The objective of this study was to describe compost establishment factors in a new compost bedded pack barn. The barn had 2 bedded areas (Side 1: 557 m²; Side 2: 595 m²) bedded with kiln-dried sawdust at a 38.1 cm minimum depth. Three 6.1 m diameter high volume low speed fans hung above each bedded pack. The lactating herd was moved into the compost bedded pack barn on April 21, 2016. Bedded areas were tilled twice daily with a rototiller (45.7 cm depth) at milking time. Daily samples were collected at midday, until July 7, 2016. Bedding samples were collected from each pack at the center of 9 equally distributed sites using a 59.1 cm² scoop. Bedding temperatures were collected from these same areas using an infrared thermometer for surface temperatures and an analog probe thermometer for temperatures at 10.2 cm and 20.3 cm depth. Hourly weather data were collected from a university weather station. Descriptive statistics were prepared using SAS Version 9.3 (Table 1). Mean (mean ± SD) stocking density throughout the study was 11.8 ± 0.6 m² per cow for side 1 and 12.4 ± 0.7 m² per cow for side 2. Within 16 d of cattle being housed in the compost bedded pack barn, composting temperatures on both sides exceeded 43.3°C at 20.3 cm depth (accepted minimum compost temperature). Carbon content decreased and nitrogen content increased consistently throughout this same period, indicating sufficient composting of bedding and animal waste. Table 1. Bedded pack and barn descriptive statistics from a 2-sided compost bedded pack barn

Variable	Day 1			Day 15			Day 30			Day 77 (final)
	Side 1	Side 2		Side 1	Side 2		Side 1	Side 2		Side 1	Side 2
20.3 cm depth temperature (°C)	18.3	20.8		34.4	37.9		46.7	52.0		50.6	50.9
10.2 cm depth temperature (°C)	19.0	21.0		28.3	32.5		41.8	45.0		44.5	47.4
Surface temperature (°C)	19.0	21.0		9.2	10.9		20.8	20.1		25.0	25.5
pH	5.0	5.3		7.9	7.7		8.8	8.6		8.5	9.2
Moisture (%)	8.0	8.0		35.0	34.0		36.0	40.0		31.0	40.0
Carbon (DM %)	48.5	48.4		45.6	45.2		37.5	41.4		23.6	30.0
Nitrogen (DM %)	0.1	0.1		0.4	0.5		0.7	0.9		1.0	1.4
Mean daily air temperature (°C)	19.3 ± 3.0			9.3 ± 2.4			15.2 ± 2.4			24.4 ± 3.0
Mean daily relative humidity (%)	64.1 ± 18.2			80.6 ± 10.4			83.2 ± 11.9			82.3 ± 10.1
Mean daily wind speed (m/s)	2.9 ± 1.5			5.1 ± 2.8			3.2 ± 2.0			2.7 ± 1.2