The cultivar 'Arapaho' is particularly susceptible. Be sure to periodically inspect any new plantings or old plantings with a history of the disease this spring. Look for plants with small or spindly shoots with pale yellow-green leaves. Later in the spring, bright orange pustules will form on the underside of the leaves. These spores are blown to and infect healthy leaves.
Orange rust colonizes the shoots and roots of infected plants.
Once infected with the rust, the plant remains infected throughout its life. Immediately dig up and destroy plants with orange rust. The fungicide Nova was recently labeled for control of orange rust on brambles. However, this product is used to prevent infection of healthy plants, not eradicate the fungus from systemically infected plants. If you have had a problem with orange rust and are considering using Nova, please contact me for details on fungicide timing.