These diverse terrains, warm temperatures, seasonal rains, and nutrient-rich soils shape both the bounty of the crops and the growth of native and invasive weeds. 

The weeds compete for space and other important nutrients, and in some cases, they can spread aggressively on farmlands and natural habitats. 

Here, we explore the 25 most common weeds in Zambia, describing where they thrive, their unique features, and the best methods to remove them. 

1. Purple Nutsedge (Cyperus rotundus)

• Local Name: Purple Nutsedge
• Family: Cyperaceae
• Annual or Perennial: Perennial 

Purple Nutsedge is a perennial weed that can grow up to 1m high. It is commonly found in maize and rice fields, and permanent or seasonally wet areas. 

You can identify the weed by its thick and stiff leaves arranged in sets of threes from the base. The spikelets (3-15) are reddish to purplish brown, slightly flattened, and arranged on dense clusters.

Removing the young plants before they develop tubers is the best strategy to reduce the sedge population. Aim to dig out the plants before they develop 5-6 leaves, and eventually the reserves will dry out. 

Increasing shade and improving irrigation practices to prevent unnecessary waterlogging conditions can also help control Purple Nutsedge. 

2. Blackjack (Bidens pilosa)

• Local Name: Nakasopyo, Sokotela, or Kanunka
• Family: Asteraceae
• Annual or Perennial: Annual

Blackjack is an annual to short-lived perennial that can be found in gardens and potatoes, beans, and cotton fields. 

The upright herb has opposite leaves and distinct barbed seeds that cling to animal fur and human clothing.

While it is known to be a beneficial vegetable with numerous anti-inflammatory and skin benefits, Nakasopyo is also considered a pesky weed in Zambia.

Mechanical control methods like manual weeding when the plants are small, mulching, and intercropping are enough to eradicate the weeds. However, if you’re dealing with large infestations, simazine and glyphosate products can provide effective control.

3. Napier Grass (Cenchrus purpureus)

• Local Name: Napier Grass, Elephant Grass, Uganda Grass, or Senjele
• Family: Poaceae
• Annual or Perennial: Perennial 

Napier Grass is a perennial clumping grass that forms dense stands up to 4m tall. It is commonly grown as a forage, hay, and silage crop for feeding livestock. 

However, Elephant Grass can be invasive in irrigation systems, fallow lands, and riparian areas. Cutting and digging to remove the rhizomes, followed by glyphosate applications for regrowth, will remove the grass. 

4. Giant Salvinia (Salvinia molesta)

• Local Name: Kariba Weed 
• Family: Salviniaceae
• Annual or Perennial: Perennial 

The weed is named after its common sighting in Lake Kariba along the Zambezi River. Salvinia molesta is a troublesome aquatic fern that forms dense mats on water surfaces. 

The mats block oxygen and sunlight, choking fish and other aquatic plants. Additionally, the vegetation also impedes fishing, boating, and swimming, and also clogs irrigation channels. 

Despite eradication efforts such as the introduction of weevils, herbicide applications, and other long-term strategies, the weed has proven difficult to eradicate due to its highly invasive and troublesome nature. 

5. Couch Grass (Cynodon dactylon) 

• Local Name: Couch Grass
• Family: Poaceae
• Annual or Perennial: Perennial

Couch Grass is a native perennial grass that forms dense mats through underground runners and spreading rhizomes. 

In Zambia, it is a common weed in maize fields, roadsides, and pastures. Some farmers use improved varieties as pasture, but the wild form is often considered a serious weed due to its quick spreading habit and competition with crops. 

Hand-pulling may be viable for small infestations, while repeated cultivation and herbicide treatments may be needed for larger infestations. 

6. Wandering Jew (Commelina benghalensis)

• Local Name: Wandering Jew, Bhengal Wandering Jew, or Benghal Dayflower
• Family: Commelinaceae
• Annual or Perennial: Annual or Perennial 

Wandering jew is an annual or perennial weed with succulent stems and blue flowers, and can grow up to 1m tall. The weed invades grasslands, roadsides, open woodlands, and disturbed sites. 

It is also considered a serious weed of cultivated root crops and vegetables. Wandering Jew is also a known host for destructive viruses and pests, potentially adding more agricultural damage. 

Pulling out the young plants is possible, but only effective if all the roots and underground flowers are removed. 

Multiple herbicide treatments are often required to treat seedlings, while the mature plants have shown persistent resistance to glyphosate and other products.

7. Pigweed (Amaranthus spp.)

• Local Name: Pigweed
• Family: Amaranthaceae
• Annual or Perennial: Annual 

Several species of Pigweed can be found in various natural habitats and cultivated fields in Zambia. These robust annuals are a favorite vegetable, but they are also competitive pests in maize fields. 

Hand-pulling or hoeing the young plants is typically effective, as they are often cooked as a vegetable.

8. Goosegrass (Eleusine indica)

• Local Name: Kalolo or Lukata
• Family: Poaceae
• Annual or Perennial: Annual 

The tufted annual grass is a common weed in Zambia’s crop fields, roadsides, pastures, stream banks, and landscapes. 

It is easily identified by its finger-like seed heads, flat or folded leaves along the central vein with a boat-shaped tip, and trailing or erect stems, up to 40 cm high.

Early planting and tillage, intercropping with legumes, and minimal grazing will control the weeds in crop fields. 

Repeat herbicide applications are required to control larger infestations in landscapes and other areas. Ensure to rotate the recommended products to avoid the development of resistance populations.

9. Purlsane (Portulaca oleracea)

• Local Name: Common Purslane
• Family: Portulaceae
• Annual or Perennial: Annual

Common Purslane is an annual weed that can be commonly sighted in gardens and disturbed areas. It is a prostrate, succulent herb with small, broadly rounded leaves, bright yellow flowers, and stems that reach a height of 30 cm. 

While it is a beloved vegetable in many parts of the country, it can also become a pesky weed if unwanted.

To effectively control Purslane, pull or hoe the plants while young or apply mulch in your garden to limit growth and spread. 

10. Witchweed (Striga hermonthica)

• Local Name: Witchweed, Purple Witchweed, or Striga
• Family: Orobanchaceae
• Annual or Perennial: Annual or seasonal 

Witchweed is perhaps among the top dreaded weeds in Zambia. It can be traced to areas with poor rainfall and low soil fertility, including the Luangwa Valley and parts of the Southern Province.

The weed is parasitic, which means it attaches to important crops such as maize, millet, and sorghum. Striga deprives the host plant of valuable resources, causing direct damage such as stunted growth which ultimately leads to poor yields.

Once you identify the weeds, pull them out to prevent seed set for future regrowth control. Farmers are encouraged to plant certified seeds or crop varieties that are tolerant to imazapyr for effective control. 

You can refer to this CABI document for more Striga hermonthica prevention measures in maize systems.

11. Visepo (Lantana camara)

• Local Name: Visepo 
• Family: Verbanaceae
• Annual or Perennial: Perennial 

Visepo is an aromatic perennial shrub that can grow up to 2m tall. It can be found in many provinces, including Lusaka, the Northern Province, North West, West, and the Southern Province. 

Lantana camara is a serious invader of overgrazed sites, woodlands, formerly cultivated lands, and other disturbed sites.

It is listed among the world’s worst alien invasive species for its rapid spread, high adaptability, and the extensive negative impact it has on native vegetation. 

Mechanical removal is viable for small infestations or at an early growth stage of a moderate infestation. Cutting the shrubs and combining it with a non-selective herbicide application can provide better control for larger infestations. 

12. Yellow Nutsedge (Cyperus esculentus)

• Local Name: Cyperus esculentus
• Family: Cyperaceae
• Annual or Perennial: Perennial 

Yellow Nutsedge is a perennial weed that can be distinguished by its triangular stems and yellow-brown spikelets. 

It is a common weed of gardens, crop fields, riverbanks, roadsides, irrigation canals, and disturbed areas. If left to establish, it can be a tough weed to eradicate due to its underground root network. 

Hand weeding provides effective control if all the tubers are removed. Postemergence herbicides containing ingredients like glyphosate, sulfentrazone can be applied to control Yellow Nutsedge.

13. Broadleaf Plantain (Plantago major)

• Local Name: Broadleaf Plantain or Broad-leaved Plantain
• Family: Plantaginaceae
• Annual or Perennial: Perennial 

Broadleaf Plantain is a low-growing perennial herb that can be identified by its ovate leaves that form a rosette and elongated spikes with reddish-brown capsules. 

In Zambia, it is both an agricultural and an environmental weed, mainly found in row crops, gardens, pastures, and disturbed areas. 

The weeds can be removed by pulling or digging, mulching, or application of non-selective herbicides like glyphosate. 

14. Water Hyacinth (Eichhornia crassipes)

• Local Name: Water Hyacinth or Kafue Weed
• Family: Pontederiaceae
• Annual or Perennial: Perennial 

The world’s worst water weed can be found in lakes and rivers such as Kafue and Zambezi.

The invasive floating weed has caused both socio-economic and ecological problems, including choking waterways, clogging hydroelectric stations, impeding transport and fishing, and harming aquatic life. 

Since the weed thrives on nutrient-rich waters, several companies have since stopped discharging irrigation runoff into the waters to reduce the weed populations.

Fencing off water intakes and recurring manual removal by locals are typically the most effective and economically sustainable strategies to deal with water hyacinth.

15. Bristly Starbur (Acanthospermum hispidum)

• Local Name: Bristly Starbur
• Family: Asteraceae
• Annual or Perennial: Annual 

Bristly Starbur is an annual erect herb that can grow up to 60 cm. You can identify the weed by its stiff, white hair-covered stems, oblong lanceolate leaves, and small, creamy-yellow flowers. 

It is commonly found in crop fields, pastures, roadsides, disturbed land, and waste areas in the Eastern, Western, Lusaka, and Luapula provinces. 

Apart from outcompeting native plant species and contaminating produce, the leaves and seeds also produce allelopathic properties that inhibit the growth of other plants.

Hand-pulling or hoeing is effective for removing weeds in fields if done before seed set. Herbicides like glyphosate can effectively remove larger infestations.

16. Common Cocklebur (Xanthium strumarium)

• Local Name: Common Cocklebur
• Family: Asteraceae
• Annual or Perennial: Annual

Common Cocklebur is an annual herb with spiny burs that stick to animals and clothing. You can also identify the weed by its triangular, three-lobed leaves with a distinct scent. 

This weed is commonly found in the Southern Province, which experiences extended drought seasons and hosts some semi-arid areas. 

However, since it can grow in most environments and tolerate various soil types, Common Cocklebur can also be found in landscapes, agricultural fields, disturbed sites, and streambanks.

Pulling out by and is viable for small infestations and only if done before bud development and seed dispersal. Ensure that you wear protective clothing as the burs can cause dermatitis.

For larger infestations, locals use selective and non-selective herbicides like triclopyr, metsulfuron, and glyphosate, depending on the infested area. 

17. Mexican Clover (Ricardia scabra)

• Local Name: Mexican Clover
• Family: Rubiaceae
• Annual or Perennial: Perennial

As the name implies, the weed grows in warmer climates across the Americas and African countries, including Zambia’s Central, Southern, and Western provinces. 

The weed can be distinguished by its elliptic to lanceolate leaves and 6-petaled, white flowers with triangular lobes. Mexican Clover is a common weed of cultivated land, roadsides, and disturbed sites.

Pull out or dig the weeds using a trowel if you’re dealing with a small area. Ensure to remove the entire taproot to prevent regrowth.

Herbicides like dicamba, metsulfuron, and glyphosate provide effective control if applied on young, actively growing plants.

18. Johnson Grass (Sorghum halepense)

• Local Name: Johnson Grass
• Family: Poaceae
• Annual or Perennial: Perennial

Like many other parts of the world, Johnson Grass is also a troublesome and persistent weed in Zambia. The tall perennial grass spreads by rhizomes, invading crop fields, irrigation canals, abandoned fields, roadsides, streambanks, and waste areas. 

Pull out the young grass when the soil is moist to remove all the rhizomes. Ensure the removed plant fragments are disposed of correctly to prevent resprouting. 

A glyphosate product can eradicate the grass in non-crop areas. Consult a local extension expert on the recommended postemergent herbicides for Johnson Grass in cultivated lands.

19. Morning Glory (Ipomoea purpurea)

• Local Name: Morning Glory
• Family: Convolvulaceae
• Annual or Perennial: Annual 

Morning Glory is a trailing or climbing annual weed with showy purple flowers. It is commonly found in farmlands, gardens, roadsides, fencelines, streambanks, and waste areas. 

The weed can be located in the Copperbelt region, the Northern, Western, and Lusaka provinces. Not only does it outcompete desirable crops, but it can also outgrow native vegetation, severely impacting many habitats. 

Fortunately, the weed and its roots are easy to pull or dig all year round. Alternatively, cutting and spot-treating the remaining fragments with the locally recommended herbicides can also effectively control Morning Glory.

20. Wireweed (Sida acuta)

• Local Name: Wireweed, Common Wireweed, or Spinyhead Sida
• Family: Malvaceae
• Annual or Perennial: Perennial 

Wireweed is a long-lived herb or small shrub that can grow up to 100-150 cm tall. You can identify it by its wiry and tough stems, elongated, yellowish-green leaves with serrated margins, and small yellow to orange flowers.

Common Wireweed is commonly found in crop fields, gardens, pastures, and disturbed sites, mostly in Lusaka Province.

If you prefer hand-pulling, ensure that you grasp the weed close to the base and pull firmly, preferably when the ground is moist. Goat grazing is also practiced as the ruminants love to eat this weed. 

21. Garden Spurge (Euphorbia hirta)

• Local Name: Garden Spurge or Asthma Plant
• Family: Euphorbiaceae
• Annual or Perennial: Annual 

The prostrate or ascending Garden Spurge is a common weed in Zambia’s agricultural areas, gardens, roadsides, and disturbed areas. 

It is easily identified by its round, hairy, reddish stems and oblong to lanceolate leaves with a purplish marking. Since it produces thousands of seeds in a growing season, it can spread quickly. 

Hand-pulling and hoeing can help control the weeds in most landscapes. Mulching in garden beds can also achieve long-term results as the weed requires light to germinate. 

A systemic herbicide like glyphosate can also control large Garden Spurge infestations.

22. Giant Sensitive Plant (Mimosa pigra)

• Local Name: Giant Sensitive Plant
• Family: Fabaceae
• Annual or Perennial: Perennial 

Mimosa pigra is a dense, thorny shrub with sensitive leaves and pink flowers. It invades rivers, swamps, wetlands, and floodplains, especially in Kafue Flats and Lukanga areas, forming impenetrable thickets.

By choking these waterways, the weed not only displaces native vegetation but also affects birds such as cranes and other wildlife. 

The strategy commonly deployed by the local communities includes cutting, burning, and chemical control. Mimosa plants are slashed to ground level with the remaining fragments left to dry and later burned. 

The regrowth is treated with approved herbicides through foliar sprays, cut stump applications, and soil application. 

23. Flossflower (Ageratum houstonianum)

• Local Name: Flossflower, Goatweed, Ageratum, or Blue Billygoat Weed
• Family: Asteraceae
• Annual or Perennial: Annual or Short-lived Perennial 

Goatweed is an annual or short-lived perennial herb that grows 10-100 cm tall. The weed can be identified by its softly-haired, round stems, obovate to egg-shaped leaves with bluntly toothed margins, and clusters of purplish, blue, or pink fragrant, long-living, tubular flowers. 

Apart from wind dispersal, the seeds attach to animals, clothing, and contaminated produce, making it a highly invasive weed in pastures, crop fields, gardens, roadsides, waste areas, and disturbed sites. 

Hand-pulling is viable for small infestations. The plant parts need to be bagged and disposed of correctly to avoid resprouting.

Herbicides such as glyphosate and metsulfuron-methyl used with a surfactant are indicated for effective Flossflower control. 

24. Siam Weed (Chromolaena odorata)

• Local Name: Siam Weed or Jack in the Bush
• Family: Asteraceae
• Annual or Perennial: Perennial 

Siam Weed is a perennial subshrub that can grow up to 2.5-3m. It has a woody base, while the upper stems have soft, elliptic to triangular leaves, and panicles of white to pale pink flowers. 

Chromolaena odorata is an invasive weed of field crops, protected forests, and pastures. Siam Weed is highly allelopathic to neighbouring vegetation, toxic to cattle, and can cause allergic reactions to humans.

Pulling out by hand is effective if all the fragments are removed and disposed of away from the site. Repeated slashing and application of glyphosate or metsulfuron on the young shoots can assist in removing the weed.

25. Jungle Rice (Echinochloa colona)

• Local Name: Jungle Rice 
• Family: Poaceae
• Annual or Perennial: Annual 

Jungle Rice is a fast-growing annual grass that commonly invades margins of maize, rice, and vegetable farms and other disturbed muddy or swampy places. 

It is easily identified by its hairless stems and erect or ascending dull green culms, sometimes with purple banding.

Hand-pulling or hoeing before set seed will reduce the spread. Ensure that you dispose of it far from the fields and burn the weeds. Various herbicides like butachlor and glyphosate can be used to control Jungle Rice based on the areas of infestation.

Sylvia Kiragu

Lead Editor for Insight Weeds.

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The post 25 Most Common Weeds in Zambia (With Pictures) appeared first on InsightWeeds.

It is easily identified by its blue-green stems, soft bluish-green leaves, and a spike-like, narrow panicle with golden-yellow bristles. 

Zakat Grass Classification

• Domain: Eukaryota
• Kingdom: Plantae
• Phylum: Tracheophyta
• Subphylum: Angiospermae
• Class: Monocotyledonae
• Order: Poales
• Family: Poaceae
• Genus: Setaria
• Species: Setaria sphacelata
• Varieties: Setaria sphacelata var. Sphacelata, Setaria sphacelata var. Sericea, and Setaria sphacelata var. torta
• Common Names: Common Setaria, African Pigeon Grass, South African Pigeon Grass, Canary Seed Grass, Rhodesian Grass, Golden Bristlegrass, and Golden Setaria

Nativity and Distribution

Golden Millet is native to tropical and subtropical regions in Africa. These countries include Angola, Senegal, Botswana, Kenya, Tanzania, Namibia, and South Africa. 

The grass has since been naturalized in other regions globally, including Australia, the Americas, New Zealand, Hawaii, and Southeast Asia. 

Physical Characteristics

• Leaves: Glabrous, soft, bluish-green leaves
• Stems: Flattened blue-green stems
• Flowers: A spike-like, narrow panicle with golden-yellow bristles
• Roots: Fibrous root system

African Bristlegrass is a perennial, stout, densely tufted grass that can reach 2m tall. You can easily identify it by its blue-green stems, soft bluish-green leaves, and a spike-like, narrow panicle with golden-yellow bristles. 

The leaves are glabrous, soft, bluish-green, 10-50 cm long and 3-7mm wide, with entire margins and long pointed tips. The leaf sheath is also smooth and glabrous, but a line of hairs occurs where the blade meets the sheath. 

Stems are upright, flattened, hairless, and green, reaching 1.8-2 m in height. 

Zakat Grass produces an inflorescence consisting of a seedhead that appears spike-like, but it is actually a spiciform panicle, where several short branches are held towards the stem. 

The heads (7-50 cm long) bear clustered spikelets, typically in groups of one to four, subtended by golden-yellow bristles, each about 4-12 mm long. Spikelets are elliptic in shape, 1.5-3.5 mm long, and consist of a pair of glumes and two florets.

Reproduction, Dispersal, and Life Cycle

• Life Cycle: Perennial
• Seeds: It is a moderate seed-producing grass
• Climate: Tropical and subtropical climates
• Dispersal: Wind, water, birds, and contaminated produce

S. sphacelata is a perennial grass that thrives in tropical and subtropical climates. It can propagate by seeds but also produces short rhizomes.

The seeds are dispersed by wind, water, granivorous birds, and also as a contaminant of produce. Due to its high demand as a pasture and forage grass, it is also heavily propagated by seed and vegetative means. Zakat grass begins to grow in spring and continues to persist well into late autumn.

It thrives in a variety of soils, including sandy, stony, and loam soils. However, it prefers fertile, well-drained, and moist soil and can therefore tolerate flooding and waterlogging. 

It is not well adapted for alkaline, saline, or acidic soils and has low drought tolerance. Several cultivars have been developed that can withstand diverse soil conditions and weather phenomena like cold or frost. The well-known Setaria sphacelata cultivars are Nandi, Narok, and Kazungula.

Apart from desired pastures, Golden Millet is also found in riparian areas, parks, grasslands, roadsides, disturbed sites, and waste areas. 

Similar Plants

• Setaria pumila
• Setaria incrassata
• Pennisetum purpureum

Uses

1. It is an important fodder, hay, silage, and pasture grass in Africa.
2. It is a popular grass for cut-and-carry systems. 
3. The grass is used for soil stabilization and conservation along waterways.
4. It is used in crop rotation in mixed farming systems.
5. Grains are a famine food for humans and an important food source for birds.

Impact on Farms and Environment

Setaria sphacelata is a vital pasture grass in many regions globally. However, when introduced without careful management, it can become aggressively weedy. 

In cropping systems, for instance, it can spread in unwanted areas, competing for important nutrients and interfering with harvesting. 

Where it is grown as pasture grass, it can outcompete native grasses and other desirable pasture grasses. This can affect livestock nutrition, especially in the later growth stages where its crude protein steadily declines. 

Some cultivars also tend to have high levels of oxalates that can affect the palatability and digestibility for grazing animals. 

In non-agricultural areas, Zakat Grass can colonise disturbed areas such as roadsides and other disturbed sites, forming dense cover that can impede movement and potentially displace native plant species.

While it has not been declared a noxious weed, it is considered to be a significant weed in three Australian states, namely, Western Australia, Queensland, and New South Wales.

Control

• Cultural control: Revegetation and Competition
• Chemical control: Herbicides like haloxyfop and glyphosate

Removing African Bristlegrass using common methods like hand-pulling, mowing, intensive grazing, or prescribed burning may only provide temporary control or encourage further growth. 

However, deep cutting the grass and restoring native or more competitive grass species can offer effective and long-term control.

For even better results, consider applying herbicides indicated for perennial grass control, like haloxyfop and glyphosate. For any herbicide you decide to use, ensure to follow all the application directions.

Sylvia Kiragu

Lead Editor for Insight Weeds.

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The post Setaria sphacelata (Zakat Grass, Golden Millet, African Bristlegrass) appeared first on InsightWeeds.

They are mostly perennial grasses with erect, decumbent, or slightly spreading culms, bright green leaves, and deep and extensive root systems.

Brachiaria spp. Classification

• Domain: Eukaryota
• Kingdom: Plantae
• Phylum: Tracheophyta
• Subphylum: Angiospermae
• Class: Monocotyledonae
• Order: Poales
• Family: Poaceae
• Genus: Brachiaria
• Common Species: Brachiaria brizantha, Brachiaria decumbens, Brachiaria  ruziziensis, and  Brachiaria mutica

Nativity and Distribution

Palisade Grass is native to East and Central Africa. They have also been introduced in other tropical regions around the world, such as:

• Australia
• Asia
• South America
• South Pacific

Physical Characteristics

• Leaves: Broad or narrow, bright green leaves
• Fruits: Spikelets arranged along racemes
• Stems: Erect, decumbent, or slightly spreading
• Flowers: A panicle consisting of racemes
• Roots: Fibrous root system

The Brachiaria are a common savannah grass with about a hundred recorded species across the tropics. The most common grasses in this species include B. mutica (Para Grass), B. brizantha (Signal or Palisade Grass), and B. ruziziensis (Congo Grass). 

Leaves can be broad or narrow and smooth or hairy, depending on the species, but are typically bright green in color. The young leaves are usually softer but get coarse in maturity. 

Culms are erect, decumbent, or spreading, and some species, like B. brizantha have short rhizomes for propagation. 

The inflorescence is a panicle of racemes about 5-20 cm long. Spikelets are arranged in a panicle and vary in size. The flowering period is triggered by climatic cues in its growing range.

The caryopsis is small, lightweight, and typically ovoid, 2-5 mm long and 1-4 mm wide. 

Reproduction, Dispersal, and Life Cycle

• Life Cycle: Perennial 
• Seeds: Seed production varies per species
• Climate: Tropical and subtropical climates
• Dispersal: Wind and water

Most Brachiaria grasses behave as perennials, although some may occur as annuals in harsh conditions. Seed production is typically low, but they can remain dormant and viable for many years. 

The few seeds that are produced may have hairy bristles or spiky glumes that enable them to move short distances by water, wind, and human activity. 

However, some Bracharia commercial species like the Mulatto II and Cayman are bred for seed production in countries like Laos, Thailand, and Mexico.

Many of these grass species are valuable for forage, silage, and hay production and hence mainly propagated through vegetative cuttings. 

Once planted, the grass steadily germinates and spreads over several seasons. However, flush growth can occur during the rainy seasons, with some of the grasses (which have tolerance for drought) retaining their green leaves in the dry seasons. 

Semanhyia and other indigenous Brachiaria grasses grow best in warm tropics, requiring moderate to high rainfall. They are adapted to a range of soils, including low-nutrient and acidic soils. 

Most species thrive in full sunlight, and only a few can tolerate partial shade. Shade, including under trees, decreases biomass, leaf to stem ratio, and slows their overall growth. Brachiaria grasses are sensitive to frost, but rootstocks and crowns can survive light frost in some species, like B. brizantha. 

Uses

1. Brachiaria spp. is primarily used for livestock-feeding, including grazing, cut and carry, hay, and silage. The most preferred grasses are B. brizantha, B. ruziziensis, and B. decumbens, for their high biomass and good nutritional value, especially in the growing seasons. 
2. They are an important species for commercial hybrid breeding to produce cultivars for high seed yield and overcoming limitations like drought, shade, and low soil fertility. 
3. The grasses are used for soil conservation, erosion control, and weed suppression because of their good ground cover. 
4. They are used in intercropping, border plants in pest management systems, and agroforestry. 
5. It supports grazing wildlife in savannah grasslands. 

Impact on Farms and Environment

Brachiaria spp. can increase livestock productivity through quality fodder; in places where they are unwanted, they can become invasive, outcompeting local grasses. Additionally, due to its long-term seed dormancy, it may be difficult to eradicate the grass weed completely.  

Due to their rapid growth, in areas where they are used in intercropping, they can reduce crop yields. B. Brizantha, for instance, has been reported to reduce the rice yields by 40-50%. 

These grasses are also hosts to pests and diseases, putting crops at risk of diseases, which can lead to low yield or loss of the cover grass itself.

Control 

• Cultural control: Grazing and controlled burning
• Mechanical control: Mowing and repeated cutting to exhaust reserves
• Chemical control: Herbicides like atrazine, fluaziflop-butyl, and glyphosate

Heavy grazing can reduce biomass, but it must be supervised to minimize erosion or lead to the emergence of other weeds in the open areas. Controlled burning will only remove the top growth and requires other control measures to kill the underground parts.

Repeated cutting and mowing can exhaust reserves, leading to reduced cover. This measure may take time and requires patience. Ensure to remove the young plants before they flower or set seed. 

Herbicides indicated for Brachiaria spp. removal includes atrazine, fluaziflop-butyl, and glyphosate, depending on the area of infestation. For the best results, apply when the plants are young and actively growing. 

If you’re unsure of what herbicide to use for your farm or landscape, we recommend consulting a local extension officer.

Sylvia Kiragu

Lead Editor for Insight Weeds.

insightweeds.com/

The post Brachiaria spp. (Semanhyia, Palisade Grass) appeared first on InsightWeeds.

You can identify Pearl Grass by its flat or folded, shiny, green to light green foliage and fairly low, dense mats.

Pearl Grass Classification

• Domain: Eukaryota
• Kingdom: Plantae
• Phylum: Tracheophyta
• Subphylum: Angiospermae
• Class: Monocotyledonae
• Order: Poales
• Family: Poaceae
• Genus: Axonopus
• Species: Axonopus compressus
• Common Names: Carpet Grass, Broadleaved Carpetgrass, Tropical Carpet Grass, Blanket Grass, American Carpet Grass, Taiwan Grass, Taipei Grass, and Thai Grass

Nativity and Distribution

Pearl Grass is native to Mexico and South American countries like Brazil, Argentina, Belize, Colombia, Ecuador, and Venezuela. 

It has since been introduced in other regions, including North America, the Caribbean, Central America, Africa, Asia, Australia, and the Pacific Islands.

Physical Characteristics

• Leaves: Broadly oblong, blunt, shiny, light green to green 
• Fruits: Ovoid or lanceloid, about 2-3.5 mm long spikelets
• Stems: Slender, low-growing, about 15 cm, flowering culms 30-60 cm tall
• Flowers: A panicle comprising 2-3 spike-like racemes
• Roots: Fibrous root system

Pearl Grass is a creeping, stoloniferous grass that grows not more than 15 cm tall. It is commonly known as Carpet Grass.

It is easily identifiable by its dense, ground-hugging foliage and light green to green, flat or folded, and shiny leaves.

The sheath is loose, strongly compressed, and keeled, and often glabrous or with some hair on the outer margin. The leaves are broadly oblong, flat or folded, 2-16 cm long and 4-18 mm wide. 

They may be glabrous or hairy on the upper surface, with fine hairs on the margins with fine hairs, and acute to obtuse tips. The young grass leaves are light green and turn green in maturity. 

Stems are creeping, typically growing to 15 cm tall. However, when flowering, the culms grow erect to a height of about 30-60 cm tall. The nodes on culms are flattened, glabrous, or pubescent. 

Inflorescence is a panicle consisting of slender, 2-3, spike-like racemes. The spikelets are solitary, sessile, lanceolate, and about 2-3.5 mm long and 1-1.2 mm wide. Flowering timelines vary based on the environment, but typically occur throughout the growing season.

The seed is elliptical, obtuse, 1-5 mm long, and yellow-brown in color. 

Reproduction, Dispersal, and Life Cycle

• Life Cycle: Perennial 
• Seeds: It is a poor seed producer
• Climate: Tropical and subtropical climates
• Dispersal: Water, wind, animals, and contaminated soil

Axonopus compressus behaves as a perennial grass and thrives in tropical and subtropical climates. The grass can produce a few seeds that are often dispersed by water, wind, animals, or contaminated produce or machinery. 

However, it primarily spreads vegetatively by stolons (above-ground creeping stems), which root at the nodes and short underground rhizomes. This allows for rapid colonization of new areas or recovery after disturbance or grazing. 

The grass prefers shady areas and moderately drained sandy loam soils. That said, it can also grow well in light clay and acidic soils. It has low salinity tolerance and waterlogged or swampy conditions.

Similar Plants

• Axonopus fissifolius
• Paspalum conjugatum
• Chrysopogon aciculatus

Uses

1. The grass is used as a permanent pasture for grazing livestock due to its high grazing tolerance 
2. It is a popular turf grass for residential lawns, parks, and low-maintenance, non-elite sports fields.
3. It is planted as a soil cover in rubber, oil palm, and coffee plantations where shade is heavy to achieve weed suppression. 
4. The grass is used for soil stabilization and erosion control.

Impact on Farms and Environment

While Pearl Grass can provide good ground cover, maintain soil structure, and suppress weed growth, in some settings, it can become a troublesome weed itself. 

For instance, it can invade lawns, roadsides, and other disturbed sites, outcompeting desirable plants or turf. 

Since it has low nutritive value as it matures, it requires heavy grazing to keep it in its vegetative and nutritive stage. Otherwise, if left to dominate a pasture when mature, it can lead to reduced animal weight and eventual economic losses. 

Due to its efficient propagation and dense low-growth, it has the potential to shade out lower-growing plants, altering native biodiversity. 

Control

• Cultural control: Grazing and improving soil fertility
• Mechanical control: Pulling or tillage
• Chemical control: Herbicides like MSMA, bentazon, and metsulfuron-methyl

Frequent grazing can keep the grass short and prevent seed set, thereby reducing its vigor and spread. Frequent defoliation also limits stolon growth. 

Improving the nutrient status of a desired grass and reducing soil acidity can make Pearl Grass less competitive, gradually leading to its decline. Improving sun penetration can also provide the same effect since it thrives in shaded areas. 

Hand-pulling is only viable for small infestations and if all the nodes are removed. Repeated tillage can cut off the stolon network, reducing the grass cover. 

Herbicides indicated for Axonopus compressus removal include MSMA, DSMA, prodiamine, glufosinate, bromoxynil, glyphosate, and metsulfuron-methyl. Consult a local extension expert on the best herbicide for your area of concern.

Sylvia Kiragu

Lead Editor for Insight Weeds.

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The post Pearl Grass (Axonopus compressus) appeared first on InsightWeeds.

Apart from the known landscaping uses, the also play an important role in agriculture and the stability of numerous ecosystems. 

That said, distinguishing between the grasses can prove difficult for landscapers and farmers looking to plant or eradicate them.

In this post, we’ll explore different tropical grasses, their common names, distinct physical features, and pictures to help you learn more about them and for easier identification. 

1. Carpet Grass (Axonopus Compressus)

• Scientific Name: Axonopus Compressus
• English Name: Blanket Grass
• Annual or Perennial: Perennial 
• Grass, Sedge, or Broadleaf: Grass

Carpet Grass is a perennial stoloniferous grass that can reach 15 cm in height. It thrives in full sun or partial shade and wet to acidic soils. 

The leaves are opposite, oblong, smooth on both surfaces, and about 4-15cm long. Its unique stem culms are shallow-rooted and grow close to the ground, giving it a lush mat-formation.

This native American grass is commonly used as pasture or turf grass for its grazing tolerance and low-maintenance needs. 

2. Elephant Grass (Pennisetum purpureum)

• Scientific Name: Pennisetum purpureum
• English Name: Napier Grass
• Annual or Perennial: Perennial
• Grass, Sedge, or Broadleaf: Grass

Pennisetum purpureum is a vigorous grass that achieves an impressive height of 3-5m. It has broad, flat, and long leaves measuring 2 meters, robust stems that are covered with fine hairs, and well-developed roots.

Elephant Grass, also called Napier Grass, is one of the most versatile and high-yielding tropical grasses. It thrives in a variety of extreme conditions, including dry and wet environments, which can also make it an invasive weed in many ecosystems. 

Elephant grass is mainly grown for livestock feed, especially in cut-and-carry systems, due to its high biomass yield, for erosion control, and biofuel production.

3. Buffalo Grass (Paspalum conjugatum)

• Scientific Name: Paspalum conjugatum
• English Name: Carabao Grass
• Annual or Perennial: Perennial 
• Grass, Sedge, or Broadleaf: Grass

Buffalo Grass is a tropical perennial grass that is native to tropical and subtropical Americas. It produces short culms about 60 cm high, short and soft-textured leaves with a distinct midrib.

Buffalo Grass reproduces by seeds and vegetative means, making it a high-yielding turf. It can tolerate waterlogging and shade, and is commonly found in pastures, open areas, vineyards, irrigation channels, and forest clearings. 

The grass is popular in landscaping due to its high mowing and traffic tolerance. It is also grown for fodder in cut-and-carry systems, as ground cover in shaded areas, and for weed control. 

4. Bermuda Grass (Cynodon dactylon)

• Scientific Name: Cynodon dactylon
• English Name: Couch Grass
• Annual or Perennial: Perennial 
• Grass, Sedge, or Broadleaf: Grass

Bermuda Grass is a rapidly growing tropical grass that springs up in the warmer seasons. The African native grass has unique green to dark-green, bladelike leaves that can grow up to 5 cm long. 

You can also recognize its flattened, purplish, slightly hairy stems and deep rhizomes that typically penetrate 40-50 cm into the soil. It thrives in full sun, is drought-tolerant, and can also withstand high traffic. 

For these reasons, it is a popular turf grass in residential areas, golf courses, and gardens. It is also used in soil erosion control and as feed for livestock. 

5. Kikuyu Grass (Cenchrus clandestinus)

• Scientific Name: Cenchrus clandestinus
• English Name: Kikuyu Grass
• Annual or Perennial: Perennial 
• Grass, Sedge, or Broadleaf: Grass

Kikuyu Grass, previously classified as Pennisetum clandestinum, is a perennial tropical grass native to East Africa, and can be identified by its flattened, coarsely-textured leaves, heavily branched stolons, and dense foliage.

It thrives in sunny and warm climates and rapidly grows through rhizomes and stolons. Kikuyu Grass is a valuable pasture grass due to its high grazing tolerance and is a common turfgrass for residential lawns and golf courses.

However, it is also an invasive weed in many regions globally, especially because of its high seed dormancy and rapid growth. It can climb, shade, or release toxins that inhibit the growth of other plant species.

6. Para Grass (Urochloa mutica)

• Scientific Name: Urochloa mutica 
• English Name: Scotch Grass
• Annual or Perennial: Perennial 
• Grass, Sedge, or Broadleaf: Grass

Para Grass is a creeping, fast-growing, semi-aquatic perennial grass that grows 2-5m tall. It is native to parts of the Middle East and Central Africa. 

The leaf blades are broad, sparsely or densely haired, and about 30 cm long. Stems are hairy and semi-prostrate and have distinct swollen nodes as well as green to purplish glumes. 

Scotch Grass mainly propagates by creeping stems that produce shoots and roots, spreading several meters along the ground. 

It is commonly grown as fodder for livestock, for soil erosion control, land reclamation, and as an ornamental grass for its lush appearance. 

7. Buffel Grass (Cenchrus ciliaris)

• Scientific Name: Cenchrus ciliaris
• English Name: Foxtail Buffalo Grass
• Annual or Perennial: Perennial 
• Grass, Sedge, or Broadleaf: Grass

Buffel Grass is a tussock-forming, perennial grass, native to tropical Africa, the Mediterranean, and Southern Asia. It produces erect or decumbent culms that can reach up to 2m tall. The leaves are linear, bluish-green, about 3-30 cm long. 

C. ciliaris also bears spike-like panicles 2-14 cm long, comprising spikelets surrounded by hairy bristles. It thrives in arid and semi-arid areas and will commonly be located in grasslands and open areas.

Buffel Grass is a highly valued pasture and forage grass in the tropics. It is also used for land reclamation and soil erosion control. 

Due to its deep root system (a rootstock that can penetrate 2m in the soil), the grass can spread extensively and outcompete native grasses. It has been declared a noxious weed in countries like Australia, the USA, and Mexico. 

8. Signal Grass (Brachiaria decumbens)

• Scientific Name: Brachiaria decumbens or Urochloa decumbens
• English Name: Signal Grass/Kenya Sheep Grass
• Annual or Perennial: Perennial
• Grass, Sedge, or Broadleaf: Grass

Signal Grass is a perennial tropical grass native to the Eastern and Central African highlands. It can be decumbent or erect, growing up to 60cm tall. 

The leaves are short, soft, and bright green, with bent tips. Stems give rise to rhizomes and stolons, which can root down as deep as 2m in the deep soil. It thrives in all soil types except heavy clay soils and can tolerate shade. 

The grass is mainly grown as a permanent pasture for beef grazing or fodder in cut-and-carry systems due to its high palatability and heavy grazing tolerance. Additionally, Signal Grass can also be used in soil erosion control efforts and weed suppression. 

9. Guinea Grass (Megathyrsus maximus)

9. Guinea Grass (Megathyrsus maximus)

• Scientific Name: Megathyrsus maximus
• English Name: Guinea Grass/Tanganyika Grass
• Annual or Perennial: Perennial 
• Grass, Sedge, or Broadleaf: Grass

Guinea Grass is a large tufted grass that can grow between 50 and 350 cm tall, depending on the prevailing conditions. It is native to tropical Africa and Yemen. 

M. maximus produces blade-shaped leaves that can be up to 100 cm long, cylindrical, erect culms, a panicle 15-50 cm long with green to purple spikelets, and a short creeping rootstock.

The fast-growing grass is mainly grown for pasture, silage, and hay and is also used for soil erosion control. 

Due to its rapid growth and space uptake, it can become weedy in some regions, outcompeting native plant species in grasslands and woodlands. It is also considered a fire hazard in wildfire-prone areas globally.

10. BahiaGrass (Paspalum notatum)

• Scientific Name: Paspalum notatum
• English Name: Bahiagrass/Common Bahia
• Annual or Perennial: Perennial
• Grass, Sedge, or Broadleaf: Grass

Bahiagrass is a perennial warm-season grass, native to Mexico and South America. You can identify it by its flat, light-green, coarse-textured foliage and V-shaped inflorescence, comprising two racemes. 

It also produces low-growing stolons that are pressed to the ground and root at the internodes, forming dense mats. The stems can grow between 20 and 70 cm tall.

P. notatum thrives in sandy loam soils and full sun but can tolerate shade, saline conditions, and drought. It is primarily established as forage for grazing animals and soil erosion control.

Sylvia Kiragu

Lead Editor for Insight Weeds.

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The post Tropical Grasses With Their Names, Characteristics, and Pictures appeared first on InsightWeeds.

You can easily identify it by its coarse, pale green leaf blades with prominent midveins and pointed tips, liguleless collar, red-tinged stems, and a bushy, branched panicle. 

Barnyard Grass Classification

• Domain: Eukaryota
• Kingdom: Plantae
• Phylum: Tracheophyta
• Subphylum: Angiospermae
• Class: Monocotyledonae
• Order: Poales
• Family: Poaceae
• Genus: Echinochloa
• Species: Echinochloa crus-galli
• Common Names: Cockspur Grass, Barnyard Millet, Water Grass, Panic Grass, and Japanese Millet

Nativity and Distribution

Barnyard Grass is native to Asia and Europe. It has since been introduced in other regions, including: 

• Southern Canada
• United States
• Northern Mexico

Physical Characteristics

• Leaves: Flat, rolled in a bud with a sharp point, about 2-6 inches long
• Fruits: Spikelets, 3-4 mm long, densely arranged on branches
• Stems: Upright or sprawling and branching at the base 
• Flowers: Densely clustered, knot-like flowers, 6-25 cm long
• Roots: Fibrous root system

Barnyard Grass is a warm-season grass that can grow up to 1.5m tall. It is identifiable by its coarse, pale green leaf blades with prominent midveins and pointed tips, liguleless collar, red-tinged stems, and a bushy, branched panicle. 

Leaves are flat, broad, and elongate, 30-50 cm long and 1-2 cm wide. You can identify this annual from other warm-season grasses by its coarse texture, pale green colour, and lack of ligule in the junction between the leaf blade and the sheath.

Culms are upright or sprawling, round to flattened in cross section, and branching at the base, growing about 0.8-1.5m tall. They are rather thick, hairless, and have a reddish tinge at the base. 

The spikelets are oval, often long-awned, and measure approximately 3-4 mm in length. They are densely arranged in panicles, pale green to dull purple in colour, and contain florets with seeds. Flowering occurs between July and September.

The seed is ovate, shiny, with a pointed tip, about 1-2mm long, and tan to brown in colour.

Reproduction, Dispersal, and Life Cycle

• Life Cycle: Annual
• Seeds: A single plant can produce 40,000 seeds
• Climate: Temperate and tropical climates
• Dispersal: Animals, water, birds, machinery and as a seed contaminant

Cockspur Grass behaves as an annual, thriving in temperate and tropical climates. This grass propagates by seed, with each plant producing approximately 40,000 seeds per year.

The seeds are thought to be mainly dispersed as a contaminant in grains. Other dispersal methods include water, animals, birds, transfer of soil, and contaminated machinery and shoes. 

Barnyard Grass is adapted to a variety of soils, including wet soils and diverse sunny areas. It can tolerate moderate drought and partial shade. Seed germination begins in spring, and vegetative growth continues well into summer.

Seeding begins in July, and by early fall, it begins to turn brown. Later in the season, the grass dies off due to frost. When favorable conditions return in spring, the seeds produced in late summer and early fall give rise to new plants.

You’re likely to find Barnyard grass in utility lawns, pastures, cropping systems, ditches, and other disturbed sites.

Similar Plants

• Echinochloa colona
• Echinochloa oryzicola
• Sorghum halepense
• Panicum dichotomiflorum

Uses

1. It is used as cattle fodder and also cut for hay. 
2. The grass is used for land reclamation in saline and alkaline regions in Egypt.
3. It is an important food source for wild animals like deer and rabbits.
4. Young shoots and grain are consumed in times of scarcity.
5. A boiled concoction of the grass roots is used to treat indigestion in the Philippines.
6. Barnyard grass is used as a traditional remedy for spleen problems, sores, hemorrhages, and wounds.
7. The seeds are commonly mixed with rice grains to make rice pudding in India.
8. It is consumed in South Korea to assist in lowering cholesterol and blood sugar. 

Impact on Farms and Environment

Echinochloa crus-galli is considered one of the world’s worst weeds in cropping systems. It invades maize, sugarcane, and vegetables, aggressively competing for space, light, and important nutrients. 

The grass often outcompetes the crops by extracting up to 80% of the nitrogen in the soil, leading to poor yields and, in some cases, catastrophic plant failure. 

In paddy fields, it competes for water, heavily affecting moisture-sensitive crops. Rice yield losses in some regions can range from 20% to over 80%, depending on weed density and duration of infestation.

Barnyard Grass is susceptible to brown spot disease and is also host to aphids, parasites, and nematodes that can spread diseases, further increasing crop losses. 

What makes E. crus-galli even more challenging in farms is its propensity to produce many seeds, making it a persistent weed from season to season. 

Additionally, due to its ability to entangle with other crops and its similarity to the desirable plants, it can make harvesting difficult. The presence of the weed in harvested grain also reduces the quality and overall market value. 

Farmers dealing with a Barnyard Grass infestation incur high manual weed control costs, as using herbicides may not always be a viable option.

When it comes to landscaping, it is not as common as other annuals like crabgrass but, where present, it can reduce the aesthetics of cool-season turf as it progressively turns brown. 

In the environment, the grass forms dense growths that choke out native plants in wetlands, riparian zones, and disturbed habitats, reducing local biodiversity. Where it becomes difficult to control, it can alter the structure of ecosystems, including rice paddies and wetland margins, affecting aquatic life and bird populations.

Control

• Cultural control: Maintain a healthy lawn and solarization
• Mechanical control: Hand-pulling, digging, or mowing
• Chemical control: Herbicides like prodiamine, pendimethalin, tropemazone, and quinclorac

Maintaining a healthy lawn through proper management practices provides easy and effective control against Barnyard Grass. Where few grass plants are present, hand-pulling or using a trowel can also prove effective.

For larger infestations, mowing the lawn below 3 inches will discourage leaf and seedhead formation, hence reducing weed density.

In crop farms, options like a 40-day solarization, rotation with forage crops or winter grains, frequent cultivation, and early-season mulching can discourage or suppress growth.

Preemergence herbicides indicated for Barnyard Grass control include prodiamine, s-metachlor, EPTC, and pendimethalin.

The most effective postemergence herbicides are quinclorac, fenoxaprop-p-ethyl, nicosulfuron, foramsulfuron, and topramezone, which are selective, or glyphosate, a systemic and non-selective herbicide. 

Ensure to read the label and follow the application directions based on the area or crop affected when using any of the herbicides.

Sylvia Kiragu

Lead Editor for Insight Weeds.

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The post Barnyard Grass (Echinochloa crus-galli) appeared first on InsightWeeds.

You can easily identify the grass by its erect or ascending culms, alternate, tapering leaves, and hairy to minutely hairy leaf sheaths. 

Signal Grass Classification

• Domain: Eukaryota
• Kingdom: Plantae
• Phylum: Tracheophyta
• Subphylum: Angiospermae
• Class: Monocotyledonae
• Order: Poales
• Family: Poaceae
• Genus: Urochloa
• Species: Urochloa trichopus
• Common Names: Common Signal Grass or Bushveld Signal Grass

Nativity and Distribution

Signal grass is native to tropical and southern parts of Africa, subtropical Asia, western Madagascar, and the Arabian Peninsula in countries like:

• Angola
• Congo
• Ethiopia
• Kenya
• South Africa
• Zimbabwe
• Zambia
• India
• China
• Saudi Arabia
• Yemen

Physical Characteristics

• Leaves: Alternate, linear, leaves tapering to a long point
• Fruits: Strongly flattened caryopsis
• Stems: Erect or ascending culms that can reach up to 1.5m 
• Flowers: Panicle comprising 3-20 racemes on a narrow axis 
• Roots: Fibrous root system

Urochloa trichopus is a clump-forming or tufted grass that sometimes shows stoloniferous tendencies and grows between 20 and 150 cm tall. 

It is easily identified by its erect or ascending culms, alternate, tapering leaves, and glabrous to minutely hairy leaf sheaths.

The leaves are alternately arranged, linear, tapering to a long point, about 5-30mm long and 5-20mm wide. The leaf sheath is glabrous to minutely hairy. Culms are erect to ascending, reaching up to 1.5m in favorable conditions. 

Signal grass produces a panicle consisting of 3-20 racemes borne along a central axis, about 20 cm long. Spikelets (2.5-5.5mm) are ovate, featuring a lower male stamen and upper bisexual florets. The seed is a strongly flattened caryopsis.  

Reproduction, Dispersal, and Life Cycle

• Life Cycle: Annual 
• Seeds: It is a prolific seed producer
• Climate: Tropical and subtropical climates
• Dispersal: Wind and water

Signal grass behaves as an annual, thriving in the tropical and subtropical climates. It produces many seeds with high viability. The seeds are small and light, easily dispersed by wind and water.

The grass also reproduces by stolons, which root at the node. This propagation strategy typically occurs more in the native settings, while both stolons and seeding are used for other uses. However, freshly gathered seeds go through dormancy for 6-12 months.

The grass can thrive on a variety of soils, including fertile and moist sandy loam soil or clay loam soil, and will tolerate drought and heat. It also prefers full sun and will not tolerate cool temperatures.

Similar Plants

• Urochloa brizantha
• Urochloa decumbens
• Urochloa oligotricha

Uses

1. It is a good fodder plant in semi-arid areas. 
2. It is gathered as food in parts of Southern Africa, such as Botswana and Zimbabwe.

Impact on Farms and Environment

U. trichloa can offer valuable fodder in dry environments, enhancing livestock feeding strategies. It also supports food security in arid areas during scarcity, where seeds are consumed or ground as flour.

The grass grows in secluded habitats such as wooded and savanna grasslands and in semi-arid areas. Therefore, it is not a serious weed in cropping systems and gardens.

However, as a pioneer in disturbed environments, it may compete with native vegetation. Its high seed production and favorable conditions may allow it to displace other plants, but its invasive nature is not documented. 

Control 

• Cultural control: Grazing can limit the spread of the grass
• Mechanical control: Cutting, hand-pulling, and tilling

Since Signal grass is palatable, practicing strategic grazing can help keep the grass growth under control where it is considered to have overgrown. 

If it invades undesired areas, mechanical strategies like hand-pulling, cutting, and tillage before seed set can reduce reproduction.

Overall, an integrated management system combining rotational grazing, timely removal before flowering, and monitoring regrowth will provide the best control results.

Sylvia Kiragu

Lead Editor for Insight Weeds.

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The post Urochloa trichopus (Signal Grass) appeared first on InsightWeeds.

It is easily identified by its blue to green-blue leaves and stems, as well as its dark brown awns that twist together at seed maturity.

Spear Grass Classification

• Domain: Eukaryota
• Kingdom: Plantae
• Phylum: Spermatophyta
• Subphylum: Angiospermae
• Class: Monocotyledonae
• Order: Cyperales
• Family: Poaceae
• Genus: Heteropogon
• Species: Heteropogon contortus
• Common Names: Speargrass, Common spear grass, Black spear grass, Bunch spear grass, Tangle grass, Tanglehead, and Twisted beardgrass. 

Nativity and Distribution

Spear grass is native to Africa, Southern Asia, Australia, Oceania, and Southwestern Europe. Today, it is naturalized in other regions globally such as:

• Southern United States
• Central and Southern America
• East Asia
• Caribbean

Physical Characteristics

• Leaves: Flat or folded, green to bluish-green, 10-30 cm long x 2-8 mm wide
• Stems: Slender, tufted, up to 1.5 m tall
• Flowers: Long raceme borne with a single or pair of flat green spikelets
• Roots: Fibrous root system

Heteropogon contortus is a perennial tufted grass 0.5-1.5m tall. It reproduces by seeds and vegetative transplants.

The grass is easily identified by its blue to green-blue leaves and stems as well as its dark brown awns that twist together at seed maturity.

Culms are slender, typically geniculate at the base, erect at upper levels, and often branched, especially during flowering. The tufted stems are about 0.5-1.5m tall. 

Bluish to bluish-green in color, the leaves are either glabrous or with few fine hairs. The blades are folded when young and flat at maturity, about 3-30 cm long and 3-8mm wide. 

Spear grass produces a 3-8 cm raceme of narrowly cylindrical homogamous spikelets. The sterile spikelets are awnless and located at the base of the raceme. The bisexual spikelets are awned and borne at the apex. As the seeds mature, the long awns (6-10 cm) tips twist together, a distinct trait of the spear grass. 

The caryopsis is cylindrical, grooved, whitish, and 3.5-4.5 mm long.

Reproduction, Dispersal, and Life Cycle

• Life Cycle: Perennial 
• Seeds: A single plant can produce 3,000 seeds
• Climate: Tropical and subtropical climates
• Dispersal: Attachment to fur and clothing

H. contortus behaves as a perennial grass and thrives in tropical and subtropical climates with distinct wet and dry seasons. It has a lifespan of less than five years.

The grass is a prolific seed producer with a single plant producing up to 3,000 seeds. Their harpoon-like barbs aid them in attaching to animal fur, feathers, and clothing, dispersing them to new areas.

When the moisture conditions are right, the awns and sharp tips twist, planting the seeds in the soil. Germination occurs between 5-7 days. Seed dormancy is 6 months with a lower germination rate.

Similar Plants

• Chrysopogon fulvus
• Bothriochloa pertusa
• Sorghastrum nutans

Uses

1. It is used as a summer pasture and forage for livestock.
2. It is grown as an ornamental plant for its interesting seed head.
3. The grass is used for thatching, matting, and stuffing pad floors.
4. It is used to make remedies for burns and wounds by the Zulu community in South Africa.
5. The grass is used in land reclamation, weed suppression, soil erosion, and carbon sequestration efforts.

Impact on Farms and Environment

Heteropogon contortus is highly regarded for its land reclamation ecosystem restoration abilities. Tropical vegetable farmers in Hawaii rely on the grass for weed suppression, improving soil structure, and increasing biodiversity. 

The grass has also been recommended for soil erosion control along roadsides, construction sites, and other disturbed sites in the U.S. 

H. contortus can also improve biodiversity in various ecosystems, including riparian areas. For instance, it is a favorite pollinator plant for bees. 

However, spear grass has also been declared as an invasive weed in some regions in Asia and America. It is a common weed of crop farms, grasslands, pathways, and roadsides. Its ability to withstand burning and light to medium grazing can make eradication efforts difficult.

The seed’s harpoon-like attachments can become embedded in the wool and skin of sheep. This has led to the closure of some wool industries in parts of Australia, negatively impacting livelihoods.

It is also a collateral host for downy mildew in sorghum and maize. 

Control

• Cultural control: Heavy grazing can help eradicate the grass.
• Chemical control: Apply glyphosate herbicide for complete removal.

Spear grass is intolerant of continuous heavy grazing and this cultural practice can be used to eradicate it in the early wet season.

Glyphosate is highly recommended for lasting and more effective control against Heteropogon contortus.

Sylvia Kiragu

Lead Editor for Insight Weeds.

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The post Heteropogon contortus (Spear grass) appeared first on InsightWeeds.

It is easily identified by its yellow-green color, boat-shaped leaf tips, and a distinct whitish flower head.

Poa annua Classification

• Domain: Eukaryota
• Kingdom: Plantae
• Phylum: Spermatophyta
• Subphylum: Angiospermae
• Class: Monocotyledonae
• Order: Poales
• Family: Poaceae
• Genus: Poa
• Species: Poa annua
• Varieties: Poa annua var. Annua and Poa annua var. reptans
• Common Names: Poa, Annual blue, Annual Meadow grass, Meadow grass, and Dwarf meadow grass

Nativity and Distribution

Annual bluegrass is native to Temperate Asia, Western Europe, and Northern Africa. Today it can be found in all ecosystems globally including:

• Australia
• Arctic
• Antarctica
• North America
• South America

Physical Characteristics 

• Leaves: Smooth, yellowish to dark green, boat-shaped blades
• Stems: Upright, clump-forming stems about 30 cm long
• Flowers: White, stalked, awnless, spikelets 1-2 cm
• Roots: Fibrous roots system

Poa annua is primarily a winter annual grass, although in some habitats it can survive into the second year as a biennial. 

It is easily identified by its clumping growth, smooth, yellowish to dark green leaves, and a distinct whitish flower head. 

The stems are upright, clump-forming, and bright green, growing up to 2.5-30.5 cm tall. They enlarge by tillering and can root at the lower nodes.

The leaves are flat, smooth, 1-14 cm long and 0.25 cm wide, and often have a yellowish-green color with linear margins. They are typically transversely wrinkled and abruptly blunt at the tips, giving them a characteristic bow-shaped appearance.

Meadow grass produces greenish-white seed heads with spikelets 1-2 cm long. The spikelets contain 3-8 flowers each and are loosely arranged on spreading branches. 

The seeds are long, elliptical, yellow-gray, about 0.25 cm long, and encased in a panicle.

Reproduction, Dispersal, and Life Cycle

• Life Cycle: Annual but can also be biennial
• Seeds: Each plant can produce over 2,000 seeds
• Climate: Cool, temperate climate
• Dispersal: Wind, water, animals, and contaminated seeds and vehicles

Annual bluegrass behaves as a short-lived winter annual but can also survive into the second year as a biennial. It typically thrives in cool temperate climates but is tolerant to a variety of soil conditions and hard frost, hence its existence in remote areas.

The grass is a prolific seed producer with a single plant producing between 1,000- 2,000 seeds. The seeds can remain dormant for many years in diverse ecosystems. 

Poa annua is the only non-flowering plant to grow and maintain a seed bank in harsh territories like the Arctic and Antarctica.

The seeds are dispersed by wind, water, and animals, through contaminated seeds and farming equipment. 

Similar Plants

• Poa compressa
• Poa pratensis
• Poa palustris

Uses

1. It can be grown as livestock fodder in extremely poor grasslands.
2. It is used as putting greens due to its high-traffic tolerance and low maintenance.

Impact on Farms and Environment

P. annua is considered an aggressive weed of various vegetables, cereals, and orchards in cooler climates. The grass itself has low competitive ability. However, due to its numerous seeds, it can rapidly colonize all available gaps in crop farms, causing poor plant management and harvesting difficulty.

Apart from competing for essential nutrients, the grass weed is also a host to cereal aphids and destructive weevils like the Sitobion avenae and Listronotus bonariensis respectively. These invasive insects often lead to poor crop yield and pasture quality and may require costly control measures to prevent large losses.

Annual meadow grass is a common and troublesome weed of lawns and turfgrass. To begin with, the grass is small in size and it is hardly noticeable as it grows along the desired turf. 

Due to its unique yellowish-green color, it can make most turfs look patchy. Additionally, since it’s an annual, its tendency to die off can leave big bare patches on the turf depending on the size of the infestation.

Apart from crop farms and lawns, Poa annua is also a weed of roadsides, gardens, and waste areas.

Control

• Cultural control: Maintain a healthy and dense turf that can outcompete the grass weed.
• Mechanical control: Hand-pull or dig is a viable option for young plants.
• Chemical control: Apply herbicides like dithiopyr and pendimethalin

Maintaining a healthy and dense lawn is one of the best strategies to keep a Poa encroachment away. Applying the required nitrogen fertilizer and avoiding overwatering are some of the lawn maintenance measures that can help keep your turf grass vigorous and healthy.

If the infestation is small or the plants are young, you can hand-pull or dig using a tool to get the clumping weeds from the roots. 

Poa annua is mainly controlled with preemergence herbicides like dithiopyr, oryzalin, and pendimethalin which are applied in mid-August to early September. However, it has been reported to become resistant to various herbicides like paraquat, glyphosate, and prodiamine when used for a long time. 

We recommend consulting a local expert to find the best herbicide for annual bluegrass in your farm, orchard, garden, or lawn.

Sylvia Kiragu

Lead Editor for Insight Weeds.

insightweeds.com/

The post Poa annua (Annual bluegrass) appeared first on InsightWeeds.

The grass is easily identifiable by its thick creeping stems and short green leaves that are flattened or upward-folding along the midrib.

Cenchrus clandestinus Classification

• Domain: Eukaryota
• Kingdom: Plantae
• Phylum: Spermatophyta
• Subphylum: Angiospermae
• Class: Monocotyledonae
• Order: Poales
• Family: Poaceae
• Genus: Cenchrus
• Species: Cenchrus clandestinus
• Common Names: Kikuyu grass, Kikuyu

Nativity and Distribution

Cenchrus clandestinus is native to the highlands in Eastern Africa in countries like Kenya, Uganda, Tanzania, and Burundi.

Currently Kikuyu grass is naturalized in many regions globally including:

• Asia
• Europe
• Australia
• South Africa
• North America
• South America

Physical Characteristics

• Leaves: Short, bright green blades, glabrous or soft hairy
• Stems: Jointed, long, thick creeping stems 
• Flowers: Inconspicuous narrow flower spikelets subtended by a ring of bristles
• Roots: Fibrous root system

Kikuyu grass is a low-growing perennial plant that can reach 30-90 cm in height. It is easily identified by its thick creeping stems and short bright green leaves that are flattened or upward folding along the midrib.

The grass has jointed thick stems (stolons) about 40 cm long that are heavily branched to form dense mats on the ground. It also produces creeping underground stems, also called rhizomes that run to a depth of 20-30 cm.  

The leaves comprise a base leaf sheath and a spreading leaf blade. Leaf blades are short, bright green, glabrous or soft hairy, about 1-30 cm and 3-7 mm wide. Kikuyu grass leaves are soft and folded in the initial growth, but become flatter and coarser as it matures.

C. clandestinus produces inconspicuous inflorescence which remains hidden within the sheath, with occasional protrusion of the style or stamen tips. It consists of 2-4 long and narrow flower spikelets about 10-20 mm long and 0.8-1.5 mm wide, with two florets subtended by a ring of bristles. 

Seeds are somewhat flattened, dark reddish brown, and about 2-3 mm long and 1.5 mm wide. 

Reproduction, Dispersal, and Life Cycle

• Life Cycle: Perennial 
• Seeds: Produces seeds under certain conditions
• Climate: Tropical and subtropical climates
• Dispersal: Animals, water, contaminated implements, crop seed, and vehicles

Cenchrus clandestinus behaves as a perennial plant that thrives in tropical and subtropical climates. It primarily propagates vegetatively through stolons and rhizomes. 

However, in areas where seed is set, it can be dispersed by animals, water, or contaminated vehicles, implements, and crop seed. 

Kikuyu grass is a desired turf for amenity and ornamental use and is, therefore, also deliberately introduced into new areas. 

Similar Plants

• Cenchrus villosum
• Paspalum distichum
• Paspalum vaginatum
• Digitaria abyssinica

Uses

1. It is a preferred turf for residential lawns and golf courses due to its attractive bright green foliage.
2. It is grown for livestock pasture.
3. The grass is used to stabilize soils on steep slopes and prevent soil erosion.
4. It is used in land reclamation efforts.
5. The grass is grown to suppress other invasive weeds like the senecio inaequidens.

Impact on Farms and Environment

C. clandestinus is a serious weed due to its elongate and highly invasive stems. While it is mostly grown for beneficial purposes, it can easily escape and colonize new areas, including farmlands. 

Its thick mat-like growth can affect cultivated crops, leading to poor yields and consequently, high economic losses. Apart from competing for essential nutrients, kikuyu grass is also reported to have an allelopathic effect on plants like lucerne, tomatoes, and herbs.

Kikuyu grass is also considered a noxious environmental weed as its creeping stems block irrigation channels, waterways, roadsides, and industrial infrastructure. It also invades natural habitats by climbing over other plants, suppressing the growth of native species. 

The aggressive grass also springs up on lawns, taking root over large areas if left unchecked. Since it’s resistant to mowing due to its extensive root system, it can be hard to eradicate, requiring intensive and expensive control mechanisms. 

While it considered a high-value pasture grass, when growing in highly-fertile conditions or infected by fungi, it can cause toxicity in livestock, such as sheep.

Control

• Cultural control: Grow competitive plants that can outcompete the grass.
• Chemical control: Apply selective or non-selective herbicides like oryzalin and glyphosate

Planting taller or groundcovering vegetation that can outcompete the grass can help reduce the encroachment. For instance, following a maize crop harvest, legume fallows are encouraged to control the grass infestations.

Maintaining a vigorous and healthy lawn is another effective strategy against 

Effective control can also be achieved through application of selective or non-selective chemical herbicides for perennial grasses. However, the application strategy depends on the type of area infested. 

The most recommended herbicides include glyphosate, fluazifop, oryzalin, prodiamine, or pendimethalin. 

Sylvia Kiragu

Lead Editor for Insight Weeds.

insightweeds.com/

The post Cenchrus clandestinus (Kikuyu grass) appeared first on InsightWeeds.