Question
I have a bed of roses that came with the house we bought last spring. They are mostly long stem hybrids (we live in Mississauga just outside Toronto) The soil is a 70% clay 30% dirt mix in the beds going into solid gray clay at about 10-12". The roses are against the building facing southwest with sun 65% of the day (morning though noon) They all came up looking wonderful. I had covered the root stems last fall in mulch and cleaned them back down to the center root in the spring. In the last 3 weeks "something" has happened and it's hit all 9 plants. Some worse than others. Starting at the bottom and working up, the leaves are just dying and falling off, some all the way to the buds and even the buds are going brown before they open. It's like they have been poisoned. I stopped watering them weekly thinking that they might be getting too much water, but this evening I dug down 12" and the solid was pretty dry...dryer than I'd like. So I don't know what is going on. The ONLY other thing I can tell you is that my wife decided to put a wood chip ground cover down on the beds. It's dark black so I know the chips have been treated with something, but these things are designed for garden beds so I assumed they'd do not wrong to the roses. Could creosote be the issue? Or is it something else? I have had tones of afeds but I gently remove them each morning and evening. I have not used Bayer or sticks. My next step was to dig an 8" radius out from each plant, 12" down and replace all the soil around the upper roots with a blend of triple mix and dark earth. Any other thoughts?

cheers
Doug

Answer
Roses are capable of fooling you into thinking they are alive and growing well. They do it by using up the moisture left in the dying canes. Then they suddenly stop growing well and start to die but thy were half dead already. From your description it does sound like your roses were activated into growth with something over the winter. Usually  wood mulch is just plain fir, spruce or hemlock ground up.  It sounds like it is the type  they cook with fish discards. If that is what it is, then the nitrogen in the mulch kept the roses growing. The other thing  this type of mulch does ( if it is the added to type of mulch) is that it is hot because the cooking starts a re-action and it acts like a compost and as you know compost piles can get really warm. The black colour suggests to me it is one of those mulches. Which by the way are excellent if they are put on but not close to the rose canes.
Because you are trying to save dying rose bushes I would do drastic measures such as pull the mulch away from the roses,  prune the roses right back to clean wood even if it means going down to  a few inches, no fertilizers, as the roses are under stress and the roots won't be working properly, if they start again and grow well I would only use a fish fertilizer on them as chemical fertilizer is too harsh on frail roses. Give them and the area all around the base a spray with a fungicide such as Orthos Rose Pride of any other one that are just a fungicide not anything else in them. Combination sprays are very harsh on roses.
They have done tests on creosote and because the wood is not soaked but simply dipped in the chemical, they have found no reason not to use it. Some gardeners don't like the idea of using it on their vegetable beds but again no proof it isn't a wisdom to use it. I guess there is not enough of the chemical on the wood to leach out.