Sandbur Control Part 1
Sandburs are one of the most asked about topics in the Payne County Extension office. It is too early to do anything right now for sandbur control but we need to go ahead and talk about it so you can formulate your action plan for this growing season. As in all things plant related, there are exceptions, but the following information should pertain to most of you dealing with this problem. If you have any questions, please don’t hesitate to contact our office.
It is important to understand that sandburs are grassy weeds. In other words, they are much more closely related to your turf grass than most of the common weeds in your lawn. This means products labeled for control of broadleaf weeds such as dandelion, chickweed, spurge, etc. will offer no control of this plant. To compound the problem, there are very few cost effective post-emergent grassy herbicides (post- meaning the product is to be used after the weed comes up) available for use to the homeowner.
Even when properly applied, herbicides are only marginally effective unless care is taken to maximize the competitive advantage for your turf grass. Strong healthy turf is your best defense against sandburs. Check back next week and we will discuss this component in greater detail.
With that being said, the best chemical control option is the proper application of a good pre-emergent herbicide labeled for control of sandburs. As the name implies, these products must be applied (and activated with rainfall or irrigation) before the weed germinates. All the products that control sandbur also control crabgrass, so applying the product in time to control crabgrass as well is the prudent thing to do.
The exact time for spring weed germination is hard to pin down because of weather fluctuations but March the 15th as a good time to plan your first pre-emergent application. If you prefer to let mother nature guide you instead of the calendar, make sure you apply these products as the redbuds are just passing their peak bloom cycle or the forsythia plant begins to drop its brilliant yellow blooms. This bio-indicator is a sure sign that crabgrass will be germinating soon.
When shopping for herbicide, look for products containing the active ingredient pendamethalin or oryzalin. As with all pesticides, it is very important to read the label and follow the instructions carefully. Failure to do so will result in less than desired results at best and damage to your desirable landscape or the surrounding environment at worst. For example, some of these products will offer season long control on crabgrass yet will fail to prevent sandburs unless a follow-up application is made later in the growing season.
For more information on this or any other horticultural topic, you can contact Keith Reed, the Horticulturist in the Payne County Extension office. Keith can be reached via email at email@example.com, phone at 405-747-8320, or in person at the Payne County Extension office, located at 315 W. 6th in Stillwater.
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