Grass and trees are not always the best of friends. 

In natural settings, the ground around large shade trees is covered with leaves. As the leaves decompose, they release nutrients which the tree needs. Not so in our cities where are trees are surrounded by grass. The grass actually competes with the tree for water and nutrients.  

How you care for your lawn can affect the health of your elm tree.

Fertilizing  
Scatter fertilizer around a tree and you will end up with very healthy grass. Tree food stakes inserted into the ground release nutrients below the grass layer. Use fertilizers specifically designed for shade or elm trees.

Mowing  
Take care when mowing. Lawn mowers can damage a tree. Better yet, avoid the problem by keeping the grass back from the base of the tree. A buffer zone of loose soil or mulch is ideal.