Sphaeranthus africanus: How to Spot and Control It in Rice
Sphaeranthus africanus is an upright broadleaf weed from the daisy family, with winged stems and small round flower heads. It grows in rainfed lowland rice fields in the Philippines. It has no listed local or English name, so this page uses its scientific name. Here you will learn how to spot it and how to control it in your palay.
What Is Sphaeranthus africanus?
Sphaeranthus africanus belongs to the Asteraceae, the daisy or sunflower family. It has no common local name and no English name, so most guides call it by its scientific name. It grows upright and branches out as it gets older. You will find it in rainfed lowland rice fields, where it comes up with the crop.
This weed is an annual. It sprouts, grows, flowers and dies within one season, and it spreads only by seed. Each round flower head holds a cluster of tiny flowers, and each one can make a seed. When those seeds drop, they stay in the soil and sprout with the next crop. So even a few missed plants can mean a weedier field next season.
| Name | Sphaeranthus africanus |
|---|---|
| Family | Asteraceae (Compositae) |
| Weed group | Broadleaves (see the three groups) |
| Local names | None recorded |
| Life cycle | Annual |
| Spreads by | Seeds |
| Where it grows | Rainfed lowland rice fields |
How to Identify Sphaeranthus africanus
Look for an upright plant with leafy wings running along its stems and branches. These wings make the stem look flat and broad. As a broadleaf, it has wide, flat leaves with netted veins, unlike grasses and sedges. The leaves are oval to oblong, wider near the tip, with finely toothed edges. At the top, it carries many small round heads packed with greenish white flowers.
- Upright plants with broad, leafy wings running down the stems and branches.
- Oval to oblong leaves, wider near the tip, with fine teeth along the edges.
- Many small, round flower heads at the ends of the branches.
- Tight clusters of greenish white flowers packed into each round head.
Why It Hurts Your Palay
Sphaeranthus africanus competes with your palay for light, water and fertilizer. It stands upright and branches out, so a thick stand can shade young rice between the rows. Rice suffers most early in the season, before its leaves close over the field.
As an annual that spreads only by seed, its biggest threat comes later. Plants that you miss will flower, and each round head can add seed to the soil. Its seeds can also mix with harvested palay and lower the quality of your grain. So the weeds you skip this season come back in larger numbers next season.
How to Control Sphaeranthus africanus
- Pull or cut plants before the round flower heads open, since every head that matures adds seed to your field.
- Weed early in the season, while the plants are small and easy to pull from the soil.
- Clean your tools and bunds after weeding, and do not leave flowering plants in the field to drop seed.
What to Do at Each Age of Your Rice
- 0 to 5 days: keep the soil saturated. Use a pre emergence herbicide only if the field had many weeds last season.
- 6 to 10 days: hand weed in transplanted rice. In direct seeded rice, this is the window for an early post emergence spray.
- 11 to 20 days: keep water in the field, weed by hand or with a rotary weeder, and let Azolla and the Altica beetle help. Spray only if those fail.
- 21 to 30 days: top up the water and keep weeding. Spray only if weeding fails.
- 31 to 40 days (transplanted rice): hand weed. A spray this late is only a rescue.
- After any post emergence spray, bring the water back within 1 to 3 days at 3 to 5 cm and hold it for 4 to 5 days. Keep young rice above it.
Active Ingredients That Work on Broadleaves
If water and weeding cannot hold Sphaeranthus africanus down, choose an active ingredient that works on broadleaves at the age of your rice. Each active ingredient in it is in a herbicide registered in the Philippines for rice. Shop by the ingredient on the label, never by the brand. If your field also has other kinds of weeds, the weed control helper in anee.io finds the ingredients that cover all of them.
| Rice age (days after planting) | Transplanted rice (lipat tanim) | Direct seeded rice (sabog tanim) |
|---|---|---|
| 0 to 5 days | Pretilachlor, Oxadiazon, Butachlor plus 2,4 D IBE, Pyrazosulfuron ethyl plus pretilachlor, Imazosulfuron, Penoxsulam plus butachlor, Tefuryltrione plus triafamone, Thiobencarb plus 2,4 D IBE | Pretilachlor, Oxadiazon, Pretilachlor plus butachlor, Butachlor plus 2,4 D IBE, Pendimethalin, Pyrazosulfuron ethyl plus pretilachlor, Butachlor with safener |
| 6 to 10 days | Butachlor plus propanil, Cyhalofop butyl plus bispyribac sodium, Bispyribac sodium, Penoxsulam plus cyhalofop butyl, Pendimethalin, Cyhalofop butyl plus propanil, Imazosulfuron, Propyrisulfuron, Clomazone plus propanil, Thiobencarb plus propanil, Flucetosulfuron, Cyhalofop butyl plus florpyrauxifen benzyl | Butachlor plus propanil, Cyhalofop butyl plus bispyribac sodium, Bispyribac sodium, Pyribenzoxim plus cyhalofop butyl, Penoxsulam plus cyhalofop butyl, Cyhalofop butyl plus propanil, Pyrazosulfuron ethyl plus pretilachlor, Pendimethalin, Propyrisulfuron, Clomazone plus propanil, Thiobencarb plus propanil, Pretilachlor plus pyribenzoxim, Penoxsulam, Flucetosulfuron, Cyhalofop butyl plus florpyrauxifen benzyl |
| 11 to 20 days | Cyhalofop butyl plus bispyribac sodium, Bispyribac sodium, Pyribenzoxim plus cyhalofop butyl, Penoxsulam plus cyhalofop butyl, Metamifop plus bispyribac sodium, Bentazone, Cyhalofop butyl plus ethoxysulfuron, Propyrisulfuron, Fenoxaprop P ethyl plus ethoxysulfuron, Flucetosulfuron, Carfentrazone ethyl, Florpyrauxifen benzyl, Cyhalofop butyl plus florpyrauxifen benzyl | Cyhalofop butyl plus bispyribac sodium, Bispyribac sodium, Pyribenzoxim plus cyhalofop butyl, Penoxsulam plus cyhalofop butyl, Metamifop plus bispyribac sodium, Bentazone, Pyribenzoxim, Cyhalofop butyl plus ethoxysulfuron, Propyrisulfuron, Fenoxaprop P ethyl plus ethoxysulfuron, Flucetosulfuron, Carfentrazone ethyl, Florpyrauxifen benzyl, Cyhalofop butyl plus florpyrauxifen benzyl |
| 21 to 30 days | 2,4 D amine, 2,4 D IBE, MCPA, Metamifop plus bispyribac sodium, Bentazone, Metsulfuron methyl plus chlorimuron ethyl, Fenoxaprop P ethyl plus ethoxysulfuron, Carfentrazone ethyl | 2,4 D amine, 2,4 D IBE, Cyhalofop butyl plus bispyribac sodium, Pyribenzoxim plus cyhalofop butyl, MCPA, Metamifop plus bispyribac sodium, Bentazone, Metsulfuron methyl plus chlorimuron ethyl, Pyribenzoxim, Carfentrazone ethyl |
| 31 to 40 days | Metsulfuron methyl plus chlorimuron ethyl | Not listed for direct seeded rice |
Spray Safely
Use only herbicides registered with the Fertilizer and Pesticide Authority, and follow the label on the pack: the rate, the timing, the water and the protective clothing. Switch herbicide groups between seasons so the weeds do not learn to survive them. Our guide to herbicides for rice explains the groups.
Keep Sphaeranthus africanus Out Next Season
- Plant clean, certified seed. Weed seeds mixed into the punla are the easiest way in.
- Keep the seedbed, the canals and the bunds free of weeds, so seed does not wash or blow into the paddy.
- Prepare the land well: flood, plow, let the weed seeds sprout, then kill them when you harrow. Level the field so water covers it evenly.
- Pull escapes before they flower and set seed, and carry them out of the paddy instead of leaving them on the bund.
- Keep the field clean after harvest and through the fallow, so fewer seeds build up in the soil for next season.
These steps work for every broadleaf weed in the paddy, not only this one. The weed management guide puts them in order for a whole season.
Not Sure It Is Sphaeranthus africanus?
Take a clear photo of the leaf, the stem and the flower or seed head, then ask Anee, the smart farm technician in anee.io, in Tagalog or English. Anee tells you which weed it most likely is, its group, and what to do at the age of your rice. You can also put the weeding days on your cropping calendar, so the team knows when to go in.
anee.io keeps your weeding, spraying and water on one calendar, and Anee answers when a plant looks wrong.
- Weeding days on the season calendar
- Photos and notes for every lot
- Anee, the smart farm technician, in Tagalog or English
Questions Farmers Ask About Sphaeranthus africanus
What is Sphaeranthus africanus commonly called?
How do I control this weed in my rice field?
Why does this weed keep coming back each season?
Get Sphaeranthus africanus out of your field
With Libre + Anee, read the whole guide: how to tell it from your crop, and what to do and spray at every age of your crop.
The account is free, no credit card.
