Replacing City trees that have died


Hi. As you know the City of Toronto plants a tree in every front yard. My brother had a 60+’ high Little Leaf Linden that died in his small front yard. Since it was a city tree the city cut it down and left a very low to the ground stump which they are going to grind out. A new city tree has to be planted in the front yard but here lies the question: Can you plant the new tree right in the spot that the old stump is ground out or do you have to plant in an area away from the stump regardless of the fact that it was ground out?
Love to know your thoughts.
Thanks. – A


I’m sorry to hear about the linden! I’m not sure which tree will be selected for your brother’s yard, but the city provides a number of options – see Toronto Street Tree Guide. Your brother can submit a preference as to tree species, if he wishes.

No, it is not recommended to plant a new tree right over the ground stump. Instead, the planting hole should be at least 1 metre (3.3 feet) from the old stump material, to make sure the new tree has lots of space to grow and send out its roots. Even if much of the sawdust created by grinding is removed from the yard (I’m not sure if the City will remove it), there may still be roots of the old tree left in the ground, occupying space a new tree would need.

As well, the new tree should be planted into fertile soil that has a good supply of nutrients to support the tree’s growth. Sawdust, if left behind, changes the soil’s structure and nutrient balance. The ground stump material will have a high ratio of carbon to nitrogen, which could decrease the amount of nitrogen available for the new tree. Water retention by the sawdust could also reduce adequate soil drainage.

It’s not clear why the linden tree died. If due to a pest or disease, this could be a concern for the new tree, even if planted a few feet away from the stump hole. If this is the case, the City should be aware, and provide a tree that is not susceptible to whatever killed the linden.

If, for some reason, the new tree must be planted in the same spot as the dead linden, experts recommend:
• Wait a minimum of 1-2 years to plant a new tree, to ensure the roots of the old tree have decomposed.
• Ensure the site is adequately prepared – remove the stump and all sawdust created by the grinding. Chop/remove as many roots as possible, then fill the planting hole with compost and good soil to give the new tree a chance to establish.

Note, too, that I did not find any literature to suggest that the below-ground roots left behind by a linden could be toxic to other trees.

This is a terrific question, one that may be of interest to many gardeners. I hope the new City tree will be healthy and happy for many years to come!