Effect of azolla in composting of tree bark, tea wasts and rice hull m.n. padasht dehkaee, a. khalighi, a. kashi and r. naderi cxollege of agriculture, university of Tehran

The present investigation was carried out in the Department of Horticulture, College of Agriculture, Tehran University in Karaj, to study the effects of Azolla in composting of tree bark, tea wastes and rice hull and to compare the physical and chemical properties of mixes and organic matters with media standards for use on the ornamental plants. At first, Azolla ferm were mixed with tree bark, Tea wastes and rice hull as volume ratios of 0%, 25%, 75% and 100%. The mixes were sampled, during composting in 45 and 90 days, for maturity determination. The experiment was designeed in Randomized Complete Blocks, with four replications. After five months, the mixes were sampled again, and compared with control mix consisted of 50% peat and 50% perlite. At this time all physical and chemical properties were measured. Results showed that Azolla alone, did not significantly affect rice hull in composting, but in 50% and 75% ratios significantly affected composting of tree bark and tea wastes. Azolla compost was rich in nutrient elements, and tree bark compost and its mixes with Azolla had the best properties for ornamental plants media.