Sightings of red band needle blight prompted Forestry Commission Scotland and Confederation of Forest Industries to swing into action.
Infections at two nurseries, Christie Elite Nursery and Christies of Fochabers, were found in August. This followed clean bills of health at both sites on earlier inspections. A third site, the commission's Newton Nursery, has also been hit.
The "position statement" sets out the measures Forestry Commission is taking for the blight, which it calls the most significant disease of coniferous trees in Britain.
Infected and nearby stock amounts to five-million pine plants at these nurseries. Other stock further than 550m away from the nearest known infection can be traded as normal.
The statement describes the background of the disease: "Present since the 1950s, it was first recorded in Scotland in 2002 and has caused extensive damage including mortality to some Corsican and Lodgepole pine stands."
Growers have agreed to destroy nursery beds with confirmed infection and managers are keeping an eye on risks.
Meanwhile, scientists are looking at the distribution of the two fungal pathogens - Dothistroma septosporum and Dothistroma pini - that cause the disease.