Mulching Trees and Shrubs
As I look around charlotte, I see lots of mulched trees. Probably 98% are mulched improperly. Mulch should only be put no more than 3 to 4 inches deep depending on the size of the tree and possibly the species. The reason is that the purpose of the mulch is keep the soil cool, retard evaporation, reduce weed growth, and keep lawn mowers and other equipment away from the trunk and exposed surface roots. Good quality mulch such as wood chip mulch will decompose and shrink over a year or two. Pine needles which are very acidic will not decay very quickly and tend to be piled too high. Mulch that is to deep will often retard water by not letting the water get to the soil below.
The second big error I see is that the mulch is piled up at the trunk of the tree. Mulch should be kept back at least 6 inches from the base. Moisture will accumulate at the contact of mulch and tree trunk harboring insects and possibly allowing fungal and bacterial organizims an entry point into the tree.
I have a large willow oak in my back yard and initially decided to mulch around the tree out about 20 feet from the trunk. That didn't look good so I brought the mulch in to about 4 feet from the trunk. This looked much better. Photo of this tree is below and also shows the excellent root flare.XXXXX photo here
We don't see it so much in our part of the country, but pea gravel, seashells, river rock, are often used as mulch. Rocks absorb heat and smaller pebbles will work their way into the soil and create maintenance problems. Bottom line would be to try to replicate what Mother Nature does.
Below I have placed some photos of poor mulching practices.
Freedom Park willow oaks along entrance way into the Park. Sugar Creek would be to the right. The mulch is too deep and is up touching the trunk. Because the tree is growing in a tight area between the curb and the pathway, the trunk sometimes grows upward. The main objection is that the mulch is too deep and is up next to the trunk
I have a large willow oak in my back yard and initially decided to mulch around the tree out about 20 feet from the trunk. That didn't look good so I brought the mulch in to about 4 feet from the trunk. This looked much better. Photo of this tree is above and also shows the excellent root flare and protects the tree from lawn mower damage. I will post a second picture.
more photos already taken, will post later.