

In Florida many of these growths are a result of a fungal infection from Sphaeropsis tumefaciens. Plants in the Florida Keys affected by this disease include oleander, gumbo limbo and green buttonwood. On some of these plants the symptoms produced are a knotty gall.
Control: To deal with infected plants prune branches at least six inches below where symptoms are seen. Prune during dry times, dip pruning tools in a 10% bleach solution between cuts. Infested pruning shears can rapidly spread the disease. Severely infected plants should be removed & destroyed. No chemical fungicides are available to control witch’s broom.
For more information:
okeechobee.ifas.ufl.edu/…/witches.broom.htm
okeechobee.ifas.ufl.edu/…/witches.broom.htm
These links were updated in May, 2011.
Photo credits:
Kim Gabel, UF/IFAS