Thanks to all, especially Dovefromabove. Our garden is sheltered but we fed the roses as directed by both Gardener's World and the RHS. However, given the unusual conditions in May that may be what happened.
@d.horler Have the roses been sprayed with anything I. E Rose clear, or an insecticide? Have you given them a leaf fertilisation feed I. E seaweed, Epsom salts etc via an overhead watering? The canes look healthy, which rules out fire blight.
No, we never spray our garden with anything other than water. When we feed the garden and plants, we do so by watering can (it's a small garden!) or mulch. The roses themselves seem to be flowering well and the only sign of distress is the leaf condition. I hope that when we cut them back later this year, they will recover their full vigour and have new leaf growth as normal.
I agree with Borderline... that is rose sawfly damage.. very severe in your case, but it's been one of those Springs where so much has survived winter.. so these kinds of problems are more prevalent than we would normally find..
I don't think it's sawfly because the plant has not been defoliated by the caterpillars, the leaves have completely dried out and dropped off; they are on the ground around the plant itself. If it was sawfly then the leaves would have been eaten.
The large Rose Sawfly do eat the leaves up and are more active into the summer months, but the Rose Slugworm, often missed because they are not eye catching in colour and quite small, they do cause similar looking damage to those seen on your original photograph.
But, as you say, your roses are still flowering away and the leaves seem to have dropped off because they are dried up and a husk, they can be pruned away, and hopefully in time, your roses may leaf up again.
@d.horler ...if you keep doubting, then you cannot be helped.. ...some photos very similar to what you have, at the bottom of this page, and lots of information...
Marlorena, I don't keep doubting. I have enough experience to know that it is not common sawfly. I have experienced that condition several times before and I know it's not that. The leaves are not eaten at all, they are brown and dry. My wife and I regularly check for sawfly and I am 99.9 percent certain it is not that.
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Have the roses been sprayed with anything I. E Rose clear, or an insecticide? Have you given them a leaf fertilisation feed I. E seaweed, Epsom salts etc via an overhead watering?
The canes look healthy, which rules out fire blight.
But, as you say, your roses are still flowering away and the leaves seem to have dropped off because they are dried up and a husk, they can be pruned away, and hopefully in time, your roses may leaf up again.
...if you keep doubting, then you cannot be helped..
...some photos very similar to what you have, at the bottom of this page, and lots of information...
http://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/pests-and-problems/insects/sawflies/rose-and-pear-slugs-sawflies.aspx