Cyperus imbricatus: How to Spot and Control Shingle Flatsedge
Cyperus imbricatus, or shingle flatsedge, is a coarse, tufted sedge weed of irrigated and rainfed lowland rice fields in the Philippines. Farmers know it as ballayang, balabalongutan or obod obod. This page shows how to spot it by its stems and flower heads, and how to control it before it spreads.
What Is Cyperus imbricatus?
This damo is a sedge from the Cyperaceae family. Its English name is shingle flatsedge, and farmers know it as ballayang, balabalongutan or obod obod. Cyperus imbricatus grows in both irrigated and rainfed lowland rice fields.
It is usually a perennial, though some plants live for one season only. It spreads mainly by seed, and sometimes by rhizomes, which are stems that creep under the soil. Its flower heads hold many long spikelets, so one plant can leave plenty of seed behind. A clump that survives the season can also sprout again with the next crop. That is why removing whole clumps, roots and all, works better than cutting. Start early, while the tufts are still small and easy to lift.
| Name | Cyperus imbricatus |
|---|---|
| English name | Shingle flatsedge |
| Family | Cyperaceae |
| Weed group | Sedges (see the three groups) |
| Local names | Ballayang, balabalongutan, obod obod |
| Life cycle | Perennial, sometimes annual |
| Spreads by | Seeds, sometimes rhizomes |
| Where it grows | Irrigated and rainfed lowland rice fields |
How to Identify Cyperus imbricatus
Like other sedges, it has a solid, triangular stem with no nodes. The plant looks coarse and tufted, and it grows upright. Its leaves stay shorter than the stem. At the top, it carries a compound, umbrella shaped flower head. This head starts out green when young and turns brown as it matures. Look closely and you will see many long spikelets packed in each head.
- Coarse, upright tufts with many stems growing from one base.
- Three sided stems that feel solid, with no joints along the length.
- Leaves shorter than the stems, so the flower heads stand above the leaves.
- A branched, umbrella shaped flower head, green when young and brown when mature.
- Many long spikelets crowded in each flower cluster.
Why It Hurts Your Palay
Like most sedges, Cyperus imbricatus competes with palay for light, water and fertilizer. Its coarse tufts take up space between the rice hills, and its roots draw on the same nutrients your crop needs. Because it is usually a perennial, an old tuft can keep taking those resources crop after crop.
Its flower heads hold many long spikelets, so missed plants leave a lot of seed in your soil. That seed can also end up in harvested palay and lower the quality of seed you keep. Thick tufts give rats and insect pests a place to hide near the rice hills.
How to Control Cyperus imbricatus
- Dig out the whole tuft with its roots and any rhizomes, because a clump cut at the surface can regrow.
- Remove plants while the flower heads are still green, before they turn brown and shed seed.
- Clear tufts from bunds and canal edges, where perennial clumps can wait out the dry season.
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 Cyperus imbricatus 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 Cyperus imbricatus 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.
- Plow and harrow well, and rake out the runners, roots or pieces you turn up. A small piece left in wet soil can grow a new plant.
- 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 Cyperus imbricatus?
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 Cyperus imbricatus
What do farmers call Cyperus imbricatus in the local language?
How do I control it in my rice field?
Why is it hard to get rid of?
Get Cyperus imbricatus out of your field
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