s harshness.
• Add Christmas freshness to your home — Strip the tree’s pine needles and make a sachet of them. Then, hide them around the bathroom and kitchen for some cheerful fragrance.
Additional Tree Disposal Options
Many Rhode Island cities and towns offer curbside pickup during designated weeks in January. This option is easy, but check your local municipality’s website or sanitation department for pickup dates and guidelines. Providence, for instance, will collect trees on its regular trash pickup day in January. Check with the Department of Public Works for when the program starts and ends. The pickup period ran from January 3rd to 20th last year.
Remove everything from the tree before putting it out. The Rhode Island Resource Recovery Corporation (RIRRC) has an online guide with detailed information on when cities and towns pick up trees. You can also bring the trees directly to the Johnston facility. RIRRC grinds the trees and adds them to a composting operation that produces 40,000 tons annually.
Trees for Trout Program Another popular option is to donate the tree to the Rhode Island Department of Environmental Management (DEM) Division of Fish and Wildlife for its Trees for Trout program. RI DEM partners with Trout Unlimited Rhode Island Chapter on this program, which uses donated trees to build fish habitats in rivers and streams. This effort restores the water bodies and gives trout and other aquatic animals a place to hide from predators. The next collection event for the Trees for Trout program is on Saturday, January 4th, 2025, from 10 am to 2 pm at the Arcadia Check Station in Exeter, RI. You can find more information about the program on the DEM website or the Rhode Island Chapter of Trout Unlimited website. Christmas is a great time of the year. But once it’s over, you must do something with your tree. If your municipality provides that service, you can always put it on the curb for trash pickup. But if that option doesn’t appeal to you, you can use the tree better by giving it another role. Use the tips above to make that happen.
