Horse Purslane in Rice Fields: How to Spot and Control It
Horse purslane is a fleshy, creeping broadleaf weed with green or purplish stems and white to pink flowers. Farmers call it toston, ayam or tabatabukol, and some use alusiman, the same name as purslane. It spreads over rainfed lowland rice fields. This page shows you how to spot it, how to tell it from purslane, and how to control it.
What Is Horse Purslane?
Horse purslane, or Trianthema portulacastrum, belongs to the ice plant family, Aizoaceae. Its local names include alusiman, ayam, kantataba, tabatabukol and toston. Two of these, alusiman and kantataba, also name common purslane, so the two weeds often get mixed up. You will see it in rainfed lowland rice fields, mostly on moist soil that is not flooded.
This weed is an annual. It sprouts, grows, flowers and dies within one season, and it spreads by seed. Its thick, fleshy stems and leaves store water, so it stays green even when the field dries between rains. That is why a few plants left to seed can cover more ground in the next crop, and a careless weeding can leave survivors behind.
| Name | Horse purslane |
|---|---|
| Scientific name | Trianthema portulacastrum |
| Family | Aizoaceae |
| Weed group | Broadleaves (see the three groups) |
| Local names | Alusiman, ayam, kantataba, tabatabukol, toston |
| Life cycle | Annual |
| Spreads by | Seeds |
| Where it grows | Rainfed lowland rice fields |
How to Identify Horse Purslane
Look low, near the soil, for a fleshy plant that creeps flat along the ground. Its stems are flat, juicy and green or purplish. As a broadleaf, its leaves are wide and flat, unlike grasses and sedges. They are oval to almost round, smooth and slightly wavy at the edge. Check how they sit. The leaves come in opposite pairs, and one leaf in each pair is bigger than the other. The small flowers come in white, or in shades from pale pink to purple.
- Low, creeping plants with flat, fleshy stems in green or purplish shades.
- Smooth, oval to almost round leaves with slightly wavy edges.
- Leaves in opposite pairs, with one leaf clearly bigger than its partner.
- Small white, pale pink or purple flowers tucked at the leaf joints.
- Look alike tip: common purslane has yellow flowers and leaves set one by one, not in pairs.
Why It Hurts Your Palay
Horse purslane spreads flat and fast, covering bare soil between the rice rows. It takes water and fertilizer that your palay needs, and young rice feels the loss most. In rainfed fields, where water already runs short, that hurts even more.
Since it stores water in its fleshy stems, it can stay alive after you pull it. Plants left lying on moist soil may hang on and still ripen their seed. Then the next crop starts with even more seedlings. Dense mats also make hand weeding slow and tiring.
How to Control Horse Purslane
- Carry pulled plants out of the field. Their fleshy stems hold water, so they can stay alive on the soil and still ripen seed.
- Weed early, before the small flowers open, so the plants have no chance to drop seed.
- Keep water in the field when rain allows, since standing water keeps this dryland creeper from sprouting and spreading.
- Check the leaves before you plan your control. Unequal opposite pairs mean this weed, while alternate leaves mean common purslane.
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 horse purslane 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 Horse Purslane 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 Horse Purslane?
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 Horse Purslane
What is horse purslane called in the Philippines?
How do I control toston in my rice field?
Why does this weed survive after I pull it?
Get Horse Purslane 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.
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