suckers
By Harvey
west mids,
United Kingdom 
the sucker on the robinia tree has grown at the same rate as the tree since planting (3 years) now approx 6 ft tall.
the sucker bears no flowers, but the rest of the tree bears flowers. would i be safe to cut off the sucker at ground level. ?
17 Jun, 2008
Answers
I have big Robinia (false Acacia) trees. They grow a lot of excess growth at a low level that gets in our way so we slash them back a lot. They are very vigorous and don't mind being chopped, so I guess yours won't mind either. If they are genuine suckers then the usual treatment is to pull them off right down at the bottom where they emerge from the stump.
18 Jun, 2008
If you just chop it off, it thinks it has been pruned and grows vigorously. That's why you have to pull it off under the soil - not cut, as Chris and Nosey said. not an easy task, but necessary.
18 Jun, 2008
Previous question
my friend grows bonzis and the best way to get rid of the sucker is to rip it down and of .you will end up with more to in the future if you dont.sounds brutal but you get all of the sucker like that.
18 Jun, 2008