[CANUFNET] To Mulch or Not To Mulch

[terri smith]

I would like to know if there are any municipalities that have stopped applying mulch on newly planted boulevard trees.  Current research indicates that mulch should not be placed over the root ball because it causes roots to grow up into the mulch area, it also causes roots to remain within the root ball area instead of growing out laterally, and it actually prevents the water from penetrating deep into the soil.  Dr. Ed Gilman and Dr. Hannah Mathers both agree that no more than 2 – 2.5 inches of mulch should be applied outside of the root ball area (if mulch is still going to be applied) and both are in agreement that mulch provides no benefit to the tree.  At 2 inches of mulch there is little to no weed suppression.
 
These new findings contradict our current mulching practices and have created much debate within our department.  I would like to hear from other municipalities that have either discontinued mulching or have never mulched their blvd trees.  Is there a need to increase the amount or frequency of watering?
 
Terri Smith
Urban Forestry
City of Saskatoon 		 	   		  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://list.web.net/pipermail/canufnet/attachments/20110330/69b0c5e2/attachment.htm>