There has been a lot of discussion on when, where, and how to prune hops correctly - its a hot topic.
I am posting this pic to show the consequence of pruning without taking into account the varietal differences.
Variety Nugget- "bull" with no crown buds
This is a 2 1/2 year old Nugget that was cut late fall of 2011 at 1" above the soil line; removing the visible crown buds. Nugget is a hybrid variety that has been selected to produce just a few main primary crown buds; which are formed quite high on the plant stem. It was watered and fertilized normally all throughout the past summer and fall. This pic was taken in the first week of February, 2013. The plant root system has survived intact (didn't increase in size, though). Note there are still no crown buds visible! Will it ever resprout? Not sure - there a nodules forming slowly on the upper roots that may be bud or rhizome primordia. Point to be made is that if a whole hopyard of Nugget were pruned too short; the yield would be drastically reduced for more than one season.
Lynn, the head hop grower at Great Lakes Hops has over 30 years of experience in the horticultural field. Browse the blog articles here to find useful growing information for humulus lupulus, based on personal experience and observations at Great Lakes Hops.