The following is an update about the new Scott’s Bonus S Weed and Feed. As early as March, Tim Ray, Ron Strahan at LSU, and several other counterparts along the coast had shared their concerns that the metsulfuron containing product was causing injury to centipedegrass. Scott’s has officially recalled this product and will now replace it with the old formulation containing atrazine. Official website announcement.
For those of you who have followed the blog in 2014, you may have noticed a “Weed of the Week” series published throughout the semester. This is a direct result of the turf students enrolled in PSS 4823, Turfgrass Weed Management. During the semester, students were placed into groups and assigned a specific weed to discuss life cycles, identification characteristics, and control options. As you can all see for yourselves, the class did a great job discussing each weed that was highlighted. In addition, I partnered with Dr. Hock in the department of Human Sciences at Mississippi State University in order to collect data to monitor progress throughout the semester. We just received word that this blogging project was recently accepted and will be presented at the 2014 North American Colleges and Teachers of Agriculture (NACTA) conference. A job well done by our turf students! Student contributors included Dylan Boteler, Michael Denney, Dustin Miller, Douglas Martin, Jed McCoy, Ashley Averitt, Wes Dyer, Corey Garrison, Kyle Grider, Justin Hickman, Ethan Flournoy, Coleman Torgersen, Jordan Billingsley, and Christo Sullivan.
Below is the title and abstract that will be presented.
Blogging about Turfgrass Weeds: A Strategy to Improve Students’ Writing Skills in a Turf Weed Management Course
Blogging is a tool that is increasing in popularity among all ages and for many different uses. The use of blogging in the classroom is a unique tool to increase student comprehension and writing skills. Blogging in teams allows students to receive feedback from their peers to improve their writing. Students enrolled in Turf Weed Management at Mississippi State University were randomly assigned into groups of three to research, write, and publish a blog post on an assigned weed species. Students completed a brief questionnaire prior to working on the assignment to determine their familiarity with blogs. Of the 13 students in the class, 10 (77%) had never contributed to any blog. Following the initial blog posts, the instructor identified areas for improving the quality of content and writing ability. Spending more time initially helping students interpret appropriate information found on the Internet resulted in higher quality content in later posts. Also, going through line by line with students on each blog post has resulted in a more concise writing style. Students completed a questionnaire at the mid-point of the semester to assess how they were progressing with the assignment. Twelve students responded they were highly satisfied with the blogging portion of the course. The blogging component of the course has helped improve student writing skills and the ability to find reliable information about individual weed species.
Authors: Jed McCoy, Doug Martin, Jordan Billingsley
What is Carolina Geranium?
Carolina Geranium (Geranium carolinianum) is a member of the Geranium family (Geraniaceae). It is a native, broadleaf winter annual. One will typically find Carolina Geranium in poor soils and near dry areas; mainly landscape beds and thinner turf areas. This weed has been used medicinally as well. Mainly, it has been used to stop bleeding and sooth sore throats when crushed.
What does it look like?
Carolina Geranium is a diffusely branched weed standing about 1” tall. This geranium has long petiole stems that are often pink to reddish with hairy stems that flow into a finely divided palmate leaf. The flower also had a little inconspicuous pink bud. This weed is most commonly identified by its “stork’s-bill” seed head. It is a long, hairy, pointed head that will produce multiple seeds that contain hard seed coats.
How do I control it?
Carolina Geranium is a tough weed to control. Not only does the seed have a hard-coated membrane, which can withstand prolonged dormancy in the ground, but it also is hard to control with herbicides once established. Cultural practices include frequent mowing and hand pulling, while herbicide options include metsulfuron and trifloxysulfuron-sodium .
Authors: Michael Denney, Christo Sullivan, Dustin Miller
Shepherd’s-purse, Capsella bursa-pastoris, is a winter annual or biennial plant that reproduces by seed. Seed will typically germinate when soil temperatures are below 60oF in the fall or early spring.
Shepherd’s-purse first emerges in the form of a rosette. Base leaves are 3-6” long, about 1.5” wide, and deeply lobed. It is often confused with dandelion. The lower leaf surface has scattered hairs. The rosette overwinters, then resumes growth in the spring. A slender stalk appears and the plant continually bears flowers from spring well into the fall. The flower stalk may be simple or branched, and can grow 6 to 18” tall. The mature seed pods are found on the lower portion and clusters of new flowers can be observed at the tip. Individual flowers have four white petals that are less than ¼” in size. The leaves on the flower stalk grow 1-2” long and are shaped like arrowheads.
The flat seed pods are about ¼” long, with a notched tip and pointed base. A narrow stem about ½” long attaches each seed pod to the raceme. Seed pods are attached at a 90o angle every ¼ to ½” up the stem. The pods are initially green, then turn to a tan color with two rows of tiny yellow-orange seeds. Each plant produces roughly 30,000-50,000 seeds. Only 1/32” long, seeds are easily scattered by wind or water.
Mechanical – Tilling and mowing can be effective if done before flowering occurs.
Chemical – Mustards are resistant to many herbicides, but dicamba or metsulfuron can achieve good control.
Claytonia virginica L., otherwise known as Spring Beauty, is a part of the Purslane Family. This perennial herb is often considered a “sign of spring” because it is one of the earliest blooming spring flowers. The sweetly scented Spring Beauty overwinters and propagates through its corm (swollen underground plant stem that serves as a storage organ). Spring Beauty has made most of eastern North America its home. It has been located as far south as Texas, Louisiana, and Mississippi and as far north as Canada and Maine. Spring Beauty’s flower has five petals, five curved stamens, and three lobed stigmas, while the leaves are slender and lanceolate. The seeds are very small and are released when the capsule fruit breaks open. The seeds also have elaiosomes (fleshy structures on the seeds that are high in lipids and proteins) that allow for ant dispersal.
Spring Beauty has a very short life-span; therefore, instead of spending time and money to control it, one might choose to admire the beauty of the weed. Due to its low growing habit, mowing is usually not a viable option for control. Maintaining a strong turf canopy through proper turf cultural practices goes a long way in controlling this weed. For chemical control, broadleaf herbicides such as 2,4-D, mecoprop (MCPP), MCPA, dicamba, and tricolpyr are available. As always, read the herbicide labels and use the recommended rates.
Authors: Ashley Averitt, Wes Dyer, Coleman Torgersen
Hairy bittercress, Cardamine hirsute L., depending on its location, is a winter or summer annual weed. It is most often found in landscape areas, container-grown plants, and greenhouses. Its stems branch at the base and can achieve a height of 12 inches. Growing on the central leaf stem is 2 to 4 pairs of leaflets that are alternately arranged. Each leaf occurs on a petiole that is distinctly hairy. One should take note that the upper leaves will be noticeably more hairy than the lower leaves. This weed flowers in clusters while each individual flower is small (2-3mm) and composed of 4 white petals. The fruit (seed capsule) is a silique, which is a long, narrow capsule with many seeds. Siliques can explosively spread the seed as far as 10 feet from the parent plant. It tends to grow in disturbed soils and will form dense mats of rosettes over an area.
Hairy bittercress has long, narrow siliques and round leaflets that are alternately arranged. Also, this weed has white flowers with 4 petals in dense clusters at the end of the stem.
Improving drainage can be a great way to deter this moisture-loving weed. If you have severe infestations of hairy bittercress, it may require chemical treatment. Post emergence herbicides such as 2-4 D, triclopyr, clopyralid, dicamba, or MCPP should be used.
Finally, don’t forget that wild hairy bittercress is edible! It is best to gather in early spring or late fall when the leaves are tender. It adds a peppery bite to raw salads, and can be cooked and added to soups.
Authors: Jed McCoy, Corey Garrison, Justin Hickman
What is Chamberbitter?
Chamberbitter (Phyllanthus urinaria) is a member of the Spurge family (Euphorbiaceae), sometimes referred to as gripeweed, leafflower, or little mimosa. It is native to Asia, but has found its way across the southeast and into Texas. Chamberbitter is a warm-season broadleaf annual and usually emerges around May or June when the soil temperatures have warmed to approximately 70oF. It spreads by seeds that are located on the bottom side of the branch. Ornamental beds and turfgrass are the two most common places to find Chamberbitter. In South America, this plant is believed to be good for medicinal purposes; specifically, treatment of kidney stones.
What does Chamberbitter look like?
Chamberbitter can grow tall and thin, which can be aesthetically unpleasing. The leaves grow in two alternating rows. Leaves are thin and smooth which resemble the seedling of a mimosa plant. It is best identified by the fruiting structures on the underside of the branch which produce numerous seeds. These seed capsules can explode and spread seeds over a large area. Also, like some spurge, if you break the stem, it will produce a milky white sap.
How do I control Chamberbitter?
Chamberbitter can be a difficult weed to control. It is drought tolerant and grows rapidly. Seeds on the underside of the plant can be produced in as little as two weeks. If making a pre-emergent herbicide application, Chamberbitter control is often unreliable because it germinates later in the spring than most summer annual weeds.
- Frequent mowing
- Hand pulling
- In landscape beds, 1-3 inch mulch layer will block seed from receiving light
- Three-way herbicides containing dicamba, 2,4-D, mecoprop (MCPP)
- Isoxaben (Gallery 75DF)
Christo Sullivan, Doug Martin, Jordan Billingsley
About – Yellow Woodsorrel (Oxalis stricta) is a medium-sized edible plant that thrives in lawns and woodlands across the United States and Canada. It can also be found in Europe, Africa, Asia, Japan and New Zealand. The flowers can be used to make yellow, orange, red and brown dyes. Another common name is “Oxalis”, which means “sour” due to its oxalic acid content. Oxalic acid can be toxic when consumed in large quantities because it inhibits the absorption of calcium. Yellow Woodsorrel is a cool season perennial in the Woodsorrel family (Oxalidacea), but may act as a summer annual in certain environments. It reproduces by seed and occasionally stems.
Identification – Yellow woodsorrel introduces itself from a taproot and forms small, erect, bushy plants up to 20 inches tall. The stems are slender, gray-green, pubescent, slightly ascending, and branched at the base. They will occasionally root at the nodes. The leaves of yellow woodsorrel are alternate with three heart-shaped leaflets. They are pale green, up to 4/5 inch across with long petioles. The flowers are yellow with five petals and are up to ½ inch across. It is often mat forming and more common in cools-season turf species, such as tall fescue. It can be very common in greenhouses and container nurseries because its seedpods can distribute seeds up to several feet.
Cultural– Hand-weeding is effective before seeds are formed. As always, the best weed control is a dense turf sward. Proper mowing, fertilizing and irrigation ensure vigorously growing turf.
Many pre and post-emergent herbicides are effective.
Pre-emergent herbicides include:
Post-emergent herbicides include:
And many 3-way mixtures sold at in lawn and garden sections (often labelled as Trimec Southern or for Broadleaf weed control).
by Michael D. Denney, Dylan Botelyr, and Wes Dyer
Identification: Buckhorn Plantain is a rosette-forming perennial herb with leafless, hairy flower stems. The fruit is composed of egg shaped capsules 1/6” long containing either one or two seeds per flower. Leaves are football shaped and stand between three and 10 inches long with short hairs that spiral around the stem. The stalks grow upwards of 2 to 2.5 inches and have a dominant, strong taproot.
Characteristics: Buckhorn Plantain is characterized as being drought tolerant. Typically, the plant reproduces via seed and disseminated through airborne carriers or water. The seeds are oblong shaped and brown with one side having a glossy, light brown stripe.
Habitat: Environmental conditions favoring the growth of Buckhorn Plantain are vineyards, orchards, gardens, urban areas, turf, foot paths, and crop fields in general. Typically, Buckhorn Plantain prefers areas that have been plowed or disturbed in any manner.
Control: Control of Buckhorn Plantain consists of two measures, either pre-emergence or post-emergence herbicides. For pre-emergence control, Isoxaben is a good choice for minimizing germination. Post-emergence control includes 2,4-D, Triclopyr, MCPA, and MCCP. Typically, 2,4-D has good activity on Buckhorn Plantain, while Triclopyr, MCPA and MCCP reduces plant vigor. Buckhorn Plantain can be a difficult weed to control, but combining cultural practices, such as hand pulling, and herbicide use is the best approach for control.
by Ashley Averitt, Justin Hickman, and Kyle Grider
Star-of-Bethlehem belongs to the Lily family (Liliaceae), which is closely related to wild garlic and wild onion. It has origins as a cool season perennial ornamental plant, but it has grown into an aggravating weed in home lawns, golf courses, and athletic fields. This plant spreads by seeds and underground bulbs. It emerges in the winter to early spring and flowers as temperatures increase, but once summer arrives the plant will enter dormancy. This plant may be poisonous to grazing animals because it contains high levels of cardiac glycosides, especially in the bulbs.
Often confused with wild onion and wild garlic, Star-of-Bethlehem can be distinguished by darker green leaves, a pale green to white mid-rid, and is covered with a waxy coating. When Star-of-Bethlehem is crushed or mowed it does not produce a strong odor. Leaves are narrow and linear and will blossom a white, six petal flower with distinct green stripe underneath the petals in the spring. Star-of-Bethlehem mainly produces from bulbs and rarely from seeds. The bulb of Star-of-Bethlehem is noticeably larger than that of wild onion and wild garlic.
How to control Star-of-Bethlehem?
- Mowing: prevents flowering and seed production. Come winter, be sure to raise the height at least 2 inches.
- Hand picking, constantly, but make sure you pull out the entire bulb and bulblets.
The following postemergence herbicides are available:
Dismiss and products containing Sulfentrazone have been shown to act more rapidly than other products.
- Dismiss (active ingredient (a.i.)sulfentrazone)
Rate/acre = 8-12 oz/A
- Q-4 (sulfentrazone + quinclorac + 2,4-D + dicamba)
Rate/acre = 7-8 pints/A
- RoundUp Pro (glyphosate) + Mowing (in dormant turf)
- QuickSilver (a.i., carfentrazone)
Rate/acre = 2.1 oz/A
- Surge (a.i.’s, sulfentrazone + 2,4-D + MCPP + dicamba)
Rate/acre = 3 to 4 pints/A
Non Residential Turf:
- Buctril (bromoxoynil)
Rate/acre = 1-2 pints/A (2EC) or 0.5-1.0 pint/A (4EC)