Garden Q&A: How do I deal with trees that shoot up suckers?

Whether you're a gardening beginner or expert, Irish Examiner columnist Peter Dowdall has the answer to your questions

Rhus typhina or stag's horn. 

QUESTION

I have two trees that are shooting up suckers all over the bed they're in. 

I cut them back last year and this year they seem to be spreading further again. 

Can you advise on what to do?

ANSWER

Suckers are shoots that emerge from underground buds along a root system. 

Many plants are very prone to suckering and this is how they spread, for example, Rhus typhina or stag's horn. 

Irish Examiner gardening columnist Peter Dowdall. Picture: John Allen

This isn’t a problem if you know this before planting and only plant these trees in an area where you have space to allow it to spread. 

Some trees such as the variegated poplar will send up suckers up to 100 metres away from the parent plant. 

The root system of such trees is extremely vigorous and cause serious problems to pipework and even house foundations as the roots travel in search of water. 

In answer to the question, there is little enough that can be done to stop a root system from producing suckers if it is prone to doing so and thus you may need to remove the offending tree if suckers are causing a problem. 

If suckers are only around the base of the tree then they shouldn’t be a problem.

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