It is not too early to think about controlling potential weed problems in alfalfa and small grain fields. Right now there are winter annual and biennial weeds actively growing in most of the regions alfalfa fields. These weeds are often responsible for the lower forage and feed quality of first cutting alfalfa. This is unfortunate because the first cutting of alfalfa often represents nearly half the crops total annual yield, and these weeds are relatively easy to control.

Winter annual and biennial weeds include such favorites as wild turnip, yellow rocket, chickweed, red dead nettle, pepperweed, mustard, henbit and some species of thistles. All of these beauties can be found in abundance in many farm fields around the region. In the spring they will produce a sea of lovely colors that include bright yellow, pink, red and blue. It is much easier to control these weeds when they are small. When they have matured and are noticeable above the crop and you see the colorful blooms, it is too late to control them. There are severe economic losses and penalties for weeds in small grain.

Use the time between now and late winter to determine if there is a weed problem in the alfalfa and small grain fields. Make an effort during this time period, when the fields are not snow-covered, to walk around the fields to check the extent of any weed infestations. The earlier that a decision is made on the condition of a field, the easier it will be to make plans for applying an herbicide for weed control. In most instances the herbicide can be applied with the late winter, early spring fertilizer application. This will save time and money.

Starting early in the planning process will allow for some research on what herbicide will be best for the farm management situation. The herbicide label has a wealth of information that can help to make a sound decision. For example, some herbicides have restrictions on soil and air temperature for spraying, and some require the alfalfa to be dormant. Some are deadly to grasses and are not labeled for mixed alfalfa and grass stands. Some have long residuals in the soil that can affect future crop rotations. For example, if the herbicide Sinbar, or Velpar is used in alfalfa, both not only kill existing weeds but also have long residuals in the soil to prevent the growth of new weeds, especially grasses; this would prevent rotating to corn, or inter-seeding a forage grass for up to two years depending on which one is selected. Management decisions such as this are too important to make at the last minute.

There are several different types of herbicides on the market to select from. Some kill only broadleaf weeds while some kill only grasses, and some will kill both types of weeds. Some products kill the weed on contact and some are systemic, killing the weed down to its roots. Each of the herbicide products will be more effective on a certain group of weeds than another product. It is up to the producer to determine, if there is a weed infestation, what weed species are present, what is the future crop rotation plan for the field, and lastly, what is the best herbicide product to use. The county office of the University of Maryland Extension and the local farm supply dealers can assist with weed identification and product selection.

Source - http://www.fredericknewspost.com/