Special class of the commoners were "ulijars". They were the bee keepers and collectors of the bee products on the feudal lordships. "Ulijar" had a duty to take care of the apiaries ("ulijanik") which belonged to rulers, monasteries, churches or lords, and was relieved of all other feudal duties. It is recorded that during the establishment of the monasteries, the rulers would sometimes, among other gifts, donate "ulijaniks" with "ulijars" to take care of them. The bee keepers were much sought in this period as need for the bee products, especially the wax needed for the churches, was great and growing all the time. Also, honey and wax were expensive export goods. As "ulijars" were giving the 10% tribute in the products, that wasn't nearly enough for the entire state, so the number of "ulijars" grew. The Hilandar Monastery administered 15 apiaries throughout the state. "Ulijars" mostly lived within the agricultural settlements or outside of the villages, on the monastic properties suitable for the bee keeping, but a rare, small settlements consisting solely of the bee keepers also existed.