Recently, a producer called about purslane spreading through her hay and pasture. She wanted practical ways to control it without damaging her forage. She also asked whether her livestock would eat it and whether it could offer nutritional benefits or pose health risks.

Know the plant before you decide what to do

Common purslane (Portulaca oleracea) is a succulent broadleaf plant, not a grass. It grows during the warm season and usually forms a low mat. Look at several features together. The Northern Nevada Extension guide provides photographs of seedlings, leaves, stems and flowers.

Wear gloves when handling an unknown plant and do not taste it. If you are unsure, ask your local Extension office to identify it before you consider feeding or spraying it.

Why it can come back more heavily

A purslane plant can produce as many as 240,000 tiny seeds, which can remain in soil for years. Warm, moist soil favors emergence, especially near the surface after rain or irrigation. Its low mats compete with crops for moisture, nutrients and space. These conditions help explain why irrigated ground can support purslane even in a dry region.

Two findings matter when you weed. In California research, plants pulled one or two weeks after emergence produced no viable seed, but plants pulled at three weeks produced some. In a separate greenhouse study, at least 70% of stem cuttings containing a node, the point where a leaf joins the stem, survived. Remove seedlings promptly and collect larger plants and fragments; uprooting or chopping alone may leave material capable of reproducing.

Killing the visible plants does not remove all the seeds already in the soil. New seedlings can emerge after the treatment, and a thin or bare stand gives them room to grow. A heavier patch the next year does not, by itself, identify what went wrong with the spray. Your control plan needs to prevent new seed production and preserve or restore the forage growing around the weed.

What feeding research can tell you?

Animals’ willingness to eat purslane does not tell you its nitrate or oxalate content. Its use as a human vegetable also does not establish a safe livestock ration. The studies below explain why both the possible benefits and the risks belong in your decision.

Dry matter is the feed remaining after water is removed. The trial percentages cannot be applied directly to pounds of fresh, succulent plants. These studies do not establish a single safe handful, percentage or plant age for wild purslane on your farm. Nor does a lamb trial establish a ration for horses, goats or poultry. Any proposed use needs a confirmed plant identity, analysis of the actual material and a ration suited to the animals that will eat it.

Understand the two main feeding concerns

Nitrate can be converted to nitrite during digestion. Too much nitrite interferes with the blood’s ability to carry oxygen. Cattle, sheep and goats are particularly vulnerable because of this conversion in the rumen. A hungry animal consuming a large amount quickly can be at greater risk.

Purslane also contains soluble oxalates. These can bind calcium and, at sufficiently high exposure, contribute to low blood calcium and kidney injury. A feed’s protein content or green appearance cannot answer either toxicology question.

Take extra care with plants from heavily manured or fertilized ground and after drought followed by rain or irrigation. Purslane poisoning reports included manure-fertilized ground and drought-related conditions. These are reasons to investigate and test, not a way to predict that every plant is toxic or that a plant grown elsewhere is safe.

If animals develop rapid or difficult breathing, weakness, trembling, bloat, staggering, or collapse after eating suspect feed, call your veterinarian immediately. Stop further access, keep animals quiet, and retain plant or feed samples for diagnosis. Do not wait for laboratory results before seeking care.

Start locally and arrange the right forage tests

Until you have a feeding assessment, keep livestock out of dense suspect patches and provide known suitable feed. If the weed is already in hay, keep that hay lot separate while you investigate. Use the following steps to obtain information your veterinarian and livestock nutritionist can use.

Start with help here in Nevada: Contact your county Extension office for help identifying the weed and planning forage sampling. Involve your veterinarian when deciding which tests are needed and what the results mean for your animals. For testing questions, call the Nevada Department of Agriculture Animal Disease Laboratory at 775-353-3709. Explain that you have purslane in hay or pasture and ask whether the laboratory can arrange quantitative nitrate testing and an appropriate oxalate assessment. Its published test schedule includes referral laboratory services but does not list nitrate or oxalate assays. Before collecting or shipping, confirm the receiving laboratory, available tests, sample amount, preservation, cost and turnaround time, and whether your veterinarian should submit the sample.

If an outside laboratory is needed for nitrate analysis, Colorado State University (CSU)’s forage testing service is one option, with a separate F4 nitrate test. Call 970-491-5061 or email soiltestinglab@colostate.edu for its submission instructions. Request nitrate specifically; do not assume a routine nutritional panel includes it.

If feeding remains an option, also request dry matter, crude protein, fiber, and the mineral measurements your nutritionist recommends. University of Nevada, Reno (UNR) Extension’s A Producer’s Guide to Forage Testing explains these measures. They describe feeding value but do not replace nitrate or oxalate assessment.

Collect a sample that represents your pasture or hay lot: For nitrate testing of standing forage, clip at least 20 plants chosen randomly within the area you are assessing, at the height animals would graze. Cut the material into 2- to 3-inch pieces and mix. Keep distinct patches and hay lots separate so clean forage does not dilute a suspect sample. Label the sample and submission form alike. Follow your receiving laboratory’s instructions for sample amount and preservation; if you use CSU, it requests about half a gallon.

For baled hay, use a forage probe and sample each lot separately. UNR Extension’s A Producer’s Guide to Forage Testing provides sampling instructions, probe suppliers, laboratory contacts, and a demonstration video.

Arrange an oxalate assessment through your veterinarian: Ask whether testing for soluble and total oxalates is appropriate and where it can be performed. If specialist advice outside Nevada is needed, the University of California Davis California Animal Health and Food Safety Toxicology service provides feed testing and veterinary toxicology consultation. The Davis laboratory can be reached at 530-752-8700. Confirm whether the specific oxalate analysis can be arranged, who should submit the sample, and how to preserve it before shipping.

Read the report with the units attached: Check whether the result is nitrate (NO3) or nitrate nitrogen (NO3-N), whether it is in parts per million (ppm), milligrams per kilogram, or percent, and whether it is expressed on a dry-matter basis. NO3-N × 4.4 is approximately NO3 when the other units and moisture basis match; 1% equals 10,000 ppm. These conversions do not establish a safe feeding level.

Make the feeding decision from the whole ration: Give your veterinarian or nutritionist the reports, animal species and production stage, expected intake, other feeds, water source, and any herbicide history. Ask whether the material should be excluded or whether a tested amount can fit a balanced ration. A low nitrate result alone does not resolve an oxalate concern.

Drying or cooking does not settle the safety question

If you choose to test it as a feed, do not assume that making hay removes nitrate. Nitrate usually persists in stored hay. Fermentation can lower nitrate in silage, but the reduction varies, so test the finished material before feeding it.

A purslane food-processing study found that boiling reduced total oxalate by 27%, leaving much of it behind. That study did not test livestock safety. It does not provide a recipe for turning an untested weed patch into safe animal feed.

There is also a haymaking problem. Succulent purslane can remain wet after surrounding alfalfa dries, contributing to mold and heating in bales. Check the moist material in the windrow before baling; dry leaves elsewhere in the windrow can be misleading.

Control purslane while protecting the rest of the pasture

If earlier spraying damaged forage or failed to control the weed, review that application before treating another pasture. Keep the label or invoice, product and EPA registration number, amount used, treated acreage, tank additives, date and weather. If a contractor sprayed, request the record. Ask Extension to compare those details with the forage species and symptoms. Product choice, spray overlap, drift and other plant stresses need investigation before the treatment is repeated.

Use this sequence in your other pastures. It combines early removal, a crop-compatible treatment where needed, and repeated checks for seedlings. The California timing study supports removing plants within the first two weeks after emergence, so a weekly walk during active emergence is a practical way to find them in time.

Do not use grazing as a purslane clean-up treatment while feed safety is unresolved. Likewise, mowing a pasture at a height suitable for the forage may pass above purslane’s low mat. Check the actual weeds afterward and remove survivors; a freshly cut field can still contain plants capable of setting seed.

Help desirable forage cover bare ground again

Have the surviving forage assessed before deciding to replace the whole stand. Where recovery is possible, improve grazing rest, irrigation and fertility. If reseeding is needed, first check the previous herbicide’s planting restrictions. Choose forage suited to your water supply and soil, use a recent soil test to guide fertilizer, and arrange suitable seed placement and seed-to-soil contact. Your county Extension office or local NRCS office can help select the mixture and planting method.

If herbicide residues are suspected, the NC State bioassay guide explains how to compare plant growth in representative suspect soil and untreated soil. Keep different soil areas and spray overlaps separate, grow the intended forage or an appropriate sensitive test plant, and compare shoots and roots about three weeks after germination. Work with Extension to select the test. A favorable pot result does not cancel a label’s planting interval or required field test.

Choose herbicides for the crop you are protecting

A product suitable for grass pasture can injure alfalfa. The three examples below are for different sites and exact formulations. All considered as active products in Nevada’s pesticide database as of September 24, 2026. They are examples, not endorsements or a complete list of options.

Before buying, open the Nevada pesticide product database, enter the product name or EPA registration number, select Active, and search. Match the result to the container. Then read that container’s label for your crop, weed size, application method, and restrictions. A brand name or an active ingredient alone is insufficient.

Prevent new seedlings in established grass

 Alabama Extension’s forage guidance prefers at least 0.25 inch of rainfall within seven days for Prowl H2O activity. Plan for activation before you spray, and check that your irrigation method is allowed by the label.

A label’s grazing or harvest interval addresses pesticide use. It does not certify that purslane is safe feed. Keep the livestock feeding assessment separate from permission to return to a treated field. Measure the area, calibrate the sprayer, and follow the label’s protective-equipment, drift, water-protection, and worker-entry instructions.

Before mixing pesticide, please be guided by the Extension’s boom-sprayer calibration guide published by Colorado State University. It explains how to check the equipment, measure travel speed and nozzle output using water, and calculate the application volume.

If you hire an applicator, use a Nevada-licensed pest-control business. Restricted-use pesticides require the appropriate certified applicator or supervision in Nevada; that is different from a commercial pest-control license. The NDA certification page provides training and examination information, and its licensing guidance explains who needs a business license.

For a vegetable crop, mixed forage stand, or site outside these examples, contact your county Extension office with the crop, growth stage, purslane size, recent herbicides, irrigation method, and planned harvest or reseeding date. Those details determine which label fits. Keep checking the field after treatment and remove escapes before they replenish the seed supply.

References and additional resources

1. Ayers, P. D., & Bosley, B. (2005, January). Pesticide sprayer calibration fundamentals. Colorado State University Extension. https://extension.colostate.edu/resource/sprayer-calibration-fundamentals/ 
2. BASF Corporation. (2023). Beyond Xtra herbicide (EPA Reg. No. 241-441) [Pesticide label]. https://assets.greenbook.net/23-31-31-30-05-2024-Beyond_Xtra_Herbicide_-_label.pdf 
3. BASF Corporation. (2024, September 25). Prowl H2O herbicide (EPA Reg. No. 241-418) [Pesticide label]. https://www3.epa.gov/pesticides/chem_search/ppls/000241-00418-20240925.pdf 
4. California Animal Health and Food Safety Laboratory System. (n.d.). Toxicology. University of California, Davis. https://cahfs.vetmed.ucdavis.edu/tests-and-fees/diagnostic-services/toxicology 
5. Chauhan, B. S., & Johnson, D. E. (2009). Seed germination ecology of Portulaca oleracea L.: An important weed of rice and upland crops. Annals of Applied Biology, 155(1), 61–69. https://doi.org/10.1111/j.1744-7348.2009.00320.x 
6. Colorado State University Extension. (n.d.). Reseeding small acreage pastures. https://extension.colostate.edu/resource/reseeding/ 
7. Colorado State University Soil, Water and Plant Testing Laboratory. (n.d.). Forage sampling, submissions, pricing. https://agsci.colostate.edu/soiltestinglab/soil-water-plant-testing-laboratory/forage-samples/ 
8. Cudney, D. W., Elmore, C. L., & Molinar, R. H. (2007). Common purslane (Pest Notes Publication 7461). University of California Agriculture and Natural Resources. https://ipm.ucanr.edu/home-and-landscape/common-purslane/ 
9. Donaldson, S., & Hanson Mazet, W. (2010). A Northern Nevada homeowner’s guide to identifying and managing common purslane (FS-10-26). University of Nevada, Reno Extension. https://extension.unr.edu/publication.aspx?PubID=3399 
10. Goosey, H., Carr, W., King, M., Jones, C., & Severson, D. (2024, March). Nitrate toxicity of Montana forages (MT200205AG). Montana State University Extension. https://animalrangeextension.montana.edu/forage/nitratetoxicity.html 
11. Haar, M. J., & Fennimore, S. A. (2003). Evaluation of integrated practices for common purslane (Portulaca oleracea) management in lettuce (Lactuca sativa). Weed Technology, 17(2), 229–233. https://doi.org/10.1614/0890-037X(2003)017[0229:EOIPFC]2.0.CO;2   
12. Leinfelder-Miles, M. M., & Canevari, M. M. (2017, August 16). Common purslane—Problems and management in alfalfa fields. University of California Agriculture and Natural Resources. https://ucanr.edu/blog/sjc-and-delta-field-crops/article/common-purslane-problems-and-management-alfalfa-fields 
13. Mayahi, S., Chaji, M., Shojaeian, K., & Jalilvand, G. (2025). Effect of Portulaca oleracea on carcass traits, fatty acid composition, meat quality and oxidative stability of Arabi lambs. Veterinary Medicine and Science, 11(2), Article e70224. https://doi.org/10.1002/vms3.70224 
14. Molinar, R. H., Cudney, D. W., Elmore, C. L., & Sanders, A. (2009). Spotted spurge and other spurges (Pest Notes Publication 7445). University of California Agriculture and Natural Resources. https://ipm.ucanr.edu/home-and-landscape/spotted-spurge-and-other-spurges/ 
15. Neal, J. (2021, August 4). Conducting a bioassay for herbicide residues. NC State Extension. https://content.ces.ncsu.edu/conducting-a-bioassay-for-herbicide-residues 
16. Nevada Department of Agriculture. (n.d.-a). Official pesticide product database. Retrieved September 24, 2026, from https://nv.certifyag.com/PestPublic/Products.aspx 
17. Nevada Department of Agriculture. (n.d.-b). Pesticide applicator certification and training. https://agri.nv.gov/Plant/Environmental_Services/Pesticide_Applicator_Cert/ 
18. Nevada Department of Agriculture. (n.d.-c). Who must have a pest control license. https://agri.nv.gov/Plant/PEST/Who_must_have_a_pest_control_license/ 
19. Nevada Department of Agriculture. (2026, August 1). ADL fee schedule and laboratory policy. https://agri.nv.gov/Animals/Animal_Disease/ADL_Fee_Schedule/ 
20. Nufarm, Inc. (2025, January 29). WeedMaster XHL (EPA Reg. No. 71368-139) [Pesticide label]. https://www3.epa.gov/pesticides/chem_search/ppls/071368-00139-20250129.pdf 
21. Orloff, N., Mangold, J., & Seipel, T. (2020). A guide to diagnosing non-target herbicide injury on plants (EB0232). Montana State University Extension. https://www.montana.edu/extension/Full_HTML_Pubs/herbicideinjuryguide/diagnose.html 
22. Poeydomenge, G. Y., & Savage, G. P. (2007). Oxalate content of raw and cooked purslane. Journal of Food, Agriculture and Environment, 5(1), 124–128. https://www.wflpublisher.com/Abstract/745 
23. Proctor, C. A., Gaussoin, R. E., & Reicher, Z. J. (2011). Vegetative reproduction potential of common purslane (Portulaca oleracea). Weed Technology, 25(4), 694–697. https://doi.org/10.1614/WT-D-11-00045.1 
24. Russell, D., & Tredaway, J. A. (2024, January 18). Prowl H2O on forages. Alabama Cooperative Extension System. https://www.aces.edu/blog/topics/farming/prowl-h2o-on-forages/ 
25. Schmid, R. D. (2024, September). Houseplants and ornamentals toxic to animals. Merck Veterinary Manual. https://www.merckvetmanual.com/toxicology/poisonous-plants/houseplants-and-ornamentals-toxic-to-animals 
26. Simões, J. G., Medeiros, R. M. T., Medeiros, M. A., Olinda, R. G., Dantas, A. F. M., & Riet-Correa, F. (2018). Nitrate and nitrite poisoning in sheep and goats caused by ingestion of Portulaca oleracea. Pesquisa Veterinária Brasileira, 38(8), 1549–1553. https://doi.org/10.1590/1678-5150-PVB-5550 
27. Sosa, E., Azaldegui, I., Barale, J., Sainz Rozas, H., Scioli, V., Poo, J., Lauro, A., Ovelar, F., Pachiani, M., García, J. A., & Cantón, G. (2025). Nitrate and nitrite acute poisoning in feedlot cattle caused by ingestion of Portulaca oleracea. Tropical Animal Health and Production, 57, Article 299. https://doi.org/10.1007/s11250-025-04555-9 
28. Thompson, L. J. (2026, August). Nitrate and nitrite poisoning in animals. Merck Veterinary Manual. https://www.merckvetmanual.com/toxicology/nitrate-and-nitrite-poisoning/nitrate-and-nitrite-poisoning-in-animals 
29. University of Nevada, Reno Extension. (n.d.). County offices. https://extension.unr.edu/county-offices.aspx 
30. Utah State University Extension. (n.d.). Pastures. https://extension.usu.edu/smallfarms/plants/pastures 
31. Waaswa, A., & Shane, T. (2025). A producer’s guide to forage testing. University of Nevada, Reno Extension. https://extension.unr.edu/publication.aspx?PubID=6985 

Recently, a producer called about purslane spreading through her hay and pasture. She wanted practical ways to control it without damaging her forage. She also asked whether her livestock would eat it and whether it could offer nutritional benefits or pose health risks.

Know the plant before you decide what to do

Common purslane (Portulaca oleracea) is a succulent broadleaf plant, not a grass. It grows during the warm season and usually forms a low mat. Look at several features together. The Northern Nevada Extension guide provides photographs of seedlings, leaves, stems and flowers.

Wear gloves when handling an unknown plant and do not taste it. If you are unsure, ask your local Extension office to identify it before you consider feeding or spraying it.

Why it can come back more heavily

A purslane plant can produce as many as 240,000 tiny seeds, which can remain in soil for years. Warm, moist soil favors emergence, especially near the surface after rain or irrigation. Its low mats compete with crops for moisture, nutrients and space. These conditions help explain why irrigated ground can support purslane even in a dry region.

Two findings matter when you weed. In California research, plants pulled one or two weeks after emergence produced no viable seed, but plants pulled at three weeks produced some. In a separate greenhouse study, at least 70% of stem cuttings containing a node, the point where a leaf joins the stem, survived. Remove seedlings promptly and collect larger plants and fragments; uprooting or chopping alone may leave material capable of reproducing.

Killing the visible plants does not remove all the seeds already in the soil. New seedlings can emerge after the treatment, and a thin or bare stand gives them room to grow. A heavier patch the next year does not, by itself, identify what went wrong with the spray. Your control plan needs to prevent new seed production and preserve or restore the forage growing around the weed.

What feeding research can tell you?

Animals’ willingness to eat purslane does not tell you its nitrate or oxalate content. Its use as a human vegetable also does not establish a safe livestock ration. The studies below explain why both the possible benefits and the risks belong in your decision.

Dry matter is the feed remaining after water is removed. The trial percentages cannot be applied directly to pounds of fresh, succulent plants. These studies do not establish a single safe handful, percentage or plant age for wild purslane on your farm. Nor does a lamb trial establish a ration for horses, goats or poultry. Any proposed use needs a confirmed plant identity, analysis of the actual material and a ration suited to the animals that will eat it.

Understand the two main feeding concerns

Nitrate can be converted to nitrite during digestion. Too much nitrite interferes with the blood’s ability to carry oxygen. Cattle, sheep and goats are particularly vulnerable because of this conversion in the rumen. A hungry animal consuming a large amount quickly can be at greater risk.

Purslane also contains soluble oxalates. These can bind calcium and, at sufficiently high exposure, contribute to low blood calcium and kidney injury. A feed’s protein content or green appearance cannot answer either toxicology question.

Take extra care with plants from heavily manured or fertilized ground and after drought followed by rain or irrigation. Purslane poisoning reports included manure-fertilized ground and drought-related conditions. These are reasons to investigate and test, not a way to predict that every plant is toxic or that a plant grown elsewhere is safe.

If animals develop rapid or difficult breathing, weakness, trembling, bloat, staggering, or collapse after eating suspect feed, call your veterinarian immediately. Stop further access, keep animals quiet, and retain plant or feed samples for diagnosis. Do not wait for laboratory results before seeking care.

Start locally and arrange the right forage tests

Until you have a feeding assessment, keep livestock out of dense suspect patches and provide known suitable feed. If the weed is already in hay, keep that hay lot separate while you investigate. Use the following steps to obtain information your veterinarian and livestock nutritionist can use.

Start with help here in Nevada: Contact your county Extension office for help identifying the weed and planning forage sampling. Involve your veterinarian when deciding which tests are needed and what the results mean for your animals. For testing questions, call the Nevada Department of Agriculture Animal Disease Laboratory at 775-353-3709. Explain that you have purslane in hay or pasture and ask whether the laboratory can arrange quantitative nitrate testing and an appropriate oxalate assessment. Its published test schedule includes referral laboratory services but does not list nitrate or oxalate assays. Before collecting or shipping, confirm the receiving laboratory, available tests, sample amount, preservation, cost and turnaround time, and whether your veterinarian should submit the sample.

If an outside laboratory is needed for nitrate analysis, Colorado State University (CSU)’s forage testing service is one option, with a separate F4 nitrate test. Call 970-491-5061 or email soiltestinglab@colostate.edu for its submission instructions. Request nitrate specifically; do not assume a routine nutritional panel includes it.

If feeding remains an option, also request dry matter, crude protein, fiber, and the mineral measurements your nutritionist recommends. University of Nevada, Reno (UNR) Extension’s A Producer’s Guide to Forage Testing explains these measures. They describe feeding value but do not replace nitrate or oxalate assessment.

Collect a sample that represents your pasture or hay lot: For nitrate testing of standing forage, clip at least 20 plants chosen randomly within the area you are assessing, at the height animals would graze. Cut the material into 2- to 3-inch pieces and mix. Keep distinct patches and hay lots separate so clean forage does not dilute a suspect sample. Label the sample and submission form alike. Follow your receiving laboratory’s instructions for sample amount and preservation; if you use CSU, it requests about half a gallon.

For baled hay, use a forage probe and sample each lot separately. UNR Extension’s A Producer’s Guide to Forage Testing provides sampling instructions, probe suppliers, laboratory contacts, and a demonstration video.

Arrange an oxalate assessment through your veterinarian: Ask whether testing for soluble and total oxalates is appropriate and where it can be performed. If specialist advice outside Nevada is needed, the University of California Davis California Animal Health and Food Safety Toxicology service provides feed testing and veterinary toxicology consultation. The Davis laboratory can be reached at 530-752-8700. Confirm whether the specific oxalate analysis can be arranged, who should submit the sample, and how to preserve it before shipping.

Read the report with the units attached: Check whether the result is nitrate (NO3) or nitrate nitrogen (NO3-N), whether it is in parts per million (ppm), milligrams per kilogram, or percent, and whether it is expressed on a dry-matter basis. NO3-N × 4.4 is approximately NO3 when the other units and moisture basis match; 1% equals 10,000 ppm. These conversions do not establish a safe feeding level.

Make the feeding decision from the whole ration: Give your veterinarian or nutritionist the reports, animal species and production stage, expected intake, other feeds, water source, and any herbicide history. Ask whether the material should be excluded or whether a tested amount can fit a balanced ration. A low nitrate result alone does not resolve an oxalate concern.

Drying or cooking does not settle the safety question

If you choose to test it as a feed, do not assume that making hay removes nitrate. Nitrate usually persists in stored hay. Fermentation can lower nitrate in silage, but the reduction varies, so test the finished material before feeding it.

A purslane food-processing study found that boiling reduced total oxalate by 27%, leaving much of it behind. That study did not test livestock safety. It does not provide a recipe for turning an untested weed patch into safe animal feed.

There is also a haymaking problem. Succulent purslane can remain wet after surrounding alfalfa dries, contributing to mold and heating in bales. Check the moist material in the windrow before baling; dry leaves elsewhere in the windrow can be misleading.

Control purslane while protecting the rest of the pasture

If earlier spraying damaged forage or failed to control the weed, review that application before treating another pasture. Keep the label or invoice, product and EPA registration number, amount used, treated acreage, tank additives, date and weather. If a contractor sprayed, request the record. Ask Extension to compare those details with the forage species and symptoms. Product choice, spray overlap, drift and other plant stresses need investigation before the treatment is repeated.

Use this sequence in your other pastures. It combines early removal, a crop-compatible treatment where needed, and repeated checks for seedlings. The California timing study supports removing plants within the first two weeks after emergence, so a weekly walk during active emergence is a practical way to find them in time.

Do not use grazing as a purslane clean-up treatment while feed safety is unresolved. Likewise, mowing a pasture at a height suitable for the forage may pass above purslane’s low mat. Check the actual weeds afterward and remove survivors; a freshly cut field can still contain plants capable of setting seed.

Help desirable forage cover bare ground again

Have the surviving forage assessed before deciding to replace the whole stand. Where recovery is possible, improve grazing rest, irrigation and fertility. If reseeding is needed, first check the previous herbicide’s planting restrictions. Choose forage suited to your water supply and soil, use a recent soil test to guide fertilizer, and arrange suitable seed placement and seed-to-soil contact. Your county Extension office or local NRCS office can help select the mixture and planting method.

If herbicide residues are suspected, the NC State bioassay guide explains how to compare plant growth in representative suspect soil and untreated soil. Keep different soil areas and spray overlaps separate, grow the intended forage or an appropriate sensitive test plant, and compare shoots and roots about three weeks after germination. Work with Extension to select the test. A favorable pot result does not cancel a label’s planting interval or required field test.

Choose herbicides for the crop you are protecting

A product suitable for grass pasture can injure alfalfa. The three examples below are for different sites and exact formulations. All considered as active products in Nevada’s pesticide database as of September 24, 2026. They are examples, not endorsements or a complete list of options.

Before buying, open the Nevada pesticide product database, enter the product name or EPA registration number, select Active, and search. Match the result to the container. Then read that container’s label for your crop, weed size, application method, and restrictions. A brand name or an active ingredient alone is insufficient.

Prevent new seedlings in established grass

 Alabama Extension’s forage guidance prefers at least 0.25 inch of rainfall within seven days for Prowl H2O activity. Plan for activation before you spray, and check that your irrigation method is allowed by the label.

A label’s grazing or harvest interval addresses pesticide use. It does not certify that purslane is safe feed. Keep the livestock feeding assessment separate from permission to return to a treated field. Measure the area, calibrate the sprayer, and follow the label’s protective-equipment, drift, water-protection, and worker-entry instructions.

Before mixing pesticide, please be guided by the Extension’s boom-sprayer calibration guide published by Colorado State University. It explains how to check the equipment, measure travel speed and nozzle output using water, and calculate the application volume.

If you hire an applicator, use a Nevada-licensed pest-control business. Restricted-use pesticides require the appropriate certified applicator or supervision in Nevada; that is different from a commercial pest-control license. The NDA certification page provides training and examination information, and its licensing guidance explains who needs a business license.

For a vegetable crop, mixed forage stand, or site outside these examples, contact your county Extension office with the crop, growth stage, purslane size, recent herbicides, irrigation method, and planned harvest or reseeding date. Those details determine which label fits. Keep checking the field after treatment and remove escapes before they replenish the seed supply.

References and additional resources

1. Ayers, P. D., & Bosley, B. (2005, January). Pesticide sprayer calibration fundamentals. Colorado State University Extension. https://extension.colostate.edu/resource/sprayer-calibration-fundamentals/ 
2. BASF Corporation. (2023). Beyond Xtra herbicide (EPA Reg. No. 241-441) [Pesticide label]. https://assets.greenbook.net/23-31-31-30-05-2024-Beyond_Xtra_Herbicide_-_label.pdf 
3. BASF Corporation. (2024, September 25). Prowl H2O herbicide (EPA Reg. No. 241-418) [Pesticide label]. https://www3.epa.gov/pesticides/chem_search/ppls/000241-00418-20240925.pdf 
4. California Animal Health and Food Safety Laboratory System. (n.d.). Toxicology. University of California, Davis. https://cahfs.vetmed.ucdavis.edu/tests-and-fees/diagnostic-services/toxicology 
5. Chauhan, B. S., & Johnson, D. E. (2009). Seed germination ecology of Portulaca oleracea L.: An important weed of rice and upland crops. Annals of Applied Biology, 155(1), 61–69. https://doi.org/10.1111/j.1744-7348.2009.00320.x 
6. Colorado State University Extension. (n.d.). Reseeding small acreage pastures. https://extension.colostate.edu/resource/reseeding/ 
7. Colorado State University Soil, Water and Plant Testing Laboratory. (n.d.). Forage sampling, submissions, pricing. https://agsci.colostate.edu/soiltestinglab/soil-water-plant-testing-laboratory/forage-samples/ 
8. Cudney, D. W., Elmore, C. L., & Molinar, R. H. (2007). Common purslane (Pest Notes Publication 7461). University of California Agriculture and Natural Resources. https://ipm.ucanr.edu/home-and-landscape/common-purslane/ 
9. Donaldson, S., & Hanson Mazet, W. (2010). A Northern Nevada homeowner’s guide to identifying and managing common purslane (FS-10-26). University of Nevada, Reno Extension. https://extension.unr.edu/publication.aspx?Pubtitle=3399 
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12. Leinfelder-Miles, M. M., & Canevari, M. M. (2017, August 16). Common purslane—Problems and management in alfalfa fields. University of California Agriculture and Natural Resources. https://ucanr.edu/blog/sjc-and-delta-field-crops/article/common-purslane-problems-and-management-alfalfa-fields 
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