Question
One rose stem at a time is dropping it's and then die. Later another stem does the same thing. We have numerous roses around the house. The same thing goes on.
 We live in Tacoma WA 98446.

Answer
I don't know whether or not I have enough information to give you a sound answer. Because the problem is effecting not one but many of your roses, it has to be something that was done to all. If a gardener sprays the lawn with a herbicide even though there is no wind, the spray has a nasty habit of still floating on the air. If the spray hits a rose, the leaves will start to curl up and then die, then the cane dies and finally the whole plant. Even chemical fertilizer or a fertilizer spray will effect roses if it is done in the heat of the day. If the roses were just planted, then it could be in the soil. If they have been in the soil for some time that would not be a problem. An insect called a cane borer gets in after a cane has been pruned and eats out the centre of the cane which causes the leaves plus the canes to die. If you could describe how the leaves are dying that would narrow it down for me. Thanks.