Habitat & Conservation  |  09/28/2018

Ragweed: The Irritating Miracle Plant


Ragweed serves as prime year-round habitat for gamebirds

By Jim Wooley, Pheasants Forever senior wildlife biologist (emeritus)

Sniffly hunters with allergy problems may want to stop reading now. 

We are about to confront the dilemma that ragweed poses for many of us. Ragweed pollen is a potent allergen, causing millions to dread late summer and early fall flowering. 

But ragweed ranks among the best plants of all for wildlife. You want it on your land. All year long.

Most folks are familiar with the knee-to-waist-high common variety, unaware there are 18 North American native ragweed species in all. Most ragweeds are annuals belonging to the composite family of wildlife friendly plants including asters and sunflowers.  

Here’s the not-so-nice news for hunters with allergies: A single common ragweed plant can produce up to one billion pollen grains that fly on the wind-for hundreds of miles. Interestingly, increasing temperatures have boosted ragweed pollen production in recent decades, a little bonus for allergic climate change doubters.  

But there is a silver (or perhaps even gold) lining. All that human suffering has a wildlife payoff.  

Common ragweed produces abundant seed, exceptionally rich in crude fat and protein. That seed is retained on plants well into winter, so it’s available to foraging wildlife. Ragweed ranks among the best and most preferred natural quail foods. Pheasants eat it. And it provides sustenance for a legion of wintering songbirds.

Ragweed greens are preferred summer deer browse. And giant ragweed, which often grows over 10 feet tall, has the right structure to provide fall and winter loafing areas for both pheasants and quail.

Importantly, ragweed serves as prime summer habitat for gamebirds. Broods need early successional plant communities, not thick grasses choked with litter. Ragweed fits that bill nicely for pheasants, quail and turkeys. The low stem density allows easy movement so that hungry chicks can find ample bugs in the soft vegetation. And there’s canopy overhead for concealment from avian predators. 
Getting this miracle plant is relatively simple. While you can buy common ragweed seed somewhat inexpensively, it’s most likely been planted for you already at no cost. The seed is widely dispersed by wildlife and weather, persisting in the soil for up to 80 years. To activate, alter the existing plant community — ragweed likes disturbance. Just stir the soil with disking, graze heavily, burn in fall or early winter, or apply chemicals at strategic times.  

When disking you have options.  Spring and early summer disking creates ragweed this year, while fall disking prepares for next year’s brood cover (you’ll also likely get pigweed, lambsquarter and other wildlife plants).  Ragweed usually dominates a heavily disked area for just one season. The next year, it reverts to higher levels of biennials, perennial forbs and grasses. To keep succession at bay, heavy disking applied every other year or on a 3-year rotation allows ragweed to surge again. 

Mid- to late-fall is prime time to stimulate the next season’s ragweed production with prescribed fire. Strip disking in combination with prescribed fire is also very helpful where grasses are well established.  Spring burns timed for maximum damage to cool-season grasses may have remarkable success stimulating giant ragweed. Fire can be hard to handle; be well planned and staffed before you light the match.

Finally, herbicides such as glyphosate can kill back competitive grasses and allow annuals like ragweed to thrive. Autumn, when other vegetation has gone dormant, is a great time to set back grasses like brome and fescue that are actively growing, and pave the way for abundant ragweed next year. 

Saying "ahhh-chooo" may mean you have some prime wildlife habitat on your land.