Chelan
A very high-alpha hop with an extremely high percentage of beta acids. A daughter of Galena, this variety is similar to Galena in terms of analytical data. Samples were not available in time for press.
Chinook
Chinook is a very high alpha hop which, for some reason, has gained a reputation for having a rather rough character. My experience shows that its bitterness is just as smooth as many hops of much lower alpha acid. Chinook has a pleasant, but intense aroma: slightly spicy and very piney. They are like a cross between Saaz and a pine forest. Substitutes: For bittering, a high-alpha hop, such as Eroica, Galena, or Nugget. For aroma/flavor, the pine-like character is unlike any other hops, however Southern Cross has both spicy and piney character although in different proportions. Sticklebract is quite piney also. Saaz, Crystal and Tettnanger would give a similar type of spiciness as Chinook.
Cluster
Cluster is used primarily as a bittering hop, but can give a nice black currant aroma and flavor. Substitutes: Brewer's Gold for flavor and aroma; for bittering, I would use Chinook, Galena, Eroica, or Olympic.
Columbia
Columbia is an obsolete high-alpha U.S. hop that, was derived from Fuggle and another hop derived from Fuggle. The aroma is said to have been similar to Fuggle. Substitutes: Fuggle, Willamette.
Columbus
Columbus is a U.S. high alpha hop that has a very low cohumulone level. It has an intense, citrusy hop aroma rather similar to Cascade and Centennial. It also has a slight woody character. Columbus is the only hop used in Anderson Valley IPA. Substitutes: For bittering, Nugget and Chinook would be reasonable. For aroma/flavor, Cascade, or Centennial.