Smallflower Umbrella Sedge: How to Spot and Stop It in Rice Fields
Smallflower umbrella sedge is a fast growing annual sedge of irrigated and rainfed lowland rice fields in the Philippines. Its scientific name is Cyperus difformis, and farmers know it as payong payong, ubod ubod and other names. This page shows how to spot it, how much harm it does, and how to control it early.
What Is Smallflower Umbrella Sedge?
This damo is a sedge from the Cyperaceae family. Farmers around the country know it by many names, such as baong baong, bulo butones, payong payong, siraw siraw, treskantos, tuhog dalang and ubod ubod. From afar it can look grassy, but it is not a grass at all.
You will find smallflower umbrella sedge in both irrigated and rainfed lowland rice fields. It is an annual that spreads by seed only, but it makes up for that with speed. In fact, it can finish its whole life cycle within 30 days. So it can flower and drop seed long before your palay is ready for harvest. It also does best in fields where the water level keeps going up and down. That is why steady water and early weeding matter so much with this weed.
| Name | Smallflower umbrella sedge |
|---|---|
| Scientific name | Cyperus difformis |
| Family | Cyperaceae |
| Weed group | Sedges (see the three groups) |
| Local names | Baong baong, bulo butones, payong payong, siraw siraw, treskantos, tuhog dalang, ubod ubod |
| Life cycle | Annual |
| Spreads by | Seeds |
| Where it grows | Irrigated and rainfed lowland rice fields |
How to Identify Smallflower Umbrella Sedge
Like all sedges, it has a solid stem with no nodes. Near the top, the pale green stem is sharply three angled, so you can feel clear edges when you roll it between your fingers. Its leaves stay shorter than the stem, and the plant can grow as tall as 75 cm. At the tip it carries a simple or branched umbrella of round heads packed with many tiny spikelets.
- Pale green stems with three sharp edges near the top, easy to feel by hand.
- Leaves shorter than the stem, so the flower heads stand clear above them.
- An umbrella shaped flower head, simple or branched, at the tip of each stem.
- Round balls of tightly packed spikelets, like tiny buttons on short stalks.
- Plants flowering while still young, since it can finish its life in 30 days.
- Patches that spread fast where the field dries out and floods again by turns.
Why It Hurts Your Palay
Smallflower umbrella sedge is a C3 weed and a heavy seed maker. One plant can produce 50,000 seeds, and 60 percent of them can germinate. It can also complete its whole life cycle within 30 days. In a ricefield where the moisture level keeps changing, it spreads fast and can become the main weed.
If you leave it uncontrolled, it can reduce rice yield by as much as 43 percent. Besides that loss, its seeds can mix with harvested palay and lower the quality of seed you keep. Thick patches can also shelter insect pests near the rice hills.
How to Control Smallflower Umbrella Sedge
- Keep a steady water level in the field, because this sedge takes over where the soil keeps drying and flooding by turns.
- Weed early and check again soon after, since it can complete its life cycle and drop seed within 30 days.
- Level the field well during land preparation, so no high spots stay dry and give its seeds a place to sprout.
- Pull plants before the round heads ripen, because one plant can produce 50,000 seeds.
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 Sedges
If water and weeding cannot hold smallflower umbrella sedge down, choose an active ingredient that works on sedges 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 | Butachlor, 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 | Butachlor, Pretilachlor, Oxadiazon, Pretilachlor plus butachlor, Butachlor plus 2,4 D IBE, 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, 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, Pyrazosulfuron ethyl plus pretilachlor, 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 Smallflower Umbrella Sedge 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 their flower clusters turn brown, since one clump drops a great deal of tiny seed.
- 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 sedge weed in the paddy, not only this one. The weed management guide puts them in order for a whole season.
Not Sure It Is Smallflower Umbrella Sedge?
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 Smallflower Umbrella Sedge
What do farmers call smallflower umbrella sedge in Tagalog and other local languages?
How do I control it in my rice field?
Why does it spread so fast in my field?
Get Smallflower Umbrella Sedge out of your field
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