Lessons from Drought Tolerant Weeds

Christine Gelley, Agriculture and Natural Resources Educator, Noble County, OSU Extension

Because it’s deep rooted, wild carrot thrives in dry weather.

The Ohio State University’s State Climatologist, Aaron Wilson, has told me before- “The best way to end a drought is to talk about drought.”

I am hoping he is right. Maybe by the time you read this article we will have had some substantial rainfall. But as I write this in late August, my area of Ohio continues to suffer from the impacts of the summer drought. It is difficult to find inspiration for hope when the factors that cause this struggle feel beyond our control. However, the optimist in me is always looking for the bright side of any situation.

Beef Cattle Field Specialist, Garth Ruff, recently offered some inspirational points of view in an article looking back on a road trip through Texas that can remind us how blessed we are in Ohio to have ample rainfall in our normal growing seasons. Many cattle operations there create their annual management plans relying on half the rainfall we receive in a normal Ohio year. While they may be more conditioned to droughty conditions, how to stock cattle on dry ground, and how to offer supplemental feed to make up the difference, it is not out of reach for Ohioans to borrow tips from cattle producers in more arid climates to help cope with our abnormal year.

You can read more about tips for managing the herd during drought on the OSU Beef Team webpage: https://beef.osu.edu.

When I look around for inspiration, I look at what plants are still green and growing. At this point, there isn’t much to speak of in the category of “desirable forage”. But there is green growth out there and that growth is from weeds. Some of the most prevalent plants that I see continuing to growth through these harsh conditions are chicory, Queen Anne’s lace, joepyeweed, ironweed, and golden rod.

What is special about these plants that they are thriving, while our other grasses and legumes are dormant?

These plants are adapted for survival of the harsh conditions.

Chicory and Queen Anne’s lace have taproots that allow them to reach deeper into the soil to access water and nutrients and that taproot serves as a structure to pack them away and draw from later. Joepyeweed, ironweed, and golden rod are all perennial weeds in the aster family that have strong extensive root systems. These expansive root systems aid in providing access to water and nutrients while providing the storage to draw from during times of stress. We are in a distinct time of stress. Even these drought tolerant plants are wilting in the extreme heat, with little moisture left to draw from the root system.

One stress factor that is reduced for these weeds is livestock grazing. While deer do browse them, sheep and goats may as well, cattle prefer other options. Our desirable cool-season grasses and legumes have been chronically stressed for months and most have been grazed to the ground. What little leaf tissue that remains is brown and brittle. It will take rain, time, and rest for them to recuperate and be productive again.

Even those forages with expansive root systems will struggle to recover from summer grazing without relief from drought. Earlier in the summer it seemed that warm-season perennial grasses may have benefited from the hot and dry conditions. With the ability to reach deep in the soil profile and a different pathway of photosynthesis, those warm-season perennials can withstand drought stress longer than cool-season forages. The intense conditions suppressed competition from other plants in the ecosystem. But the extended period of time with no rainfall made regrowth after grazing or haymaking very slow. By the end of September, their season of active growth comes to an end. Without rain, they may not be able to be used again in 2024.

It wasn’t until a sprinkle of rain hit our area in early August that we even saw the foxtails, crabgrass, barnyard grass, and goosegrass germinate. Normally those grasses are prevalent by mid-July. But without moisture for seed to germinate, the seed laid in wait on an empty spot of exposed soil waiting for a drink. At this point, those annual weeds maybe be the only green grass left for cattle to eat.

The lesson I am choosing to see from the profile of what plants are green and growing is that the secret formula to drought tolerance and resiliency is to:

  1. Choose a diverse offering of forages that include annuals, perennials, cool-seasons, and warm-seasons, grasses, legumes, and forbs.
  2. Be sure to include plants that have the ability to store away resources for a time of need.
  3. Allow forages the space and time to rest between grazing events and designate areas that can be used as sacrifice feeding areas when grazing opportunities become limited.

Nothing lasts forever. This drought won’t either. We can make it through and we will experience better seasons ahead.

Producers who have been impacted by intense drought in 2024 are encouraged to visit the Farm Service Agency website at https://www.farmers.gov/protection-recovery/disaster-tool to explore what relief options may be available and how to apply for them. Also visit our OSU drought response website at: https://kx.osu.edu/page/early-drought-response for helpful tools from OSU Extension.