164 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 15 



tional work, the disease is caused by eel worms. When the disease 

 is found in a bed, the diseased bulbs, all the healthy bulbs in the vicinity 

 as well as the earth are removed and burned. Experiments have 

 proved that the soil can be freed from the disease if bulbs are not planted 

 on the same land for a ntimber of years, but the value of the bulb land 

 prevents this; furthermore, it takes years for the complete disintegra- 

 tion of all parts of the affected bulbs. Dr. Van Slogteren also stated 

 that experiments with heating bulbs in warm water at 40° C. for a number 

 of hours killed the eelworms and did not injure the propagating quali- 

 ties of the bulbs ; further experiments in connection with the effect on 

 the forcing qualities are now being carried on. 



Meredon sp. is reported as being rarely a serious pest but it does occur 

 occasionally however in fields that are too well protected by wind breaks. 



BosKOOP. This is the centre of the ornamental trade and approxi- 

 mately two thousand acres are devoted to the growing of nursery stock. 

 Previous to the war this acreage was divided among three hundred nurs- 

 erymen, the majority of whom were small growers. There aie now about 

 twenty large firms in the district, holding from ten to fifty acres and up, 

 of land. About one hundred and fifty firms do a direct export business 

 and the remainder sell their plants to the larger firms. The nursery 

 industry was first started in this district two hundred years ago. The 

 nurseries are laid out in narrow strips, between canals, averaging 150- 

 300 feet wide and from one-quarter to a third of a mile long. They 

 appeared in most excellent condition, were free from weeds and no sign 

 of either the gipsy or brown tail moths were seen. 



Plant Inspection Service. The organization of the Phytopatho- 

 logical Ser\dce has been outlined in a special bulletin prepared by the 

 service' so it is unnecessary to consider it in detail at this time. The 

 nurseries are inspected frequently throughout the summer, and in- 

 structions are issued to the growers to spray or carry out any other 

 treatment when such is considered necessary. If the instructions 

 are followed a "general certificate" is issued to the grower, without 

 which he may neither dispose of his stock locally nor secure an export 

 certificate. Written records of all certificates are kept, and if for any 

 reason a grower can not account for all the certificates forwarded to him, 

 no additional certificates are issued until a satisfactory explanation is 

 furnished. In the Boskoop district the local government requires the 



'The Phytopathological Service in the Netherlands, No, 13, 1921. Wageningen, 

 Holland. 



