Do you think yours are looking bad, bearing in mind your horrid hot summer? Suspect the advantage of a nice thick mulch may well have offset any change in soil PH. Roses are very tolerant of PH (more or less, there are a few picky ones). It is also harder, I find, to sustain an enhanced acidity than it is to change the PH to more alkaline, at least in the longer term.

I've used it before and know of others who do all the time and I can't recall there being any problem with it.

It's nonsense. Make a note not to listen to that person.

Thank all of you for your quick respone, I will quit worrying about the Pine bark mulch.

It's really not the nitrogen loss from the bark that may cause any problems as mulch. I found through some research that some pine needles are allelopathic and inhibit the uptake of nitrogen for other plants. Not all pines.

I turns out the pines that grow in our forest just happen to have the allelopathic pine needles and I have collected the needles and used them to mulch between my propane tank and the garden shed. They have controled the weed infestation in that awful area.

Smiles,
Lyn