Skip to main content

Which Minerals Do Deer Need?

We'll explain which supplements whitetails can obtain in the field, and the best ways to provide them with the ones they can't.

Over the years, I’ve written on a number of occasions about mineral supplementation for whitetails. That’s because it’s long been a topic of widespread interest — not only on the part of landowners and other habitat managers, but hunters, as well.

Despite the number of products now on the market and the amount of information published, many user questions continue. So here, during a time of year when mineral interest and use are high, I’d like to recap which minerals deer need and how to address those needs.

In the Beginning

Back in the early 1970s, two men came to visit me at the Institute for White-tailed Deer Management & Research in Texas. Larry Redmon and Richard Reed (the latter now deceased) were local cattlemen and avid deer hunters, and they had a question I’d never heard.

“We routinely give our cattle minerals,” Larry said, “and we wondered if it would be possible to make a mineral for deer?”

As I was at the time formulating a 20-year research plan for our institute, I decided it was a natural fit to include mineral supplementation in the plan. Interestingly enough, Larry later earned a doctoral degree in Range Management from Texas A&M University, and to this day he remains a recognized authority on range management and animal nutrition.

Believe it or not, in those early days little of the whitetail information we now commonly take for granted was known. Those actually were wonderful days to do research, as my colleagues and I “picked the low-hanging fruit” of knowledge.

In formulating a plan of attack regarding mineral nutrition, I went to the same folks we’d consulted about planting forages: dairymen. These folks should know more than anyone about proper nutrition for ruminants, a group that includes whitetails. Although deer obviously aren’t cows, we realized there were three things we needed to learn in regard to mineral supplementation: (1) Which minerals deer need; (2) How do deer obtain these minerals in the wild; and (3) What’s the best way to provide such supplements?

Which Minerals Really Matter

In reviewing the scientific literature, I quickly discovered there was very little known about critical minerals for deer. Most professionals relied on information generated primarily for small ruminants, including sheep and goats. Obvious dietary differences dictated that this information might only be elementary when it came to whitetails.

Minerals are important to all living things, serving a host of physiological functions. They’re classified as either macro- or micro-nutrients. These categories indicate the amount used by the animal. Important macro-nutrients include: calcium (Ca), phosphorus (P), potassium (K), magnesium (Mg), sodium (Na) and sulfur (S). Micro-nutrients include: iron (Fe), copper (Cu), Zinc (Zn), manganese (Mn), cobalt (Co), iodine (I) and selenium (Se).

While all these minerals are important, we quickly learned that Ca and P in particular had a lot to do with the size of deer and their antlers. A 1:1 or 2:1 Ca:P ratio is optimum. We also identified magnesium deficiencies in some Michigan deer when we discovered dozens of them eating mud rich in this mineral. As it turned out, the general area has long been known for a cattle disease called “grass tetany,” which is directly related to a lack of magnesium in the diet.

Micro-nutrients such as Cu, Zn and Se are particularly important to whitetails, responsible for many metabolic activities and immune development. In fact, there’s significant scientific evidence to suggest Cu deficiencies are linked to spontaneous occurrences of brain diseases such as “mad cow” and CWD. Compared to sheep and goats, whitetails are “copper hogs” that need a lot of the mineral.

Minerals in the Soil

As I detailed in the Spring issue, it’s safe to say that soils determine more about whitetail growth and productivity than any other factor. All soils are made up of minerals, and there are clear deficiencies in many areas. This particularly is true for sandy soils, as well as highly acidic (low pH) or basic (high pH) soils. When soil is either too low or high in pH, utilization of P is inhibited, greatly affecting body growth and antler production. Yes, whitetails will eat dirt, but the vast majority of minerals they consume enter the system through the plants they eat.


To be clear, most of the Ca and P used by a buck to grow antlers come from the flat bones of his body: where they were deposited the previous year. So mineral supplementation won’t show any antler effect for at least a year.

Interestingly, the immense prehistoric deer called the “Irish elk” (Megaloceros giganteus) went extinct during the last global warmup shortly after the Ice Age, apparently due to the loss of tundra plants high in Ca and P. Fossil evidence supports these deer were victims of spontaneous cervical fractures caused by osteoporosis.

Best Way to Provide Supplements

We’ve learned that a multi-pronged approach to providing deer minerals is best. The first step is have the soils analyzed for the critical macro- and micro-nutrients. This should be followed by developing a food-plot or native-plant fertilization program to ameliorate any deficiencies.

The author dispenses granular mineral into a covered trough. He much prefers this type of system over using blocks or pouring mineral onto the ground. (Photo by Haynes Shelton)

For example, in much of South Texas (which is broadly deficient in P), low rainfall makes trying to grow traditional food plots a “fool’s errand.” Instead, we apply 50 pounds per acre of triple-superphosphate (0-45-0) fertilizer to native brush. In so doing, we get fantastic response from the deer herd.

For most whitetail managers, one of the best ways to supplement mineral nutrition is (where legal) through supplemental feeding. A balanced pelleted ration can deliver all the mineral nutrition needed by the herd. However, in many areas feeding isn’t a legal option.

Deer aren’t cows; they don’t like to lick blocks the way their bovine cousins do. The best way to provide supplemental minerals is by using a granular mineral that contains less than 30 percent salt and has Ca and P at the rate of 12 percent each. Of course, the other macro- and micro-nutrients should be included in lesser amounts.

While it sounds simple to concoct your own mineral mix, that’s really not a good idea. I know of some deer managers in Ohio whose homemade mineral mixes gave the animals heavy metal poisoning! Leave formulation to the professionals.

In the old days, we simply dug holes and poured granular mineral into them. But we now know that was a really bad idea. By delivering mineral in this way, you’re exposing deer to greater risk of parasites and diseases.

A much better approach is to use a covered trough with a roof high enough for a buck to easily get his head inside (and be able to see all around as he does so). Inside the trough, place a metal or plastic pan to hold the mineral. Every two weeks, remove any remaining mineral and wash or wipe out the pan with 50 percent bleach water to kill bacteria and parasite eggs.

In Conclusion

As you seek to improve herd nutrition, there’s still no substitute for good native forage management. A solid habitat/nutrition plan should involve manipulating preferred plants to keep them within what we call the “deer zone” (within four feet of the ground), on a sustained basis.

However, soil limitations often dictate using supplements to fill in the blanks created by scarcity of critical minerals in the native environment. I believe that when properly provided, minerals can increase the productivity and quality of a deer herd.

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Recommended Articles

Recent Videos

For years, one of Publisher Laden Force's favorite hunting programs has been the Outdoor Channel's Live 2 Hunt program with Cody and Kelsy Robbins. Their passion for bowhunting and making new hunting buddies is contagious. Additionally, time and time again the pair has undoubtedly confirmed their position as some of the best deer hunters north of the Canadian border. So, Laden quickly accepted when an invite came from friend Mike Tussey of NOMAD Hunting Apparel to test new deer gear on a summer bear hunt with Cody and Kelsy's L2H Outfitting. Join him as he travels to north central Saskatchewan to put new NOMAD, the brand new Bowtech Carbon One and his sense of adventure to the test.
Destination Videos

Live 2 Bowhunt

Opening day is just around the corner, but there is still work to be done! The Forces complete the final prep steps, getting their hunting sites ready for easy access.

Opening Day Prep

The Forces complete the final investment, one that's not so “instant”, by planting new fruit/mast trees. 

Investing in the Future

Baseball transitions to football, which means it's time to get oats, clover & chicory in the ground.  

Cool Season Food Plot

Laden teaches the boys the importance of keeping your property clean to make final adjustments easier and less time consuming.

Property Management

The new hunting blinds have arrived, but the Forces get busy because the blinds aren't going to assemble and strategically place themselves.

Blind Placement Strategy

It's time for weed patrol! Laden ventures out to high cut the perineal plots, weedeat the electric fences and spot spray his clover. 

Plot Maintenance

Laden and the boys plan the off-season “to do's” and prep their equipment needed to execute each exercise. 

The Plan

Laden and his boys work through a timber management plan, letting Dad safely remove a few unwanted trees, opening up a canopy to help with understory native forage growth.

Timberstand Improvements

North American Whitetail Magazine Covers Print and Tablet Versions

GET THE MAGAZINE Subscribe & Save

Digital Now Included!


Give a Gift   |   Subscriber Services


Buy Digital Single Issues

Magazine App Logo

Don't miss an issue.
Buy single digital issue for your phone or tablet.

Buy Single Digital Issue on the North American Whitetail App

Other Magazines

See All Other Magazines

Special Interest Magazines

See All Special Interest Magazines

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Get the top North American Whitetail stories delivered right to your inbox.

Phone Icon

Get Digital Access.

All North American Whitetail subscribers now have digital access to their magazine content. This means you have the option to read your magazine on most popular phones and tablets.

To get started, click the link below to visit and learn how to access your digital magazine.

Get Digital Access

Not a Subscriber?
Subscribe Now

Enjoying What You're Reading?

Get a Full Year
of Guns & Ammo
& Digital Access.

Offer only for new subscribers.

Subscribe Now