Native Plants As Habitat For Wildlife - Native Plant Society of ...

Winter Twig and Shrub Identification Workshop
Anna Leighton
Winter identification of trees and shrubs is based primarily on the buds that grow on the 6
inches at the end of a branch - the area of last summer’s growth. Other surface features
such as prickles thorns and bark texture are also used. Berries and fruits are useful in
some groups but most fleshy fruits disappear in winter, so the buds are a more reliable
feature for mid-winter identification (although a number of these also get consumed by
animals and birds).
Looking at buds on bare twigs will help you identify different kinds of shrubs (i.e.
genera) but will not always allow you to separate species. In spite of this, a surprising
amount can be learned about the landscape by looking at trees and shrubs after their
confusing leaves are gone.
BUDS - The two things to look for are the
arrangement on the branch and bud characteristics.
Arrangement. This is easy to see with the naked eve.
The buds will be either alternate or paired. When
paired they are called opposite.
Characteristics
Bud scales - The bud is tightly covered with
scales to protect it from drying out in winter. If you
look closely with a lens you can seethe overlapping
edges of these scales and can estimate how many
there are. If you see no overlapping edge, there is
probably only one scale that fits like a cap over the
bud.
Leaf scar - underneath every bud there is a
scar where the leaf that grew under the bud detached
in fall. This is called a leaf scar. The shape of this scar
and the number of dots (called bundle scars) on it are
useful in identification.
Position of the terminal bud - Another key
feature is whether the bud at the end of the branch is
centred on the tip (a “true” end bud) or is offset a
little to the side (a “false” end bud).
THORNS and PRICKLES - These features persist in
winter and are useful for separating certain groups so
you should know the difference between them.
Thorns are actually woody growths of the
stem and are very firm and deeply seated in the
branch. Prickles are more fragile outgrowths of the
bark and can be removed with it.
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