Ring of trunk tissue that surrounds a lateral branch at its point of attachment to the stem
Merriam-Webster Online Dictionary
collar (noun)1.
a band, strip, or chain worn around the neck as
a) a band that serves to finish or decorate the neckline of a garment
b) a short necklace
c) a band placed about the neck of an animal
d) a part of the harness of draft animals fitted over the shoulders and taking strain when a load is drawn
e) an indication of control a token of subservience
f) a protective or supportive device (as a brace or cast) worn around the neck
g) - clerical collar
2.
something resembling a collar in shape or use (as a ring or round flange to restrain motion or hold something in place)
3.
any of various animal structures or markings similar to a collar
4.
an act of - collaring arrest capture
transitive verb
1.
a) to seize by the collar or neck
b) - arrest grab
c) to get control of - preempt we can collar nearly the whole of this market Roald Dahl
d) to stop and detain in unwilling conversation - collar the guest of honor
2.
to put a collar on - collar a dog