Regarding a tiller, the short answer is no.
The longer answer is probably not.
The explanation is that the tiller needs 540 RPM to operate. At 540 rpm pto speed in first gear on an N ground speed is about 3.23 mph. Much to fast for a tiller.
The exception would be if the N had a Howard auxiliary transmission (about $1200 these days) to slow the ground speed while maintaining 540 rpm pto speed. Another exception that has been mentioned is sandy, loose soil & putting the tractor in neutral & letting the tiller push the tractor.
Bottom line.....unless you can actually test it on the soil you plan on tilling, I'd stick w/ the short answer, above.
I have no clue about a snow blower. (I live in VA!)
Regarding a phd, I fenced my 3 acre pasture as well as my neighbors 2 acres w/ a phd on my N's. Success w/ a PHD on an N depends on soil type & trees.
I've got very sandy soil, no rocks & no trees. But, once the ground got rock hard w/ no rain in 6 weeks, no more digging. Remember, 23 hp, hydraulics up, gravity down. And, no reverse on the phd, so when you auger it in, you will learn all the tricks to get it out!
Doesn't matter what you use to pull a wagon loaded w/ hay if it's going down hill & the load weighs more than the tractor. No hills around here either & I've never counted the square bales, but it's can carry a lot.
No manure spreaders around here either other than the neighbor kid w/ a fork.
What it does best is plow w/ a two bottom plow, disc w/ a 5 or 6' disc, run a 5' bush hog or a 6' finishing mower.
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