Vertical Mulching In a forest, trees are constantly helping to create soil and mulch by their annual  leaf drop. Leaves that fell 5 to 10 years ago are now decomposed into rich top soil and the leaves that have now just fallen provide a thick cover of mulch. This is the natural environment in which the fibrous root system thrives and gathers water and nutrients necessary for good health. Thick grass, mowing, and  leaf raking work in direct opposition to this natural system. And, let's face  facts. If you have contracted with a lawn care company to guarantee a thick turf, free of broad leaf weeds, your valuable trees become the "biggest" broad  leaf weed problem in your lawn. Trees are still affected, usually more slowly  than smaller broad leafed weeds, by the various lawn care herbicides. Vertical mulching is a time-tested method of overcoming the stresses trees face in the  unnatural environment of the area. It creates columns of rich "top soil" down past the grass roots and deep into the area where tree roots can take advantage of them. Several years after vertical mulching, a careful examination of one of  the columns would show thousands of tree feeder roots flourishing there. And,  vertical mulching is the perfect opportunity to fertilize your trees. Many local trees, especially maples, oaks and ash, have been brought back almost from the brink of death from vertical mulching properly done. However, do not expect to  see instant results. Trees are usually slow to die and slow to respond to  treatments. It might be a year or more before the foliage thickens and gets its rich color back. To properly vertical mulch, you will need an electric or gasoline-powered drill and  a 2" or 3" diameter auger. These tools are easily available from any tool rental company. Starting 8 feet away from the trunk, drill holes on 3 feet centers 15"  deep. Discard the soil that is removed from the hole. Back fill the holes using  a 50/50 mixture of peat moss and course sand or pea gravel.   A  - Field of holes on 3 foot centers allows air and water easy access past grass  roots to tree roots. Watch out for underground utilities.   B  - Since the root system does not stop at the dripline, often it is best to  vertical mulch beyond. You  could also use turface or vermiculite. Add 6 ounces of 10-6-4 or 12-12-12 granular plant food to each hole. Late fall or early spring is the ideal time to  vertical mulch. The  holes should cover at least the area shaded by your tree at high noon. The  feeder roots grow at least 25% beyond the drip line. If this area includes your  neighbor's yard, get his permission to drill on his property.   Note: Always know where your underground utilities are before drilling. In Ohio, call Ohio Utilities Protection Services (1-800-362-2764). There is no  charge for this service.   C  - Fill each hole with mixture of fertilizer, coarse sand and organic  matter.