A few years ago, as I was talking with a local nursery owner, she told me she had an abundance of hops that she had planted some time back and offered me as many as I could use. She couldn't remember what variety they were, but said they were ordered by a customer who was a home brewer and never picked up. It was getting close to hop harvest time, so I asked her to bring in a sample. I went to the nursery the next day and determined that they weren't quite ready to harvest. A week later she had another sample that looked and felt ready. I rubbed and sniffed and they had a mild citrusy aroma. The cone size and shape was similar to Cascade. I got a couple of buckets full and brewed a Pale Ale, using them at 60 (figuring 5% AA), 1/2 lb.in a 30 minute whirlpool, and another 1/2 lb. for dry hops.
The resulting beer was very pleasant, but really didn't have any characteristics that led to confidently pinning down the hop variety. I took a few bottles to my local LHBS on learn to brew day. Some of the local craft brewers were there and sampled the beer. They all thought it to be a great Pale Ale, but none were able to confidently identify the hops used. We all agreed that Cascade and Cluster were strong possibilities, but the growing conditions had not produced hops that were typical to either variety.
For an IPA, I think a neutral bittering hop is the way to go.
