PT  - JOURNAL ARTICLE
AU  - Shigo, Alex L.
TI  - Branches
AID  - 10.48044/jauf.1980.073
DP  - 1980 Nov 01
TA  - Arboriculture &amp;amp; Urban Forestry (AUF)
PG  - 300--304
VI  - 6
IP  - 11
4099  - http://auf.isa-arbor.com/content/6/11/300.short
4100  - http://auf.isa-arbor.com/content/6/11/300.full
SO  - JOA1980 Nov 01; 6
AB  - Trees have developed effective defense systems for walling off infections that may enter the trunk through dying and dead branches. As the growth rate of a branch decreases, the trunk wood begins to form a swollen collar around the base of the branch. When pruning, cut as close as possible to the collar, but do not remove the collar.