It is important to control weeds in pineapple farm (Ananas comosus) during the first four months after planting so as to avoid slow growth of pineapple plants which could arise as a result of competition for space, nutrients and air with the crop.
It is advisable that a A pre-emergence application of Atrazine @ 4kg a.i/ha is is to be applied immediately after planting in other to block the germination of weed seeds for as long as possible.
Thereafter, a tank mixture of Atrazine and diuron can be used subsequently for weed control in pineapple. Meanwhile, weeding in a pineapple farm is done at least three to four times with a growing season to prevent the farm from being overtaken by weeds.
Weeds within pineapple fields constitute one of the deterrents to maximum growth and yield, as they compete for available plant nutrients, soil moisture and sunlight. Less obviously, they facilitate the increase and spread of insect pests and nematodes which invariably damage the pineapple.
Weeds also interfere with in-field operations, such as dry fertilizer application, harvesting, sucker selection and seedpiece gathering. Dominant weeds of pineapple and species shifts therein are noted.
Weed management in pineapple is especially important during early growth, because weeds compete for water, nutrients and light, are hosts for pineapple pests and viruses and interfere with production operations.
Weed management includes soil tillage, mulches, and the use of pre-emergence (applied prior to weed-seed germination) and post-emergence herbicides.
The efficiency of the pineapple weed-management system is affected by plant density, the degree of mulch cover, soil type and natural rainfall and/or the method of irrigation.
Because the pineapple plant is relatively slow in establishing a complete ground cover, eliminating weed cover may result in high levels of soil erosion
Weed control can be done manually in the rows and mechanically between the rows. During harvest weed control needs to be especially well done in the rows parallel to the planting lines because the fruits are usually collected from the ground.
Mechanical weeding (close to the plant less than one meter) is not recommended in order to prevent damages to the roots, which are largely concentrated within 15 to 45 cm from the stem.
Chemical weeding, using selective herbicides eliminates not only the weeds, but reduces operational costs and simplifies the work.
The best pre-emergence herbicides are “diuron” and “bromacil”. Paraquat or glyphosate have been used in some plantations at 1.5 to 2.0 l/ha, and applied between the rows, leaving the dead weeds as a form of mulch covering the soil surface.
While studying the selectivity of pre-emergence herbicides “diuron” (1.2, 2.4 and 4.8 kg/ha), “oxyfluorfen” (0.48, 0.96 and 1.92 kg/ha), “alachlor” (2.8, 5.6 and 11.2 kg/ha) and “atrazine” + “metolachlof (3.0, 6.0 and 12.0 kg/ha), in yellow passionfruit seedlings, observed that only “atrazine” + “metolachlor”, in doses of 6.0 and 12.0 kg/ha, caused serious injury to the seedlings, while the others proved promisingly useful.
Due to the fact that herbicide activity, in general, is limited to a specific plant or group of plants, it is recommended to use mixtures and planned combinations of herbicides pre-emergence and post-emergence, aiming to increase the period and active spectrum of the chemical control.
Pineapple Weed Information
Pineapple farm weed (Matricaria discoidea syn. Chamomilla suaveolens) is appropriately named for the small, greenish-yellow, cone-shaped flowers that grow atop sturdy, hairless stems. When crushed, the leaves and flowers emit a sweet, pineapple-like aroma.
The leaves are finely cut and fern like. Although pineapple weeds belong to the aster family, the cones have no petals. Reportedly, the small, tender buds are tasty added to salads, brewed as tea or eaten raw, but be careful, as some people may experience a mild allergic reaction.
Pineapple weed plants resemble various other less palatable weeds, so before you taste, be sure you can identify the plant by its sweet, fruity aroma. Pineapple weeds reproduce only by seeds.
The small seeds are rather gooey when wet, which makes managing pineapple weeds especially challenging. The gelatinous seeds can stick to passing animals and can also be dispersed by water and by human activity, such as mud stuck to tires and boot soles.
How to Kill Pineapple Weed
Complete control of pineapple weed is difficult but, fortunately, the roots are shallow and relatively easy to pull. Be persistent, as it may take several attempts before the weed is eradicated. If the ground is hard, soak it the day before to make pulling easier.
Read Also: How and when to Fertilize a Pineapple Farm