Are My Trees and Shrubs Dead or Dormant? 5 Ways to Tell
In mid to late winter, we cross our fingers that our bare trees and shrubs endured the seasonal extremes and any late cold blasts, merely resting before spring’s warming conditions. During this quiet time in the landscape, it can be difficult to discern a dormant plant from a dead one. Garden expert Katherine Rowe explores visual and physical cues to hone in on the viability of your dormant tree or shrub.
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Dormancy is an evolutionary secret power as a survival technique for plants to conserve resources during seasonal variations. Temperature and resource scarcity drive the rest period after the active growing season.
Many deciduous species enter winter dormancy, where roots withstand cold conditions while upper growth remains unexposed without the need for additional resources. Others experience summer dormancy, where they drop leaves in hot and dry weather to conserve energy and moisture. Dormancy is also a stress response during extreme drought, heat, heavy frost, etc. Seasonal fluctuations may cause a delay in emergence.
In dormancy, processes like water and nutrient uptake and photosynthesis slow or diminish, reducing the plant’s needs. Growth is inactive and requires the right conditions to emerge. For winter dormancy, increasing warmth and moisture initiate awakening, while cool, mild autumnal weather signals summer-dormant species to flush.
This restorative dormant period allows a rest before producing new growth, flowering, and fruiting (reproducing). As we await spring in cool climates, it’s challenging to differentiate between a tree or shrub that’s dormant or one that didn’t survive winter. Here, we’ll explore visual and physical cues to look for in hopes of a spring flush.
Bend or Break?
Examining the stems is an easy way to determine if the tree or shrub is dormant or dead – or maybe partially damaged. Healthy stems are pliable with a degree of bounce-back. Dead, dying, or damaged branches crack easily under a snap of the wrist.
Choose a small stem to test its quality. If it’s brittle and breaks easily under your grip, it’s not viable for growth. The interior tissue will be dry and tan or brown in color. A living stem offers flexibility, and while it may bend or break under pressure, the interior will be pithy and white or green. The turgid stems show moisture is present and flowing through the tissues.
If you have dead stems, it doesn’t mean the entire tree or shrub is dead. Woody shrubs like hydrangea and roses may experience dieback from winter conditions. Winter damage may isolate to a few canes or may comprise the entire crown, though the roots may be alive. Test the stems and cut them back to healthy growth in late winter (or to the ground if all parts of the stem are dry). Wait to see if new growth emerges from the crown as spring unfolds.
Some species are slow to emerge and require warm air and soil temperatures, so give them time to pop up before pulling them. If all branches of a tree are dead, it’s likely not going to recover. If the roots are alive, they may send off suckering shoots that result in a weakened form in the long term.
Scratch Test
Another simple method to check if a tree or shrub is dead or dormant is a scratch test. Using clean pruners, a blade, or your fingernail, choose a branch and lightly scratch a small spot of the surface bark away. Removing the outer layer exposes interior tissues. The cambium is the growth layer and should be light or bright green. If you encounter brown, dry material, the branch isn’t supporting growth.
Test multiple branches. If you reach living tissue, prune stems to a node in the healthy portion. New growth will emerge from the nodes if the plant has strong roots for recovery.
Disinfect Tools
Trees and shrubs are susceptible to bacteria, fungi, and viruses that spread easily through tools during pruning sessions, even a scratch test. A good first step early in the season is to sterilize pruners and other tools to limit the spread of common diseases, especially if the selection in question isn’t dormant but has a disease or virus.
A simple alcohol wipe on the blades does the trick. A solution of rubbing alcohol (70% or higher concentration of isopropyl alcohol) works as a quick dip.
When it comes to tool selection for pruning, sharp bypass hand pruners, and long-handled loppers are best for precise cuts. Sharp tool blades ensure clean cuts, free of shredding or tearing stem tissues, which can cause weakness and susceptibility to pests and diseases.
Check the Buds
The next step is to inspect any buds along branches and at the end of the stems. The apical buds are the growth tip or the primary point of growth for the branch. Apical buds are cone-shaped at the stems’ terminus. Healthy buds will be well attached. Dead ones drop easily, are dry, or may not be present.
While trees withhold water from the buds in winter to protect them from freezing, prying gently into a young, undeveloped bud should reveal a hint of green. If the buds aren’t healthy, inspect the branches for viability and pruning needs.
Overall Health
In addition to a close inspection of stems and buds, it helps to step back and look at signs of overall health. Look for diseased branches or those that show cankers, holes, and crevices. These can be signs of insect and disease damage, sometimes followed by woodpecker activity on trees or fungi visibility growing in decaying areas.
Check for fresh wounds that may need a clean cut to accelerate healing. Shedding bark and aged branches are natural processes, but a lack of regenerating bark or new growth indicates a decline. For mature specimen trees, an assessment by a professional arborist is good practice if health is in question.
Root Inspection
If you’ve tried the other measures and are considering pulling the specimen, investigate the roots (easier for shrubs than trees). Do this as soils are workable on a mild day to minimize stress and root disturbance in case of viability. Dig beyond the drip line or root ball to look for healthy feeder roots and those on the perimeter. Feeder roots lie just below the surface to seek water and nutrients.
Healthy roots should be white or light in color. Those experiencing root rot or that are no longer supporting growth will be brown and possibly mushy. For recent transplants, you may find they never grew beyond their initial pot size due to underlying problems or cultural conditions. You may also uncover pests like larvae that do extensive damage as they feed.
Ways to Boost Winter Survival
While trees and shrubs suited to our hardiness zones are often adaptable, setting them up for success over the winter ensures the best results. Borderline specimens and those in containers benefit especially.
Mulching
Mulching adds all-season protection. Add a two to three-inch layer of mulch to add insulation, regulate soil temperatures, suppress weeds, and retain moisture. Mulching helps protect roots during frost heaving when soils naturally freeze and thaw due to temperature and moisture changes.
Leaf mulch, leaf mold, weed-free straw, compost, bark, and aged wood chips are good options. A spring and fall round keeps mulch thick but light while allowing natural degradation and soil enrichment as it breaks down.
Water Through Fall Frost
Deciduous trees and shrubs that enter dormancy rely on moisture leading into winter. Normal moisture supports turgidity (water-filled roots, stems, and leaves) and strengthens tissues against frost damage by allowing stress-free natural processes to continue until dormancy. Watering before winter protects against sunscald and fluctuations at the cellular level.
Evergreens like hollies and conifers, too, need it to support foliage and roots and prevent winter browning. Hearty roots and less stress entering the cool season are the foundation for successful overwintering.
Wrapping and Extra Insulation
In areas with frigid winters, newly planted trees benefit from extra protection. Trees from one to five years after planting are contenders for trunk wrapping. Wrapping their trunks helps keep them insulated. A special tree wrap material or kraft paper wound around young trunks prevents them from splitting with fluctuating temperatures and sunscald from exposure.
Borderline hardy shrubs like roses and hydrangeas benefit from added protection in zones 6 and lower. Mound a layer of leaves over the crown and roots in dormancy. A wire cage filled with leaves (chicken wire or similar) forms a cylindrical frame and insulating cushion to last all season. Wrapping with frost cloth can help during temperature extremes and cold snaps. Remove extra coverage in late winter or early spring before new growth emerges.
Preventative Pruning
Pruning contributes to long-term health and improves resistance against winter injury. The goal of preventative pruning is to direct growth to retain a sturdy structural form.
Prune out dead, diseased, or crossing limbs any time of year. Leave big cuts and structural decisions for trees to professional arborists. Stop any pruning by late summer to avoid generating new growth. Tender stems are susceptible to weakness and winter dieback, potentially damaging the limb in freezing situations. Pruning deciduous trees during dormancy allows full visibility of structure and form while growth is inactive. Pruning when dormant doesn’t promote new growth until temperatures warm.
Key Takeaways
- Test the stems for pliability and pith.
- Do a scratch test to assess the cambium.
- Inspect the apical buds.
- Look for signs of pests and diseases.
- Check root conditions.
- Prune branches to a healthy node or to the ground if not present.
- If unsure, take a wait-and-see approach to reassess later in the season.
- Provide extra protection next winter for vulnerable species.
