The list below is a cheat sheet for hop varietal characteristics and was pilfered from bear-flavored.com. In a couple weeks I'll start adding notes to it as well to start rounding it out and provide some more details (beta acids, myrcene, caryophyllene, etc.). Additional details will be sourced from "From the Love of Hops" by Stan Hieronymus and from the Hop Union website.
Admiral (UK)
AA Range: 13.5 - 16%
Characteristics: Bred as a replacement for Target with a less harsh bitterness. Weak aroma with mild citrus character.
Substitutes: Target, Challenger
Ahtanum (US)
AA Range: 5.7 - 6.3%
Characteristics: Citrus and floral character, with grapefruit qualities said to be stronger than in Cascade. Ahtanum may also feature resiny or earth notes.
Substitutes: Cascade, Amarillo
Amarillo (US)
AA Range: 8 - 11%
Beta: 6 - 7%
Cohumulone: 21 - 24%
Characteristics: Floral, grapefruit, citrus, peach.
Substitutes: Cascade, Centennial, Citra
Apollo (US)
AA Range: 18 - 22%
Beta: 5.5 - 8%
Cohumulone: 24 - 28%
Characteristics: Orange, with some resin. Dank.
Substitutes: Summit
Aramis (US)
AA Range: 8%
Characteristics: Herbal, floral, earthy, lemon.
Substitutes: N/A
Aurora (Slovenia)
AA Range: 7 - 9%
Characteristics: General "hoppy" aroma, fruity.
Substitutes: Styrian Golding, Premiant, Northern Brewer
Belma (US)
AA Range: 12%
Characteristics: Clean fruity hoppiness; strawberry, melon, mild citrus. Click through for my experience with Belma in a single hop IPA.
Substitutes: Pacific Gem
Bramling Cross (UK)
AA Range: 7 - 10%
Characteristics: Strong and spicy English hop. Fruity blackcurrant and lemon citrus.
Substitutes: East Kent Goldings, Progress, Brewer's Gold
Bravo (US)
AA Range: 14 - 17%
Characteristics: Smooth, mild flavor; fruity, floral. Clean bittering.
Substitutes: Warrior
Brewer's Gold (UK)
AA Range: 5 - 8%
Characteristics: Early bittering hop. Resiny, spicy. Black currant aroma.
Substitutes: Bullion, Galena, Bramling Cross
Bullion (US)
AA Range: 7 - 9%
Characteristics: Early, traditional bittering hop for stouts. Resiny, earthy; pungent black currant or raspberry aroma.
Substitutes: Brewer's Gold, Galena
Calypso (US)
AA Range: 12-14%
Characteristics: Lemony aroma, tart apple, earthy tea.
Substitutes: n/a
Cascade (US)
AA Range: 4.5 - 7.0%
Beta: 4.8 - 7%
Cohumulone: 33 - 40%
Characteristics: Ubiquitous American hop; citrusy grapefruit character.
Substitutes: Centennial
Centennial (US)
AA Range: 9 - 12%
Beta: 3.5 - 4.5%
Cohumulone: 28 - 30%
Characteristics: Balanced fruity citrus / stone-fruit character. Smooth bitterness.
Substitutes: Cascade, Citra
Challenger (UK)
AA Range: 6 - 9 %
Characteristics: Clean bittering hop with strong, spicy aroma.
Substitutes: Perle, Target, Phoenix, EKG
Chinook (US)
AA Range: 11 - 14%
Beta: 3 - 4%
Cohumulone: 29 - 34%
Characteristics: Spicy, piney flavor with some grapefruit.
Substitutes: Nugget, Columbus, Northern Brewer
Citra (US)
AA Range: 10 - 12%
Beta: 3.5 - 4.5%
Cohumulone: 22 - 24%
Characteristics: Potent aroma of intense mango, tropical fruit and citrus. Flavor is a bit smoother, less specific but still intense. Extremely effective as a dry hop and late addition hop. I've heard complaints about Citra as a bittering hop
Substitutes: Galaxy, Centennial, Nelson Sauvin
Cluster (US)
AA Range: 5.5 - 8.5%
Characteristics: Pungent bittering hop; spicy, floral aroma. One of the original American hops.
Substitutes: Galena, Northern Brewer
Columbus / Tomahawk / Zeus (CTZ) (US)
AA Range: 14 - 16%
Beta: 4.5 - 5.5%
Cohumulone: 30 - 35%
Characteristics: Dank, earthy, resin.
Substitutes: Chinook, Nugget
Comet (US)
AA Range: 9 - 11%
Characteristics: Intense wild American grapefruit / citrus character; extremely dank.
Substitutes: Summit
Crystal (US)
AA Range: 2 - 5%
Characteristics: American grown Hallertau hybrid. Flowery, spicy aroma. Sister hop to Mount Hood and Liberty.
Substitutes: Mt. Hood, Hersbrucker, Liberty, Hallertau
Dana (Slovenia)
AA Range: 11 - 16%
Beta: 4.8 - 6%
Cohumulone: 28 - 31%
Characteristics: A psuedo-Noble hop with a rustic, musty spiciness and mild bitterness.
Substitutes: N/A
Delta (US)
AA Range: 5.5 - 7%
Beta: 5.5 - 7%
Cohumulone: 22 - 24%
Characteristics: Slightly spicy with a hint of citrus. (Delta is a cross between Fuggles and Cascade). Described as subtle and mild.
Substitutes: N/A
East Kent Goldings (UK)
AA Range: 4.5 - 6.5%
Beta: 1.9 - 2.8%
Cohumulone: 28 - 32%
Characteristics: A popular, traditional English hop with gentle fragrant aroma. Smooth, spicy and floral. Has defined English ales for centuries.
Substitutes: Fuggle, First Gold, Williamette
El Dorado (US)
AA Range: 14 - 16%
Characteristics: An intense, candy-like aroma of cherry, pear and fruit. Can taste like cherry Jolly Ranchers in extra-hoppy beers.
Substitutes: Sounds pretty unique, sorry folks
Falconers Flight (US)
AA Range: 10.5%
Characteristics: Tropical, citrus, floral, lemon and grapefruit.
Substitutes: Cascade, Ahtanum, Sorachi Ace
Falconers Seven Seas (US)
AA Range: 9 - 10%
Characteristics: Fruity, citrus, spicy, earthy. A cross-breed of 7 "C" variety hops. (Get it?)
Substitutes: Simcoe
First Gold (UK)
AA Range: 6 - 9%
Characteristics: A child hybrid of Goldings, similar in aroma; spicy. Woody, minty flavor and aroma.
Substitutes: Eat Kent Goldings, Fuggle, Crystal
Fuggle (UK)
AA Range: 4 - 6%
Characteristics: Woody, earthy. Mildly spicy.
Substitutes: Williamette, Styrian Goldings
Galaxy (AUS)
AA Range: 13 - 15%
Beta: 5.8 - 6%
Cohumulone: 35%
Characteristics: Tropical passionfruit, citrus hints of peach, mango. Similar to Citra but more fruity, less dank. For notes on my Galaxy single hop IPA, click here.
Substitutes: Citra, Amarillo, Centennial
Galena (UK)
AA Range: 11 - 14%
Characteristics: Fruity black currant; citrus.
Substitutes: Legacy, Brewer's Gold, Nugget
Glacier (US)
AA Range: 5 - 6%
Characteristics: Earthy/floral character with a sweet citrus.
Substitutes: Williamette, Styrian Goldings
Green Bullet (NZ)
AA Range: 10 - 14%
Characteristics: Fruity, resiny; described as having a distinct raisin-like character.
Substitutes: Possibly Galena
Hallertau (GER)
AA Range: 3.5 - 5.5%
Beta: 3 - 4%
Cohumulone: 17 - 24%
Characteristics: Versatile, classic hop with mild spicy, flowery, earthy aroma. "Noble" hop common to German lagers. See also: Hallertau Mittelfrüh
Substitutes: Hersbruck, Mt. Hood, Liberty, Helga
Hallertau Aroma (Wakatu) (NZ)
AA Range: 7 - 9%
Beta: 5.8 - 8.5%
Cohumulone: 28 - 35%
Characteristics: Less spicy than Mittelfrüh, with a floral and citrus / lime character. Also known as Wakatu.
Substitutes: N/A
Hallertau Blanc (GER)
AA Range: 9 - 12%
Characteristics: Flowery-fruity aroma, passion fruit, grapefruit, gooseberry and pineapple.
Substitutes: Sounds like it could be the German response to Galaxy / Nelson Sauvin?
Hallertau Mittelfrüh (GER)
AA Range: 3.5%
Beta: 3.5 - 4.5%
Cohumulone: 20 - 26%
Characteristics: Versatile, classic hop with mild spicy, flowery, earthy aroma. "Noble" hop common to German lagers. Most likely a regional subset of Hallertau hops.
Substitutes: Hersbruck, Mt. Hood, Liberty, Helga
Helga (AUS)
AA Range: 5 - 6.3%
Beta: 4.6%
Characteristics: Noble-ish aroma, flowery, mild. (I like that the few sites I've found with this hop describe it as "good for Ales and lagers." Gee, thanks.)
Substitutes: Hallertau Mittelfrueh, Hersbrucker
Herald (UK)
AA Range: 9 - 13%
Characteristics: A sister of Pioneer; strong bitterness with citrus and grapefruit.
Substitutes: Pioneer
Herkules (GER)
AA Range: 12 - 17%
Characteristics: Slightly fruity, spicy aroma.
Substitutes: Horizon, Magnum, (Hallertau) Taurus
(Hallertau) Hersbrucker (GER)
AA Range: 2 - 5%
Beta: 4 - 6%
Cohumulone: 19 - 25%
Characteristics: Moderate-intensity floral character, spice and fruit.
Substitutes: Hallertau, Helga
Horizon (US)
AA Range: 10 - 16%
Characteristics: Citrus and floral, fragrant aroma. Possibly some spice / resin. Clean bittering.
Substitutes: Magnum, Amarillo
Hüll Melon (GER)
AA Range: 6.9 - 7.5%
Characteristics: Strawberry and honeydew, melon nuances.
Substitutes: N/A
Kohatu (NZ)
AA Range: 6 - 7%
Beta: 5.8 - 3.5%
Cohumulone: 21%
Characteristics: Intense floral characters, grapefruit, pine needles, tropical fruit.
Substitutes: N/A
Legacy (US)
AA Range: ~7 - 8%
Characteristics: Floral, blackcurrant, spicy.
Substitutes: Cluster, Galena
Liberty (US)
AA Range: 3 - 6%
Characteristics: Mild, slightly spicy, resiny. Sometimes considered a noble hop.
Substitutes: Hallertau
Lublin (Poland)
A Polish-bred descendant of Czech Saaz.
Marynka (Poland)
AA Range: 7 - 10%
Characteristics: Earthy, rooty, liquorice.
Substitutes: Perle, Chinook
Magnum (GER)
AA Range: 11 - 15%
Characteristics: Very clean bittering with mild, faint aroma.
Substitutes: Horizon
Mandarina Bavaria (GER)
AA Range: 7 - 10%
Characteristics: Intense mandarin, citrus notes.
Substitutes: N/A
Meridian (US)
AA Range: 6 - 7%
Characteristics: Not much info on this one yet; I've read that Meridian offers citrus, lemon, with some tropical fruit and floral characteristics.
Substitutes: Citra, Amarillo, Sorachi Ace.. ?
Merkur (GER)
AA Range: 12 - 15%
Characteristics: Similar to Magnum for bittering, but with an earthy, floral aroma.
Substitutes: Magnum, Horizon
Millennium (US)
AA Range: 13 - 16%
Beta: 4.8%
Cohumulone: 30%
Characteristics: Clean bittering, with herbal aroma.
Substitutes: Nugget
Mosaic (US)
AA Range: 10 - 12%
Beta: 3.2 - 3.9%
Cohumulone: 24 - 26%
Characteristics: Mango, stone fruit, berry medley, melon. Mild herbal character reported in some instances. Click through for notes on my Mosaic single hop IPA.
Substitutes: Possibly a blend of Galaxy and Nelson Sauvin
Motueka (NZ)
AA Range: 6.5 -7.5%
Characteristics: Lemony, tropical fruit, spice.
Substitutes: Saaz
Mount Hood (US)
AA Range: 5 - 8%
Characteristics: Mild and clean aroma and flavor.
Substitutes: Hallertauer, Tettnanger
Mount Rainier (US)
AA Range: 5 - 8%
Characteristics: Hallertauer with higher AA; aroma of citrus and licorice.
Substitutes: Hallertauer, Fuggles
Nelson Sauvin (NZ)
AA Range: 11 - 13%
Beta: 6 - 8%
Cohumulone: 22 - 26%
Characteristics: White wine, grapefruit, tangy berries. Dank and intensely fruity. Click through for notes on my Nelson single hop pale ale.
Substitutes: Extremely unique, no subs.
Newport (US)
AA Range: 12 - 15%
Characteristics: Mild aroma; good bittering.
Substitutes: Magnum
Northdown (UK)
AA Range: 6 - 10%
Characteristics: Clean bitterness and a distinct woody, minty flavor.
Substitutes: Northern Brewer
Northern Brewer (UK)
AA Range: 8 - 10%
Characteristics: Good bitterness and neutral, mild flavor.
Substitutes: Northdown, Perle, Aurora
Nugget (US)
AA Range: 10 - 14%
Characteristics: Somewhat heavy, herbal bitterness and aroma.
Substitutes: Galena, Columbus
Opal (GER)
AA Range: 8 - 10%
Characteristics: Moderate bitterness, spicy, fruity, floral.
Substitutes: Saphir, East Kent Goldings
Pacific Gem (NZ)
AA Range: 13 - 16%
Characteristics: Clean bitterness; soft flavor with notes of strawberry, blackberry, berry medley. Tangy citrus, melon, tangerine. Click through for notes on my Pacific Gem single hop pale ale.
Substitutes: Belma
Pacifica (NZ)
AA Range: 5 -6%
Characteristics: Orange marmalade flavor, with some citrus and floral character as well.
Substitutes: Possibly a combination of Mittlefruh and Amarillo.
Pacific Jade (NZ)
AA Range: 12 - 14%
Characteristics: Soft bitterness. Bold aroma of citrus and crushed black pepper.
Substitutes: Magnum
Palisade (US)
AA Range: 5.5 - 9.5%
Characteristics: Fruity but non-citrusy aroma; earthy undertones.
Substitutes: Willamette
Perle (GER)
AA Range: 6 - 8%
Characteristics: Spicy, minty aroma of moderate intensity and balanced bittering.
Substitutes: Northern Brewer, Northdown
Phoenix (UK)
AA Range: 7 - 11%
Characteristics: Spicy "English Ale" aroma with clean bittering.
Substitutes: Challenger, Northern Brewer
Pilgrim (UK)
AA Range: 9 - 13%
Characteristics: Spicy earthy character.
Substitutes: Target
Pioneer (UK)
AA Range: 8 - 10%
Characteristics: Citrus (less aggressive than American hops; more "English")
Substitutes: EKG
Polaris (GER)
AA Range: 19 - 23%
Characteristics: Minty.
Substitutes: N/A
Premiant (Czech Republic)
AA Range: 7 - 10%
Characteristics: Mild, pleasant aroma.
Substitutes: Styrian Goldings, perhaps Saaz and Aurora
Pride of Ringwood (AUS)
AA Range: 9 - 10.5%
Beta: 5.5 - 6%
Cohumulone: 32%
Characteristics: Unique, intense aroma describe as "coarse," citrusy, herbal. Ubiquitous Australian hop.
Substitutes: Cluster, Galena
Progress (UK)
AA Range: 5 - 7%
Characteristics: Mildly spicy or woody, hint of juniper, similar to Fuggle but slightly sweeter.
Substitutes: Fuggle
Rakau (NZ)
AA Range: 9 - 11%
Beta: 4.6%
Cohumulone: 25%
Characteristics: Grassy and spicy upfront, with some peach and tangerine in the finish. Click through for notes on my Rakau single hop pale ale.
Substitutes: N/A
Riwaka (NZ)
AA Range: 5 - 7%
Characteristics: Strong grapefruit citrus character.
Substitutes: Cascade
Saaz (Czech Republic)
AA Range: 3 - 5%
Characteristics: Soft aroma and bitterness, maybe the quintessential "spicy" hop. Noble hop traditionally used for pilsners.
Substitutes: Sterling, Spalt
San Juan Ruby Red (US)
AA Range: 7%
Characteristics: Wild growing hop discovered in CO. Fruity, slightly sweet.
Substitutes: n/a
Santiam (US)
AA Range: 5 - 7%
Characteristics: Similar to Tettnanger. Herbal, floral.
Substitutes: Tettnanger
Saphir (GER)
AA Range: 3 - 5.5%
Characteristics: Sweet, clean, spicy; citrusy with an almost tangerine aroma.
Substitutes: Hallertau
Satus (US)
AA Range: 12.5 - 14.0%
Characteristics: Similar to Galena.
Substitutes: Galena
Select (GER)
AA Range: 4 - 6%
Characteristics: Bred to be similar to Spalt, Tettnang, Saaz.
Substitutes: Spalt, Tettnang, Saaz
Serebrianka (Russia)
AA Range: 3.5%
Characteristics: Light perfume aroma.
Simcoe (US)
AA Range: 11 - 14%
Beta: 4 - 5%
Cohumulone: 15 - 20%
Characteristics: Pine and citrus, sweet berries and perfume. Unique, complex flavor with very smooth bittering. Click for notes on my Simcoe single hop pale ale.
Substitutes: A combination of Columbus and Centennial might come close.
Smaragd (GER)
AA Range: 4 - 6%
Characteristics: A new European response to Amarillo. Fruity nose, flowery; more prominent aroma than most European varieties; balanced subdued fruitiness.
Substitutes: Try a combo of German and American hops
Sonnet Golding (US)
AA Range: 6.6%
Characteristics: Similar characteristics to Golding hops.
Sorachi Ace (Japan)
AA Range: 12 - 16%
Characteristics: Lemony, Lemongrass, lemon-cream flavor.
Substitutes: Southern Cross
Southern Cross (NZ)
AA Range: 11 - 14%
Characteristics: Lemon, lime, pine.
Substitutes: Sorachi Ace
Sovereign (UK)
AA Range: 4 - 7%
Characteristics: Earthy, nutty, pine.
Substitutes: Fuggle
Spalt (GER)
AA Range: 3.5 - 5%
Characteristics: Spicy, Noble hop aroma.
Substitutes: Saaz, Tettnang
Stella (AUS)
AA Range: 14 - 16%
Beta: 4 - 4.5%
Cohumulone: 36%
Characteristics: Spicy, earthy, hints of star anise. Floral.
Substitutes: Mix of English and Noble varieties
Sterling (US)
AA Range: 5 - 9%
Characteristics: Floral, spicy, slight citrus aroma.
Substitutes: Saaz
Sticklebract (NZ)
AA Range: 11 - 14%
Characteristics: Piney, citrus. Harsher bittering.
Strisselspalt (France)
AA Range: 3 - 5%
Characteristics: Mild Noble-like flavor, spicy, herbal.
Substitutes: Hersbrucker, Hallertau
Styrian Goldings (Slovenia)
AA Range: 4.5 - 6%
Characteristics: Mild, spicy aroma.
Substitutes: Aurora, Fuggle, Williamette
Summer (AUS)
AA Range: 4 - 7%
Beta: 4.8 - 6.1%
Cohumulone: 23 - 25%
Characteristics: Apricot, orange marmalade, melon notes; undercurrent of mild earth, spice. Click through for notes on my Summer hopped pale ale.
Substitutes: Possibly Rakau, Amarillo
Summit (US)
AA Range: 17 - 19%
Characteristics: Smooth bittering with orange, tangerine, citrus character.
Substitutes: Apollo
Super Pride (AUS)
AA Range: 9 - 10.5%
Beta: 5.5 - 6%
Cohumulone: 32%
Characteristics: Unique, intense aroma describe as "coarse," citrusy, herbal. Ubiquitous Australian hop.
Substitutes: Cluster, Galena
Sun (US)
AA Range: 12 - 16%
Super Alpha (NZ)
AA Range: 10 - 12%
Characteristics: Piney, grassy, lemongrass.
Substitutes: n/a
Target (UK)
AA Range: 8 - 13%
Characteristics: Herbal, earthy, grassy.
Substitutes: Admiral
(Hallertau) Taurus (GER)
AA Range: 12 - 17%
Characteristics: Noble, aromatic, zesty.
Substitutes: Horizon, Herkules, Magnum
Tettnang (UK)
AA Range: 3.5 - 5%
Characteristics: Herbal, slightly spicy, woody.
Substitutes: Saaz, Spalt, Ultra
Topaz (AUS)
AA Range: 15.5 - 18%
Beta: 6 - 7%
Cohumulone: 47 - 50%
Characteristics: Lychee fruit, tangerine, spice and resin. Touch of citrus.
Substitutes: Possibly Rakau, Stella
Tradition (GER)
AA Range: 5 - 7%
Characteristics: Sweetly flowery, earthy. Bred to be stronger version of Hallertau.
Substitutes: Hallertau, Liberty
Ultra (US)
AA Range: 4.5 - 5%
Characteristics: Spicy, floral, mild. Noble hop replacement.
Substitutes: Saaz, Spalt, Tettnang
Vanguard (US)
AA Range: 5 - 6%
Characteristics: Slightly flowery, herbal, and mild. Similar to Hallertau.
Substitutes: Hallertau, Spalt, Tettnang
Waimea (NZ)
AA Range: 15 - 16%
Characteristics: Pine needles, citrus fruit, grapefruit, tangerine.
Substitutes: N/A
Wakatu (NZ)
AA Range: 7 - 9%
Beta: 5.8% - 8.5%
Cohumulone: 28 - 35%
Characteristics: Mildly spicy, with a floral and citrus / lime character. Also known as Hallertau Aroma.
Substitutes: N/A
Warrior (US)
AA Range: 15 - 17%
Characteristics: Clean, mellow flavor; mild citrus lemon character.
Substitutes: Bravo, possibly Apollo or Magnum
Willamette (US)
AA Range: 4 - 6%
Beta: 3.5 - 4.5%
Cohumulone: 30 - 35%
Characteristics: Herbal, woody, earthy.
Substitutes: Fuggle, Tettnang
Zeus
See: Columbus/Tomahawk.
Zythos (US)
AA Range: 10 - 12%
Characteristics: Strongly aromatic, with tangerine, lemon, grapefruit, and pine notes.
Substitutes: Cascade, Ahtanum, Sorachi Ace
To compile these results, I basically Googled each hop and tried to cross-reference at least four or five different resources. (However, many newer hops only had one or two sites describing them, so I did the best I could.) Sites referenced include Northern Brewer, Rebel Brewer, Brew Dudes, Beer Advocate, Wikipedia, beerlegends.com, usahops.org and the HomeBrewTalk Wiki — all fantastic sites and resources. I also tried to avoid hops