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Modern dairy farms generally have two manure streams, solid and liquids. The solid manures come from the maternity stalls and calf barns while the liquid manures (85-90% moisture) come from free stall barns. This paper reports results of controlled outdoor full scale windrow studies under Ohio's weather conditions using both the solid and liquid dairy manure waste streams. Studies included: a) TW, turned windrows/ natural convection/ no cover, b) TWA, turned windrows/ controlled aeration/ no covers and c) TWC, turned windrows/ natural convection/ covered. Volume and weight reductions as well as dry matter, moisture and nitrogen losses during composting were presented as functions of composting time. Results for dairy manure (free stall) mixed with sawdust or straw using the TW method showed weight losses and volume losses of over 80% the compost mix. Normalized to the original manure weights and volumes, reductions from composting were 77% w/w and 42% v/v with the sawdust amendment and 76% w/w and 57%v/v with the straw. TWA studies using oxygen levels to set aeration patterns showed increases in total weight, water and nitrogen loss. Results on dry matter and C loss were inconclusive. Results for TWC studies showed covering the windrow with a fleece blanket during composting reduce rates of dry matter loss and nitrogen. Over a 77 day composting period, %C loss was 54% versus 38 % while N loss was 18% to 4% for uncovered vs covered, respectively. Results suggested that moisture loss would be increase with covers. This result was believed due to covers shedding rainfall