What is that in my lawn?
If you have a lawn or take care of lawns you probably have noticed a particular weed coming up recently. This is weed is a sedge (recognizable because it stems are angular instead of rounded) known as green kyllinga. According to The University of California IPM services, green kyllinga is a perennial plant that grows best in moist or wet areas that receive full sun, but it can survive some shade and drying once established. Green kyllinga grows well in warm weather from April through October. It is dormant in winter but remains green in warm climates where freezing doesn’t occur. It can yellow in the winter but doesn’t turn brown when it goes dormant. When left unmowed, green kyllinga can reach a height of about 15 inches but will adapt and grow in a prostrate manner if mowed. The plant produces a network of numerous underground stems (rhizomes) and can root and send out new leaves at each stem node. If green kyllinga rhizomes are removed and chopped into pieces, new plants can be produced from each node or stem section. Rhizomes in soil will begin to produce long, narrow leaves that are 1 to more than 5 inches long as temperatures rise in the spring. Chemical control of green kyllinga may be achieved with preemergent herbicides applied before the seeds germinate, with selective postemergent herbicides for established plants or with a combination of preemergent and postemergent herbicide treatments. The use of herbicides can be very effective if combined with cultural methods such as water management and exclusion of green kyllinga from turf and landscape areas.
Green kyllinga can be a major weed problem for turfgrass and landscape managers. In turf it forms a weak sod that gives poor footing for athletic fields and golf courses. Although green kyllinga is most often a problem in bermudagrass, it has been found in cool-season turf species as well. Green kyllinga has a texture and color that varies from normal turfgrass species and reduces the aesthetic quality of the turf. Also, green kyllinga grows faster than most turfgrass species, which gives infested turfgrass an undulating or irregular surface in as little as two days after mowing. Once a few plants become established in turfgrass or ornamental areas, spread can be rapid. In warm weather, rhizomes can grow by more than 1 inch per day, forming thick mats in just a few weeks. Mowing, foot traffic, and cultivation spread both seed and rhizomes. This allows the production of new plants and hastens spread.
The best management approach is to prevent new infestations by excluding and monitoring for the weed. Thoroughly clean mowers and cultivation equipment before moving from infested to weed-free areas. If solitary plants of green kyllinga are found, they should be grubbed out (i.e., remove the entire plant, roots and all) and the area monitored for several months to ensure removal was complete. When green kyllinga infests ornamental plantings, it forms a dense mat that crowds out desirable species and reduces the vigor of those plants that survive. Because of the extensive rhizome system in established stands, hand pulling or hoeing to remove green kyllinga usually is futile unless done repeatedly over a long period of time. Digging out plants and surrounding soil with a shovel is likely the best approach for removing rhizomes, although plant removal can be very expensive and not always successful. Once established green kyllinga will continue to spread unless control measures are taken.
Turfgrass and ornamental areas should be well maintained to promote maximum vigor and make these plantings as competitive as possible to hinder invasion by the weed. Dense turfgrass and ornamentals will shade the soil surface, making establishment of green kyllinga seedlings difficult. Irrigation systems should be adjusted and managed to eliminate wet conditions that favor green kyllinga.
Controlling green kyllinga in turfgrass requires a combination of control procedures. Wet or overwatered areas in turfgrass provide ideal habitat for a green kyllinga invasion. To reduce the chance of invasion or slow the invasion into turfgrass, don’t overwater the turf. If low areas stay wet, improve drainage or reduce water applications in that area. Early grubbing of solitary infestations has been successful when practiced diligently. Spot spraying isolated plants with glyphosate can be helpful, but the turfgrass also is killed, leaving open areas that allow reestablishment of kyllinga or invasion of other weed species. The open spots should be overseeded or patched with sod to establish a vigorous turf. Mowing and nitrogen fertilization also affect the growth of green kyllinga. In one study on hybrid bermudagrass, low mowing (i.e., 1 inch compared to 2 inches) resulted in increased green kyllinga seed germination and growth in established turf provided with adequate nitrogen. However, in newly established turf where there was significantly more green kyllinga present, the mowing height didn’t have as great an effect, and additions of nitrogen resulted in increased turf cover and less spread of green kyllinga. Unfortunately, eradication wasn’t possible with any mowing height or nitrogen rate.
- Cattlemen Classic and Ribeye Cook-off. October 6, 2017, downtown Sulphur Springs. A great opportunity to learn and enjoy the beef industry in Hopkins County. We will host a producer trade show with companies and support industry (starting at 2:00 PM) at the downtown area (free), a feature keynote speaker Trent Loos at the Courthouse (free) as part of the 2017 NETBIO producer meeting. The celebration continues with the cook-off competition, dinner (tickets available for $25 at Texas Heritage Bank and Brookshire’s in Sulphur Springs) and a free concert featuring Stoney Larue starting at 8:00 PM.
- Red Alliance Red Angus Production Sale. Registered Bulls, Females, and Commercial Red Angus. Oct 2, 2017 in the Hopkins County Civic Center. Sale starts 10 am / 150 head can be previewed on Sunday afternoon. Call John Macek @903-348-2138 for a catalog or www.redalliance.biz
- Private Applicators CEU and Hamburger Cook-Off. November 1, 2017. Join us to learn new techniques in weed management in pastures (1hr) hay production (1 hr), pond weed management (1 hr), Laws and Regulations related to use of restricted pesticides (1 hr), and protection of pollinators in agriculture (1 hr. IPM). Regional Civic Center. Call The Hopkins County Extension office at 903-885-3443 to register. Cost $30 lunch included.