The hair of the deer family (Cervidae) and the rest of the Artiodactyla (even toed ungulates) are up there with chickens for providing the most versatile of fly tying materials. Not that you may care that much but a bit of taxonomy...cervids include deer, moose, elk, and caribou. They are part of the order Artiodactyla, the "even toed ungulates", include a wide variety of animals from whales (I shit you not!), giraffes, pigs, cows, camels, hippos, llamas and alpacas, sheep and goats, antelope, deer, and Pronghorn. It's a diverse group - about 270 species of artiodactls of which about 55 are cervids. Obviously, this group ranges widely, particularly the Cetaceans (whales, dolphins) which account for about 90 species and cover most of the "Blue Planet".
Most classically, the applications of cervid hair are tails, bodies (spun/stacked bodies, humpies), wings (compara/sparkle duns, caddis, stimulators, etc.), and a number of streamer components. With this wide range of applications - and I've not covered them all - knowing what hair is right for your application requires some experience. There is a huge amount of variability in the properties of deer hair. Hell, it's even used for dubbing...
Typically, at least in North America, "deer" tends to refer to White-tailed Deer (Odocoileus virginianus). Even within the White-tailed deer, there is considerable geographic variability in the hair. Much of what gives deer hair the characteristics that in-turn tell us about their utilization by fly tyers, is how hollow the hair is and where in the hair fibers the hair is hollow. To be a bit more precise, deer hair is never "hollow" as in the sense that a straw is hollow. Rather it is honeycombed with air chambers that help insulate the deer. Thus, late season deer hair will be more hollow (sorry, I am going to continue to use hollow, it's simply easier) than will be earlier season hair.
In simplest terms, hair that is hollow along most of the hair is for spinning or stacking. The least hollow hair is used for tails, upright wings, and down wings. You may see deer hair labeled with qualifiers such as Texas (less hollow; tails and upright wings like in Wulff style flies), Coastal (low-intermediate hollowness; compara-wings), Northern (more hollow; various applications - depends upon the location on the hide), and early season (less hollow) and late season (more hollow). Additionally age matters with older deer being particularly good for larger spun or stacked hair bodies or heads. Younger hair is generally better suited for Comparadun and caddis wings. These are all general approximations and where on the hide the hair comes is generally more important than any of these factors.
The images above show two pieces of White-tailed Deer hair that are suited for two really different purposes. The hair on the left is Blue Ribbon Flies Sparkle Dun hair used to tie the spread, upright wings of comparaduns and sparkle duns. To the right, is their X-caddis hair which you will note is "crinklier" which indicates more hollow air pockets in the hair which is suited for the slightly flared down-wing caddis imitations. Quite simply, Blue Ribbon Flies have the best hair I've seen these two applications. The great thing about buying deer hair today is that there are a number of retailers and wholesalers that have done an excellent job of taking the guesswork out of it for the tyer.
To keep things simple and the post a little shorter, I will cover the most typical applications of White-tailed Deer hair and a bit about the other species of Artiodactyla that tyers are likely to use.
Types of Hairs and Applications
Spinning and Stacking for Bodies and Heads
I would consider myself to be a pretty good tyer - I've been at it for about 30 years after all - and I'm sure I've tied a few thousand dozen flies over that time. I am not great with spinning, stacking, or particularly in trimming deer hair bodies and heads, but I'm getting better.
For spinning and stacking, you are looking for a patch of hair that has the tips intact and is hollow fairly well into the tips. You will find different hair fiber lengths which will range up to about two and a half inches in length. What you will want will vary based on your application - smaller flies require shorter hairs. Generally spinning and stacking hair comes from two locations on the deer, the white belly hair and the rump and body hair. Belly hair being white takes dye much better and will be more vibrant. Rump and body hair will be mottled and not as vibrant but it tends to be straighter and have stronger tips making it ideal for collars as well as spun/stacked bodies or heads. Use belly hair when you want clear breaks between colors - like a head that is white underneath and darker above.
Pronghorn (Antilocapra americana) are not a member of the antelope family despite many referring to them as "Pronghorn Antelope" , instead they are in Bovidae (cow family). Pronghorn are the only extant (still living) species of what was once a more diverse family (Antilocapridae) native to North America. As with many other large mammals, several antilocaprids are generally thought have gone extinct not long after humans arrived in North America. Pronghorn hair tips are often broken and the hair is thought to be quite brittle by many tiers. I have a piece or two of it but find little reason to use it. Maybe if I could find better pieces. It is certainly one you want to have in hand to buy or you are pretty likely to get a patch with a lot of broken tips. Their hair is quite hollow so it is mostly suited for spun and stacked bodies.
Caribou (Reindeer; (Rangifer tarandus) hair is short, very hollow, and fairly brittle. It is most typically used for smaller spun bodies like on the Irresistible or Goddard Caddis (though deer hair is what is typically called for in the patterns) and for wings on some caddis patterns. I have seen some refer to it as "CDC Hair" with the idea being it is a very light and "fluffy".
Hair for Wings
This is a pretty diverse category but I will cover four basic wing types based on what they aim to imitate and/or how they are tied. These four types are: upright wings such as in Wulff and Humpy patterns, flared down wings for caddis, upright (slightly) flared wings for compara- and sparkle duns, and larger down wings for grasshopper and stonefly imitations. Hairs suited for these applications vary based on hollowness, fiber length, and where these two factors intersect.
More hair from Blue Ribbon Flies (what can I say, I'm a fan of their deer hair) for humpies and stimulators. The hair for humpies is less hollow which is indicated by where the fibers become lighter in color and more "crinkly". The stimulator hair is a lot like really long X-caddis hair. That is, the tips are less hollow for longer but then the hair is relatively hollow from the base to the half-way point of the fibers. This would also make good hair for wings on grasshopper patterns, Madam-X, and other similarly large flies.
For sparkle duns and comparaduns, there are a number of options but my favorite has long been the stuff from Blue Ribbon Flies (yeah, I know it is starting to read like an infomercial). I have a number of different pieces of BRF Comparadun hair in a variety of sizes and colors. In the slideshow above, the first two are a piece for tying small (primarily #18 and smaller) sparkle duns and the last image, the piece to the left is for #12-16 flies (the piece to the right is their X-caddis hair).
A little secret, I tie most of the elk hair caddis with deer hair. Many tyers do. It is not that I do not use elk hair but my best pieces of hair for the sizes of caddis I normally tie are Blue Ribbon Flies X-caddis hair. For caddis in my typical sizes, primarily #14-18, I want a hair that begins to "crinkle" at about the place where I will be tying it in. Hans Weilenmann's CDC and Elk is without question the fly I have tied and fished more than any other pattern. Find a good patch of hair (I'd try Blue Ribbon Flies...) and you will have 100's of flies worth of hair. Buy a few patches - after all, when it comes to tying materials, it is pretty inexpensive. Better yet, call or include in your order you would like X-caddis hair for what particular sizes and they will pick a piece of hair that will suit your needs.
For larger flies like stimulators, elk hair may be better than deer hair.
Hair for Tails
Finding hair for tailing is probably more difficult than finding it for any other application. Quite simply, there is not a lot of hair on deer and elk hides that is non-hollow and well suited for tails. If you need this sort of hair, for say, the Close Carpet Fly or Cap's Hair-wing (Adams Hair-wing), you will be looking for Texas whitetail or similarly labeled warm weather deer hair. Additionally, you will find less hollow hair in legs and maybe along the spine to be less hollow. It is difficult to find good White-tailed Deer for tails. Blue Ribbon Flies humpy hair is reasonable for this application. A better hair for tails is often the hocks taken from Elk legs.
Moose hair (Alces alces) is typically used for a couple of purposes. It is a common tailing material for dry flies and nymphs and it is sometimes used like a quill body in flies like mosquito patterns. Reinforce the body with a little super glue or UV resin as the hairs are relatively brittle.
I will not give bucktail much time in this post as I have covered that ground in Project Clouser: Materials and other posts. Bucktails are used for all types of streamer applications and I'll cover some of these techniques down the road since I like to keep the reading time of each post at 8 minutes or less.
Summary
The hair of deer and other related species is a versatile and inexpensive fly tying material use for all types of flies. Hair from different species, individuals harvested at different times of the year, and from different part of their hide will have vastly different qualities. This is, in no small part why finding hair labeled for particular purposes can save you time and hassle. There are a number of others that have covered the topic in at least as much detail.
For more information:
Global Fly Fishers - Selecting Deer Hair and Buying Deer Hair
Kelly Galloup - Selecting the Right Deer and Elk Hair (video)