I’ve looked at a few pastures this week that show signs of fertility and cultural issues. These are horse pastures which were planted in bermudagrass but have been overtaken by centipedegrass. This is very common in pastures that have not been limed over the years. Centipedegrass can withstand a lower pH than bermudagrass. Bermuda likes a pH no lower than 6.0.
I observed another pasture today where bermuda was established but now taken over by bahia and broadleaf weeds. Bahiagrass can also tolerate low pH and fertility. Horses also graze this pasture which results in soil compaction. In this pasture many broadleaf weeds have taken over like serrated ground cherry and chamberbitter. When much of the pasture is struggling to produce, it is recocomended to do a pasture renovation.
The first step in renovation is killing out the current grass species. This is better accomplished in the late summer/early fall with glyphosate. It can then be followed up by another spray, followed by planting a winter grass, like ryegrass. The next spring, that site needs to be cut or grazed real close and then sprig/seed your desired grass. UGA Extension Forage Agronomist Dr. Dennis Hancock has information on the UGA Forages website on specific grass species. (Click on Establishment Guidelines on the left and scroll down.) Here is what Dr. Hancock recommends:
“Renovating an old common bermudagrass stand is very difficult. Even with repeated glyphosate sprays, there will be some survival of old rhizomes. Some tillage in combination with glyphosate sprays with help expose rhizomes and increase percent control. Common bermudagrass can be more completely controlled if the land can be rotated for one to three years to crops where intensive grass control measures can be employed, in addition to using the glyphosate sprays.”