Aggressive poplar suckers could be a job for an arborist
Q Our neighbours next door have huge poplar trees that send roots into our yard. Our lawn is covered with suckers from these roots which are about five to 10 centimetres deep. One summer we tried digging out the roots which caused considerable damage to the lawn. This year we tried using an axe to hack the suckers out from the roots but, within a week, the suckers have grown again. Is there anything else we can do to prevent these roots from sending up suckers?
A This is a very difficult problem to deal with and I feel your frustration. Using a chemical solution such as a non-selective herbicide like Round Up is not a good idea because you can actually permanently damage the mother tree.
For every shoot you see coming up from the ground there are many more buds waiting to spring up below the surface. Sometimes the runners can be cut away as you have done and it solves the problem. Other times just mowing can control the issue. In your case it sounds more severe. A targeted root excision might be the best way to handle this problem. This really is best left to a professional tree company and arborist who knows what they are doing in order to not damage the mother tree.
Q We have an Amur maple tree, approximately 40 years old, in our yard. In the last couple of years, it's been dropping its leaves starting in late June through July. The leaves turn yellow and have black spots on them. We rake up the fallen leaves as soon as they fall. Would you have any solutions to stopping this problem?
A Once again I'll call on my friend and retired plant pathologist Dr. Ieuan Evans to give us the definitive diagnosis.
“Tar spot is common on Amur maple but it does little to really affect the health of the tree,” was his response.
According to the University of Guelph, “The disease is already widespread and sanitation (leaf removal) is not effective in reducing the infestation level for the following year, so let the leaves decay under the trees to at least improve the soil health.”
There is disagreement on this method as Dr. Evans suggests raking up the leaves. If it were me, I'd also rake up the leaves as not only does it remove a possible source of the fungus spreading to other trees but also improves the esthetics of the area.
Q I had to cut down my very large 18.3 metre mountain ash trees late last fall. At that time, I had to pot up some of my plants so as to make way for the arborist. I then counter sunk the pots in the tree mulch for the winter. I am slowly in the process of redoing some of my back yard, as most of my yard is planted with shade plants. The potted plants are mostly hostas, and a couple of astilbe. I have them on my deck for now, but sadly, I will not be able to plant them again as I get too much sun now. Can hostas be over wintered in pots in my heated garage? If so, what is the best way to store them? Should I give them a bit of water occasionally as they will not be in a frozen state?
A I was saddened to read about the removal of your enormous mountain ash trees — they must have been spectacular. Hostas in a heated garage will work just fine and, yes, giving them the odd drink will be helpful so they don't dry out. Don't overwater, just give them enough to barely moisten the soil.
Every week, Growing Things Outdoors runs online at edmontonjournal.com or, if you prefer an epaper format, epaper.edmontonjournal.com. Learn more by emailing your questions to filipskigerald@ gmail.com, reading past columns or my book Just Ask Jerry. You can also follow me on Twitter @justaskjerry01.