Maintenance of the lawn: how to control, remove and eliminate weeds from grass
With time, weeds start growing and attack the grass, hindering the growth of grass. Weeds can grow at small spots and may spread out quickly forming a low and/or dense bushes making your lawn to look ugly.
Which type of weeds are the most common?
There are several types of weeds. The most common weed in Brazil are Capim do Brejo, Capim da Roça, Tiririca, Trevos, Dente de Leão, Hera terrestre, Sempre-Noiva, Braquiara, Morrião dos Passarinhos, Beldroega, Azedinha, Capim Colchão among others.
Which type of weed is the most difficult to eliminate?
Among all different types of weeds, the main, most common, and most feared one is known as “TIRIRICA”, whose scientific name is Cyperys rotundus.
Tiririca presents a group of bulbs, rhizomes and an underground tubercle (also known as “little potatoes” or “batatinhas” in Brazil) which are linked as a chain where leaves and flowering stems grow (see image below).
The tubercles are produced in the rhizomes and when they sprout, one or more gems grow, producing new plants with more tubercles, which guarantee the reproduction and spread of the Tiririca.
Therefore, once the lawn gets infested with Tiririca, it requires a lot of work to remove it and its elimination becomes harder.
How weeds appeared in my lawn?
The spread of weeds may happen from organic matters and contaminated seedlings, agricultural equipment with tubercles (“batatinhas” or “small potatoes”) adhered to it, or can be brought from flooding, and irrigation channels.
How to control weeds, especially Tiririca?
The control of weeds can be done mechanically or chemically.
The mechanical method for the weeds removal, including Tiririca, is done through the soil preparation, trimming and the cultivation of antagonistic species.
The chemical method is the most efficient way to remove the weeds. It is done through selective herbicides that kill the weeds but not the grass. For each type of weed, there is a specific type of selective herbicide that can be acquired in shops specialized in agricultural products and pesticides.
In the case of Tiririca, herbicides known as pre-emergence herbicides such as Alaclor, Metolachlor and EPTC followed by the use of post-emergence herbicides such as Imazapir (sold in the market at 2.5%, named as Kapina), the 2,4D (2,4-dichlorophenoxiacetic acid) and the Glyphosate (N-phosphonomethyl glycine, C3H8NO5P) that can be used in the first weeks after the emergence of Tiririca in the lawn.
Preventing the spread of weeds is the best way to control it. Therefore, as soon as you see the weeds growing in your lawn, try to eliminate them as quick as possible.
The selective herbicides are toxic chemical products that require controlled handling. Therefore, if you need to buy them, you need a special orientation and prescription from an agronomist.