Melochia concatenata: How to Spot and Control It in Rice Fields
Melochia concatenata is a branched, perennial broadleaf weed that farmers call Bankalanan, kaliñgan or marasaluyot. It grows in rainfed lowland rice fields in the Philippines. This page shows you how to spot it by its star shaped hairs and crowded flower heads, and how to control it before it sets seed.
What Is Melochia concatenata?
This weed comes from the family Sterculiaceae, the same plant family as cacao. It has no common English name, so people use its scientific name, Melochia concatenata. In the bukid, farmers call it Bankalanan, kaliñgan or marasaluyot. Since it is a broadleaf weed, it is not a grass or a sedge.
You will see it in rainfed lowland rice fields. As a perennial, the same plant can live past one season if no one removes it. Seed is how it spreads. After flowering, it forms small, flattened round capsules that hold the seeds, and these fall to the ground when ripe. Plants left on bunds and field edges keep feeding seed into the paddy.
| Name | Melochia concatenata |
|---|---|
| Family | Sterculiaceae |
| Weed group | Broadleaves (see the three groups) |
| Local names | Bankalanan, kaliñgan, marasaluyot |
| Life cycle | Perennial |
| Spreads by | Seeds |
| Where it grows | Rainfed lowland rice fields |
How to Identify Melochia concatenata
Look for branched stems that stand upright or spread out. Up close, the stems carry scattered hairs shaped like tiny stars. The leaves are oblong to oval, with a pointed tip and a broad, rounded or heart shaped base. As a broadleaf weed, it has wide leaves with netted veins, unlike grasses and sedges. Its flowers sit crowded in heads at the stem tips or leaf angles. Petals are white, sometimes pink or pale purple.
- Branched stems that stand upright or spread out over the ground.
- Scattered hairs shaped like tiny stars on the stems, best seen up close.
- Oblong to oval leaves with a pointed tip and a rounded or heart shaped base.
- Crowded flower heads at the stem tips or where leaves meet the stem.
- White petals, sometimes pink or pale purple, mixed with thin, narrow bracts.
- Flattened, round seed capsules forming after the flowers fade.
Why It Hurts Your Palay
Melochia concatenata competes with palay for water, fertilizer and light. Its branched stems spread out and shade nearby rice hills, most of all in the first weeks after planting. In rainfed fields, where moisture is often short, this fight for water hurts the rice even more.
Because it is a perennial, a plant that survives one season can come back bigger the next. Each plant also adds seed to the soil. Some seed can get mixed into the harvest and into palay saved for planting. Weeds like this also offer shelter to some insect pests between the rice hills.
How to Control Melochia concatenata
- Pull plants with their whole root, because this perennial can sprout again from a base left in the soil.
- Check bunds and field edges after harvest, since perennial plants there survive the off season and seed into the next crop.
- Weed before the crowded flower heads turn into round capsules, so the plant cannot add seed to the paddy.
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 Melochia concatenata 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 Melochia concatenata 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 Melochia concatenata?
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 Melochia concatenata
What is Melochia concatenata called in local dialects?
How do I control this weed in my rice field?
Why does it come back after I cut it?
Get Melochia concatenata out of your field
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