Dr. Matt Poore, Extension specialist, North Carolina State University, and director of Amazing Grazing, shared tips for evaluating and renovating pastures.
Poore said the question of whether or not to renovate a pasture comes down to two issues: changing the forage crop to a more productive crop or upgrading old pastures that have a low level of desirable forages or other problems.
“One example is converting toxic tall fescue to novel endophyte tall fescue, or maybe you want to add more native warm season grasses to your system,” said Poore. “The second reason is that you have old pastures that need help.”
But Poore said the real question is “Why does the pasture need renovation?” “Older pastures, if they’ve been well cared for and managed, can be very productive,” he said. “Maybe it’s management that led you to the situation.”
After determining that renovation is the answer, farmers must be willing to commit to the project and future management. “If you planted novel endophyte-free fescue 10 years ago and didn’t manage it well and the stand is thinning,” he said, “it doesn’t make sense to renovate it back to the same grass if you aren’t going to change management.”
Poore said the NRCS Pasture Condition Scoring System, which can be downloaded, is a great way to keep track of improvements made in the pasture over time. “If you’re new or becoming aware of the need to improve your farm, a good pasture scoring on all pastures will help you track that,” he said. “The total score gives you a guideline for management decisions and specific scores on different factors help focus your efforts in areas you can improve.”
Factors that influence pasture condition score include percentage of desirable plants, percentage legumes, percentage live cover and plant diversity and vigor. “Is there a healthy level of dead tissue residue for organisms to use?” he said. “Is it over- or under-grazed? And are livestock concentration areas taken care of properly?”
Soil features such as degree of compaction, presence of healthy roots, color and evidence of biological activity are also scored. “We’re going looking for erosion,” said Poore. “Evidence of sheet and rill erosion, wind erosion, stability of stream banks and the presence of gullies.”
There are a variety of methods to determine the percentage of certain plants present in a pasture. One of the easiest is a step point system, which involves someone walking randomly through the pasture, noting the species present at the tip of the walker’s boot. Poore recommends noting plants at 100 to 300 locations throughout the pasture.
“The step point method is simple to understand and do,” said Poore – no equipment is needed. “It’s a great educational tool. We can all learn from walking across pastures and identifying plants.”
The data are easy to summarize, and they provide information about all the plants in the field and not just the major species. The evaluator can make other notes about pasture condition indicators such as erosion as they cover the entire pasture and make observations.
“A step point determination begins with a preliminary assessment,” said Poore. “Carry a clipboard to write data on and bring two pens. Mark the tip of the boot, walk the field and stop every 10 to 30 steps, depending on pasture size, and identify the plant (or bare ground) the mark is touching.”
He suggested marking several hundred points throughout the pasture. “Be observant … and look for out-of-season weeds,” he said. “Are there little yellow tomatoes that indicate horse nettle?”
Poore noted that the evaluator must be able to identify plants accurately, which may be challenging in an overgrazed pasture.
“If you don’t know the [pasture] plants, start learning them,” said Poore. “Know the significant grasses, legumes and weeds.” For minor species, the important aspects are whether the plant is a grass or broadleaf, and whether it’s desirable or undesirable. Be able to identify any poisonous plants common in the region.
Poore said if farmers value species diversity, they will have to tolerate higher levels of weed species. Forage stands high in legume content will have more weeds.
“Good forages are the best weed control,” he said. “Forage management will help keep it that way. Are the weeds toxic, and what is the economic threshold?”
Highly toxic species such as poison hemlock and wild cherry can kill animals. Less toxic weeds include hemp dogbane, horse nettle and buttercup. “We can live with some that are not as poisonous, but we have to take action with weeds that are more poisonous,” he said.
Something to keep in mind is when animals are grazed tightly in pastures with potentially hazardous species, they’ll tend to eat more than if they’re allowed more space.
Indicator plants can help the grazier discover problems. “Dutch-stye white clover that’s three or four inches tall at most, annual bluegrass, chickweed and buttercup are indications of overgrazing,” said Poore. “Other species like horse nettle, annual bluegrass, quackgrass, goosegrass and knotweed indicate compaction.”
Farmers can choose to do partial or total renovation, depending on the problem. If the pasture walk reveals mostly desirable plants, a partial renovation may be appropriate. “Look at fertility,” said Poore. “Soil test and understand the weeds. Herbicides can help with a weed problem. We may put out supplemental seed through frost seeding or overdrilling. We also want to rest it and relieve grazing pressure for a while so pasture can recover. Be sure the stocking rate is appropriate for the pasture.”
Total renovation is more involved and includes correcting soil fertility, tillage to correct rough spots, addressing grazing management issues and killing existing plants either with glyphosate or tillage. A summer smother crop can prevent emergence of undesirable seedlings. The last step is to reestablish desirable warm or cool season perennials to improve farm productivity.
Poore said there are costs and benefits in renovating toxic tall fescue pastures with novel tall fescue. “There are costs of spraying, planting the smother crop, planting the novel tall fescue and opportunity cost – lost forage production,” he said. “The benefits are improved weaning weights, improved breeding rates and reduced extra input costs incurred due to fescue.”
Eliminating a pasture for renovation or complete renewal requires graziers to consider forage options during the pasture’s down time. Poore advised farmers with newly acquired farms or acreage to renovate pastures prior to moving any livestock onto the property.
Other considerations during renovation include temporary reduction in livestock numbers, perhaps through contract grazing. Purchase hay or other feeds, use a smother crop to generate feed or increase production on other acreage by using more fertilizer and better forage management.
“All pasture renovation is costly,” said Poore. “If we do it right and relieve a toxic fescue problem, it can be good for the financial bottom line.”
by Sally Colby