In Veliki Orehek, in co-operation with Institute for the Protection of Cultural Heritage, Basic Unit Novo mesto, 8 hayracks were chosen for dendrochronological research. Dendrochronologically dated hayrack pillars are made from oak (Quercus sp.) or chesnut (Castanea sativa) wood. The wood from Vic's double hayrack was dated in year 1900, which confirms that it was built in 1908 as engraved in the wood. Vic's single stretched hayrack with coat was built or reconstructed after 1939. It also contains the recycled wood of older objects dated in year 1834. Pipan's single stretched hayrack with coat was probably built in the period from 1887-1897 as supposed by dating of 3 pillars. One pillar of the coat, dated in 1859, possibly originates from an older object. Majac's single stretched hayrack with coat was dated in year 1966, but the pillar of the coat was dated in 1881. Stravs's single stretched hayrack with coat was built from 1862-1872. Meznaric's double hayrack is made of wood from 2 periods, one dating in 1789 and the other in 1860. Jure's single stretched hayrack was dated in 1964. All analyzed hayracks are still in use. Most of them have been renovated, and they are relatively well preserved. All of them are recorded in the Register of real cultural heritage of the Republic of Slovenia.