Photos by GCMGA By MG Marian Kimbrough Weed of the Month (April 2009): Bur Clover Class of 2007

A common clover- and purple stems. It germinate. While weed type plant that grows reproduces from seeds and feed fertilizers for Common Scientific in this area and is quite contained in “burred” lawns can be an effective Name Name invasive is known seedpods, as well as tool, they can stress or kill Large Bur Clover Medicago polymorpha as bur clover. Even spreading prostate landscape trees and shrubs though it is not a true stolons, which allow it if applied under or near Small Bur Clover Medicago minima clover, two species to tolerate close mowing, their drip line. identified in this area increasing its survival Over-the-top herbi- are commonly known and spreading abilities. cides or post-emergence damage the grass or other When using as large bur clover The exterior of burred herbicides like “broad- green, living plants that it herbicides and other (Medicago polymorpha) seedpods have numerous leaf weed killers” may be touches. Be sure to read pesticides, always and small bur clover velcro-like hooks that used in the spring. If you and follow the product’s read and follow label (Medicago minima). may become entangled in choose to use a post- label instructions and directions carefully. Both species are dicots animal coats or human emergence herbicide, do precautions. (broadleaf plants) in clothing, which serves so when the bur clover is the legume family and as a common means of actively growing. Apply a are closely related to dispersal. broadleaf lawn herbicide the true clovers. Large Preventive practices, containing a combina- bur clover and small such as good turf man- tion of 2,4-D and MCPP bur clover are native agement, are best in re- or triclopyr as its active to Europe but brought ducing infestation. Here ingredients late May or to the States as grazing in the Gulf Coast area, early June. More than one material (fodder crop) a lawn fertilization pro- application may be neces- for cattle. gram based on soil tests sary. To be most effective, Large bur clover will encourage growth the herbicide should be can grow from 6—22 of a dense, healthy turf, applied when tempera- inches and has flower which will inhibit the tures are between 60—80 clusters consisting of clover from becoming degrees, no rain is forecast 3—5 flowers, bloom- established. Mechanical for 24—48 hours, and no Bur clover can be readily identified by its small pea- ing in early spring. or physical removal is not wind is present to blow like yellow flower, three green clover-shaped leaves Small bur clover can recommended because the herbicide onto desir- and purple stems. grow from 6—18 stolons may break and able broadleaf plants. inches long with 10 or sprout, increasing rather For spot treatment of more flowers displayed than decreasing the infes- small, unwanted patches, per head (inflores- tation. you can avoid the use of cence). In this region, Pre-emergent herbi- a tank sprayer by mixing bur clover’s blooming cides like those con- the herbicide according period is from Febru- tained in “weed and feed to label directions and ary to June but can fertilizers” may be used to then applying it with a grow year round. Ger- prevent seed germination disposable paint brush or mination is in the fall in the fall. Timing of the a sponge tied to a stick. season when tempera- application is critical for Glyphosate (Roundup) tures are cooler. effective control. Early works well for this since Bur clover can be October is recommended the area may be reseeded readily identified by its as cool fronts typically seven days after applica- small pea-like yellow occur during this time tion. Be aware, though, The exterior of burred seedpods have numerous velcro- flower, three green and the seeds of cool that glyphosate is non- like hooks that may become entangled in animal coats clover-shaped leaves season weeds start to selective—it can kill or or human clothing which aides its dispersal.