winter injury plant material maintenance. temperature fluctuation damage can occur from: ...
Post on 19-Dec-2015
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Winter Injury
Plant Material Maintenance
Temperature Fluctuation
Damage can occur from:Rapid/extreme fluctuations in tempExtended mild weather can de-acclimate
plants, leaving them vulnerable to rapid temp drops
Low Temperatures
Use USDA Hardiness Zone RatingSeveral mild winters can lull people to believe
plant will be hardy. (Cutleaf Japanese Maple) Plant marginally hardy plants in protected
sites. East side of buildingcourtyards
Frost Cracks
Long cracks on the south-southwest side of thin barked treesDue to temp fluctuations between day and
night; uneven contraction of the woodEx European Linden, Red Maple, Norway
Maple
Frost Cracks on Green Ash
Sunscald Injury Very similar to frost cracks; damage is an
elongated cankerWinter sun is lower in the southern skyThe lower angle of the sun can directly heat
the south and southwest side of a tree trunk during a sunny winter day
Subsequent freezing, night-time temperatures damage cells
Thin barked trees w/ smooth, dark bark are particularly susceptible
Sunscald on the SW side of a Chokecherry tree
More Sunscald Injury
Winterburn on Evergreens
Browning or scorched needles Due to desiccation
Winter sun & wind dries leavesTranspirational water lossReplacement water unavailable (frozen)
Can apply an anti-desiccant to prevent injuryReapply throughout winter
Snow & Ice Breakage
Heavy snow and snow piled on plants from driveways and walks
Multi-stemmed evergreens most prone to damage
Gently remove heavy snow from branches Do not remove ice from ice-encased
branches
Help Me!
Salt Damage
Damage appears in spring and early summer Scorching of leaves
Avoid heavy salt usage near plants Use salt tolerant plants near walks and drives if
salt needed. Most salt damage occurs from late winter
applications of salt. Avoid if possible. Use calcium chloride, or other safe de-icer,
instead of rock salt
Girdling by animals
Mice/rabbits/voles feed on bark and girdle branches. Growth beyond girdling dies in spring
Wrap trunks with screen wire or hardware cloth
Minimizing Winter Injury
Select hardy plants Avoid late summer pruning and fertilizing Water plants during dry periods until ground freezes Use mulch to conserve moisture and insulate roots Protect evergreens with screening Use anti-desiccant if needed Wrap trunks to protect and remove in spring Use safe ice-melting products
The End