Extension‐Wise
Published Weekly in the Madison County Journal Thistle, Dandelion, and Plantain Weed Control June 21, 2012 I’m sure you remember that scene from The Wizard of Oz when Dorothy and her companions are traveling through the woods and they’re overly terrified of such things as lions, gers, and bears. I’ve been quite terrified myself the last couple of months driving along and no cing some weeds that have started to seriously take over pastures, hayfields, lawns, and open lots. Dandelion, this‐
tle, and plantain are three weeds I’ve been seeing all too regularly and I’m becoming concerned that many of our pasture and hay‐
fields will soon be completely overrun. Dandelion is probably the most well‐known of the three because of its bright yellow flower and persistence in home lawns. To be honest, the weed is most likely Carolina false dandelion, but that’s another ar cle for another week! Regardless, it develops a fluffy white seed head that disperses by wind and can grow nearly year round. It is a perennial weed which means the same plant will live for several years producing seed. It has a taproot that can reach more than 2 feet in the ground o en outcompe ng turf roots for water and nutrients. In small numbers, dandelions can be pulled or dug up. However, when le unchecked, dandelions will quickly grow into large enough numbers that use of herbicides becomes the most efficient way to handle the problem. Dande‐
lion can be easily killed by most common homeowner herbicides such as 2,4‐D, dicamba, and even triclopyr. Farmers can use other products such as Crossbow, GrazonNext, and Weedmaster. Plantain is a group of plants that are also a major problem. The most common one I’ve no ced is buckhorn plantain, which is a low
‐growing plant with ellip cal leaves and a flower stalk that looks like a small cone. Plantain is also a perennial which produces by seed and new seeds will begin germina ng once soil temperatures are above 50°F and con nue germina ng throughout most of the year. I’ve seen this plant quickly take over lawns and hayfields and completely shade out grasses. Newly sprouted plants can be controlled with postemergent herbicides like 2,4‐D and triclopyr but once plantains become established it is more difficult to control. You can s ll experience moderate control with 2,4‐D once plants become established but it is best to start controlling this weed before it becomes widespread. Of all the weeds I’ve seen this spring and summer, thistle is one I’m most concerned with just because of the incredibly large num‐
bers I’ve been seeing in open lots and on the sides of the road along with what I’ve seen in open pastures and fields. Thistle grows in a similar fashion to both dandelion and plantain with a low‐growing rose e of leaves but thistle will have sharp ps on all the leaves and can become a problem with livestock. Thistle is a biennial plant. This means that it has a two‐year growth cycle. The first year the plant is low to the ground and is hard to spot without careful scou ng. The second year the plant will “bolt” star ng in January and will soon develop the bright pink flower that is so easily visible from the road. This pink flower will develop into a white seed head and will disperse large numbers of seed. Like dandelion and plantain, 2,4‐D can be an effec ve control along with other products such as Milestone, Chaparral, Grazon (Next or P+D) and Crossbow. With all three of these weeds, especially thistle, ming of herbicide applica on is important. When any plant is young and ac vely growing, it is most suscep ble to herbicide applica on. When plants start moving from a stage of vegeta ve growth to reproduc‐
ve growth (seed produc on) they’re biological ac vity slows. This is why some mes herbicides applica ons some mes aren’t as effec ve when weeds are sprayed later in their maturity. It takes extra effort in scou ng of fields, but no cing when these plants are young and first emerging (late fall and early spring) provides the best me to spot or broadcast spray and expect most effec ve results. It is also some mes beneficial to mow large areas of weeds that are star ng to develop seed to prevent a large problem from becoming worse. There are so many different op ons and combina ons when it comes to herbicides and chemicals that a short news ar cle doesn’t quite cover all the poten al choices and details. Always look at a chemical label to make sure it is to be used in your situa on and use proper safety when handling chemicals. You can always call the Extension office for more specific help as well.