I have a dealer installed block heater on my tractor. As I remember it is in the 400 to 600 watt range. It works great. I usually plug it in for at least an hour before starting the tractor. I have started my tractor twice this winter without plugging in the heater for at least an hour first. The engine starts fine without the heater being used but the noise it makes is quite remarkable (loud and banging) compared to a warmer start. Also the exhaust is much smokier with the cold start. Many tractor owners on TBN say there is no need for a block heater. That's OK but doesn't change my opinion. I use one on my truck and it's quite noticeable how much quicker the engine produces heat to clear the frost off the windshield and warm the cab. The tractor temperature gauge comes off dead cold quickly when I have used the block heater. I don't bother plugging in the heater if the temperature is 'just' in the lower teens F at night but when it gets down to below zero it really makes ME feel warmer when I hear how the engine sounds when first started.
I have seen those mini bales of straw for sale in lots of craft stores and at vendor booths at horse shows. I never gave it much thought about the machine used to bale these novelty items. But I have noticed you can buy a full sized bale for what these mini bales cost.
Tom