It’s no secret deer consume a long list of plants. In fact, there have been hundreds of articles, research papers and even books written on the subject. Much of the analysis of a deer’s appetite has been focused on woody browse and hard mast, for good reason. These two items make up a large percentage of a whitetail’s diet. However, during the summer months forbs are often the bulk of their diet, a fact that is often overlooked by hunters. Deer eat dozens of different species of forbs, but I’ve chosen seven you should know that represent a variety of species and are highly nutritious.
What Are Forbs, Anyway?
A forb is simply an herbaceous flowering plant that is not a grass and typically does not have a woody stem. Wildflowers, weeds, and broadleaf plants are all terms that could be used synonymously with forb. Some forbs are annuals, meaning they grow from seed each year. Others are perennials that sprout from the roots. Regardless, forbs play an important role during the summer for white-tailed deer. This time period should be important to all of us deer enthusiasts, because does are lactating and raising fawns, and bucks are developing antlers.
Some forbs are superior in crude protein when compared to commercial feed supplements, making forbs a much cheaper, more natural and time-saving option as opposed to feeding deer all summer. These seven species develop at different times during the summer, thus providing forage all season long. They are all common across much of the whitetail’s range. Some are easily encouraged through various management techniques. A couple develop without intentional efforts, and one often must be planted under most circumstances. Let’s explore each species in detail.
Common Ragweed
A member of the aster family and the bane of many allergy sufferers, common ragweed is a prolific annual forb that likes disturbance. Common ragweed typically grows 3 feet tall, although it can reach taller heights in ideal growth conditions. It has one main stem with fern-like leaves containing many narrow lobes. It also happens to have crude protein levels near 18%, making common ragweed an ideal natural food source for deer.
Promoting common ragweed is quite simple, making it a top choice for habitat management efforts. Common ragweed prefers recently disturbed sites. Because it’s an annual plant, seeds lying in the soil are poised and ready for a disturbance to allow their release. Common ragweed often pops up in recently disked, burned or sprayed areas.
One of my favorite techniques is to burn grass-dominated areas in early spring, then spray with glyphosate after 4 to 6 inches of new growth has occurred. This commonly results in a significant flush of common ragweed, among other forbs. Another option is lightly discing grass-dominated areas or idle food plots in late winter or early spring to get the same result. Prescribed burning will also promote common ragweed, but not to the extent of using chemical or mechanical disturbances. Keep in mind, because common ragweed is an annual that emerges from seed each year, as years pass after the original disturbance, common ragweed’s presence will diminish as other plants take over. Frequent disturbance is necessary to maintain a significant stand of ragweed. As a side benefit, common ragweed also attracts lots of insects making it ideal for turkey and quail broods. It also produces a highly nutritious seed that many birds relish.
Giant Ragweed
Similar to its cousin above, giant ragweed also likes disturbance. However, the structure of giant ragweed is significantly different than common ragweed (see the photo above showing both species). Giant ragweed grows very tall and has large, shallow lobed leaves attached to a strong stem. Giant ragweed leaves are also high in crude protein, but its desirability seems to differ across the whitetail’s range. Some landowners commonly find giant ragweed browsed where other parts of the country see little use. It may not be a difference in the plant itself as much as a difference in other forage that is available. Perhaps in locations where giant ragweed seems to be largely ignored, other more palatable species are available that divert the deer’s attention? Regardless, in locations where giant ragweed is being browsed, it is nutritious and easy to promote.
Disturbance is the key. Giant ragweed, in my experience, will express itself in areas with slightly more moisture. Common ragweed seems to excel in very dry, poor soils but giant ragweed usually appears in better or wetter soils. Due to giant ragweed’s height at maturity, it can provide cover in addition to food. Deer may feel more at ease moving through a stand of giant ragweed during daylight simply due to the fact it stands taller than their body, making them feel concealed. Both varieties of ragweed emerge in early spring and grow all summer, providing a long window of foraging opportunity.
Pigweed
Don’t send me hate mail for this one! If you despise pigweed and battle it on your farm, I completely understand, and I don’t blame you for your stance against pigweed. But in some cases, pigweed can provide valuable additional forage. There are many species of pigweed, and most are very palatable to deer. However, with pigweed, things can become problematic in certain situations.
Pigweed is another annual, and like most annuals it produces a huge number of seeds. Pigweed tends to develop in food plots and other disturbed areas. Some species thrive in wet conditions, where others can handle drier environments. This isn’t a species I ever intentionally promote, but I don’t fear it’s presence either, as I know it provides quality forage on my farm. However, in portions of the country some pigweed species have become resistant to several herbicides, including glyphosate. Where this is an issue, or on farms that include production agriculture, allowing pigweed to persist may not be an option.
Finding pigweed in food plots is not ideal as this is where the herbicide resistance develops. This leads to another discussion, the importance of changing food plot species and techniques occasionally and not planting the same food plot to the same species year after year. Where pigweed can be allowed to grow, deer will consume the leaves, ingesting high levels of protein in addition to vitamins A and C as well as iron and other minerals. Upper edges of wet areas can develop some pigweed on occasion. Areas heavily trodden by cattle near a corral, feed bunk or pond edge can also produce some pigweed. It’s in these situations that I find pigweed a useful forage supplement.
Pokeweed
This is another species that I do not make a concerted effort to promote, but it shows up anyway after various habitat treatments or disturbances. Pokeweed has a ridiculous amount of crude protein, topping the charts at 32%. Pokeweed is perennial and grows quite large, sometimes exceeding 10 feet tall. It has large leaves and distinctive purple berries. Deer eat both the leaves and the berries, which ripen in late summer. As a side benefit, pokeweed berries are also consumed by a variety of birds and small mammals.
Pokeweed seems to show up quickly in newly established forest openings, also known as bedding thickets. Periodic fire does not discourage pokeweed but instead helps keep these areas open longer, allowing pokeweed to continue to persist due to extra sunlight.
Pokeweed also seems to flourish in areas where fire burned extremely hot. Open field or edge sites where a brush pile or downed tree gets completely consumed during a burn operation will often yield pokeweed during the next few years. These areas are often considered “sterilized” from burning so hot, and as such, some land managers attempt to avoid such a buildup of fuel loading by spending time to scatter woody debris. However, pokeweed seems to be able to withstand the poor growing conditions of supposed “sterilized” spots and take advantage of the opportunity where few other plants can grow. As a consultant, I often encourage landowners to dismiss the concern of hot spots and welcome the opportunity to produce some pokeweed. This not only produces a preferred food source but also saves time for other management activities.
Partridge Pea
This annual legume has protein levels near 30%. It grows readily in grasslands and old field habitats and is common along roadsides and waste areas. It is related to mimosa and its leaves look very similar to those of a mimosa tree – except partridge pea is native to North America.
Partridge pea is a prime example of a forb that is primarily consumed during a certain growth period. I remember regularly checking on partridge pea plants during their first growing season in a 10-acre wildflower planting I installed several years ago. I was disappointed during each check in May and June. The deer had not eaten any of the several hundred plants scattered throughout the planting. Finally, during a late July check I found nearly every partridge pea browsed down to half their size from my previous inspection. The plants had clearly reached a palatable stage of growth that the deer found irresistible. Literally every pea plant in the entire 10 acres had been browsed.
In places partridge pea is already present, prescribed fire can help encourage its persistence. Burning in fall or winter will help suppress grass growth and encourage more forbs like partridge pea. Light discing in grass-heavy areas can also release partridge pea. However, some locations will be void of any partridge pea seed stock in the soil. If this is the case, there is an easy fix: direct seeding. Partridge pea is a very affordable and easily established forb. It can be drilled or broadcast in a new planting or added to an existing planting. If you intend to broadcast, burn the site in late fall or early winter, then broadcast the seed mid-winter. The subsequent freezing and thawing of the ground will help move the seed into the soil, thus sprouting the following spring. As with many legumes, partridge pea is also beneficial to a wide array of birds and other wildlife.
Illinois Bundleflower
The fern-like leaves of this perennial legume make this species easy to identify. Also related to mimosa, the protein level in bundleflower tops out around bloom time in July at 18%, making this another fantastic forb. Deer will consume the foliage throughout the summer. Illinois bundleflower thrives in areas receiving sunlight throughout the day. Grasslands, old fields, and roadsides are all likely locations for bundleflower.
Since Illinois bundleflower is a perennial, it is not as reliant on disturbance to persist. However, rank grass can often suppress the ability for bundleflower to compete. Maintaining a prescribed burn rotation or other grass suppression efforts like light discing or strip spraying can help maintain the presence of Illinois bundleflower for several years. Additionally, much like partridge pea, bundleflower is easily established by direct seeding. Drilling or broadcasting as described above will yield good results. I almost always recommend both partridge pea and Illinois bundleflower in plantings, due to the ease of establishment, the reasonable seed cost, and the huge benefits to a variety of wildlife species. Legume seeds are incredibly nutritious. This provides great benefits beyond just deer forage for the summer. Quail, turkeys, and many songbirds relish legume seeds in the fall.
New England Aster
This one is admittedly a bit obscure. There are several species of aster, and many are not palatable to deer. Old field aster is an exception and is a fairly common plant across the whitetail’s range. However, I selected New England aster for this seventh spot due to the timing of both its bloom and forage preference. This perennial doesn’t bloom until September in much of its range, which is also when deer decide it is worth eating, preferring to eat the actual blooms themselves. It has a beautiful purple flower, making it a great addition to any pollinator planting. This species is relegated to higher quality grasslands, savannas or open woodlands, but it tolerates a wide range of soil conditions.
New England aster isn’t commonly found in old fields or sites that have experienced some historical abuse. If you haven’t seen it on your hunting land in the past, then conducting some sort of disturbance will not likely result in this species magically appearing. However, adding this species to an existing planting or a new forb planting is a great way to establish it where you hunt. Keep in mind, depending on the other plants or mast available in your area in September, this species may not see the use by deer that occurs in other parts of the country. If you consistently have acorns hitting the ground by mid-September, or a nearby alfalfa field exists, New England aster may not be the first thing on a deer’s mind. Regardless, the late bloom timing makes this species a huge benefit to late-season pollinators as well.
The List Goes On
Take the time this summer to learn whether any of these seven plants exist on your farm. Remember that palatability can vary based on the growth stage, so inspect them each month and see what kind of browse pressure they are receiving. These species are just a drop in the bucket of forbs that deer will consume. Don’t stop with these seven species, but learn and evaluate other species deer are consuming where you hunt. Take notes on any species that seem to be highly preferred, then take the time to research techniques to increase those preferred species. Doing so will not only increase the deer forage but will likely benefit a wide range of birds, insects and other wildlife.