Chickens on pasture are great: lots of sunshine and bugs for the hens, they deposit their manure on the pasture, and it couldn’t be a starker contrast than their industrial counterparts that live in dark, smelly, and noisy indoor facilities. However, one side effect from grazing laying hens on pasture are the bare patches where the chickens take their afternoon dirt baths. These bare patches are invitations for weeds, so we re-seed them. However, in some cases we’re left with a mix of grass and clover species we want, along with some weeds that we don’t want. For instance, the photo above shows dock, which is a typical weed we see in our pastures following grazing with chickens.
While dock is a nutritious plant, it is not as palatable as our typical forage grasses. In a situation where cows are set-stocked, or left in one large spot for a long period of time, the cows will ignore the plant while it takes over much of the pasture. We manage dock by increasing the stocking density of our beef herd. Increase stocking densities of grazing cows is a practice many grazers practice with a goal of forcing cows to eat a broader range of available plants in a given area, along with directing the flow of nutrients from the cow itself: in short, we want to force them to eat the dock along with the good stuff. We found that at a stocking density of at least 80,000 lbs to the acre, the cows will strip the leaves off most of the dock plants. The photo below shows our cows in the pasture with most of the dock grazed down on the right (where they were the previous day) and the cows on the left (note the fiber-glass posts holding up our electric fence-line in the foreground).
The pasture shown in the photo is a dry-land pasture and was used to raise pullets (young laying hens) last summer and fall and consequently the grass was stressed on this paddock last season. The recovery this Spring was somewhat slower than other pastures so we were not able to feasibly put more than 80,000 lbs to the acre on this pasture. However, after the first grazing 10 days ago, the pasture is recovering nicely and already has re-built a nice stand of grass, ready for grazing in another 2 weeks.
I should note that we are an organic operation so our options for managing weeds are limited to what is in the organic toolkit. Dock is not the only weed we battle. The worst is canada thistle, and while i’ve seen intensive grazing slow its spread and discourage it, it is not enough to entirely manage it. Timed mowing (first week of July, or just at bud-break), annual rotations (e.g. Sudan timed to compete effectively), and when necessary hand-weeding are effective complements to high stocking densities.
A final note for this blog post is that we’ve been working with our interns on calculating stocking density and factoring in associated times, areas, and dry matter. A tool for working with stocking density and other grazing resources are available at our Intern resources pages.