Take fire blight seriously. Ask about ZPb2
Fire blight is an extremely infectious plant disease that can cause the rapid death of a large number of trees. The primary host plants are Malus, Pyrus, Sorbus, Amelanchier and Crataegus. Owing to special buffer zones, the chance of infection and spreading is very slight. But nurseries that are located in such a buffer zone do not automatically have fire blight free plants.
Look for the ZPb2 Plant passport
The creation of buffer zones is a good way to combat the spreading of this disease. The Nederlandse Plantenziektekundige Dienst (Netherlands Department of Plant Diseases) makes absolutely certain that there are no instances of fire blight in the buffer zone. Communal green areas and nurseries in the buffer zones are given a thorough inspection. The nurseries that pass this severe inspection are allowed to display the ZPb2 Plant Passport. This passport guarantees that the plants are free from fire blight and that the bacteria isn’t even present in latent form.
No inspection, no ZPb2
Maintaining the buffer zones costs a lot of money. Previously, the inspection costs were paid by the state in the Netherlands. Since a number of years, the inspection costs must be borne by the nurseries that are located in the buffer zones. Not all nurseries are willing to do this. Consequently, they are not allowed to export any plants to countries that require the ZPb2 certificate. As customer, it is important for you personally to make sure that a nursery can guarantee a fire blight free delivery.
Van den Berk Nurseries can provide all its trees with the ZPb2 Plant Passport. 
