Chapter Meetings & Events

Through at least Summer 2021, all Chapter activities will continue to take place virtually via Zoom. Our virtual events will be announced at least two weeks in advance to our email list subscribers. To join our email list, please contact

City Nature Challenge – April & May 2021

Join us in participating in the City Nature Challenge 2021!

At April’s Chapter meeting, our guest speaker was Jeny Davis, coordinator of the Desert Botanical Garden’s Metro Phoenix EcoFlora. We invite you to watch the recording of her presentation to learn about the City Nature Challenge and how you can participate.

Then, from April 30th to May 3rd, use iNaturalist to document as many plants, animals, and other living things that you can find. Be sure to join the City Nature Challenge 2021: Great Phoenix Area project to see all of the observations made by you and others.

From May 4th-9th, browse the project on iNaturalist to help to identify what others observed.

On May 10th, results will be announced. Prizes will be awarded for the most observations made, most species observed, and most identifications made!


Our events are open to Chapter members as well as the general public, unless stated otherwise. If you’re interested in becoming a Chapter member, please view the Membership page. Yearly membership is just $30 for individuals, $15 for students, and $35 for families.


Additional Chapter Announcements

Invasive Species Alert: Stinknet

Help control the spread of Stinknet to protect native habitats and prevent wildfires!

Also known as Globe chamomile (Oncosiphon pilluliferum), Stinknet is a noxious weed that is spreading quickly throughout central Arizona. In Spring, flowering Stinknet plants can easily be spotted. If you have it on your property, take action to remove and dispose of the plants before the seeds ripen and have a chance to spread!

Learn more by downloading our informative Stinknet pamphlet, which is available in English and Spanish.

Stinknet plant flowering.

Stinknet plant flowering. Photo credit: Lisa Rivera


Wildfire Precautions

To help prevent wildfires in our public lands, do not drive over dry grass, do not smoke in vegetated areas, and do not use fireworks. Also, take extra care to obey additional fire restrictions that may be in place.

For the latest information about wildfires in Arizona or anywhere in the US, visit the national Incident Information System (InciWeb).

Image credit: Bureau of Land Management – Arizona.


Recreate Responsibly

The Arizona Office of Tourism’s website provides information about responsible recreation, including leave no trace principles, safety precautions, and the current status of public lands in Arizona.

If you opt to explore our beautiful desert parks and public lands that are open, please do so safely, plan ahead, and have a back-up plan in case your chosen location is crowded or closed.


Join our virtual community!

To stay up to date on our meetings and other activities, please join our email list.

Follow the AZNPS Phoenix Chapter’s Facebook page for more information about local native plants news and events!

We also invite you to follow our Chapter on Instagram and use the hashtag #aznativeplants to help us raise awareness of Arizona’s amazing native plants!



Seeking native plants to use in landscaping?

Native Landscaping Plants

If you would like to learn which plants are native to our area, we invite you to view our Chapter’s List of Recommended Native Landscaping Plants (draft version). It highlights plants that are: 1) native to the Phoenix metro area, 2) beneficial to wildlife, 3) low-water-use, 4) relatively easy to care for, and 5) generally available at local nurseries or seed suppliers.

Our Chapter President’s Top 20 Native Landscaping Plants for Metro Phoenix are presented in a webinar recording.

The AZNPS Grow Native resource pages also have additional information about landscaping with native plants, including planning your garden and pamphlets available to download.

Local Nurseries & Plant Sales

We’ve compiled a list of metro Phoenix nurseries that generally offer a selection of native plants. Some have more variety than others, and inventory changes frequently or may be seasonal. So, it is best to inquire with a few nurseries by phone or email to determine which one suits your needs. Due to precautionary measures currently in place, please contact a nursery directly to determine if they have special operating hours or procedures.

In addition, many local organizations hold plant sale fundraisers in the Spring and Fall. We’ll update this announcement when any local plant sales take place.

Wildflower Seeds

Monsoon season and fall are terrific times to add wildflower seeds to your landscape, assuming it rains! For a wide variety of Arizona native plant seeds, we recommend the following sources:

Maricopa Native Seed Library – This new local project offers native seeds for free! Similar in format to other seed libraries, the public may obtain up to 3 seed packets per month. Available at several Maricopa Community Colleges libraries.

Native Seeds/SEARCH – Purchase seeds online or visit their store in Tucson.

Borderlands Restoration Network – Purchase seeds online or visit their nursery in Patagonia.

If you feel there’s a local nursery, native plant fundraiser, or seed supplier we should add to our list, please let us know!

Chapter Leadership

Name Role Contact
Lisa Rivera President
Pam McMillie Vice President
Danielle Carlock Treasurer
Kathy Balman Secretary

Volunteering Opportunities

Want to get involved? We've got just the thing!

Volunteer activities are currently limited due to COVID-19 precautions. We recommend the following citizen science projects that you can safely participate in on your own while social distancing at home or taking a walk in your neighborhood.

Citizen Science Opportunities

Metro Phoenix EcoFlora

An iNaturalist project focused on plants found in urban environments. There are also monthly EcoQuest challenges that focus on certain species. Add your photo observations to the project. Or, if plant identification is your superpower, help to ID what others saw!

Nature’s Notebook

Document the seasonal changes in plants or animals near your home by becoming a USA – National Phenology Network observer.

Desert Defenders

A special initiative in metro Phoenix to identify and map invasive plants. There is also a special project dedicated to locating stinknet (Oncosiphon piluliferum/pilulifer).

Buffelgrass Green-up

Contribute invasive buffelgrass observations to the USA – National Phenology Network’s Buffelgrass Green-Up phenophase map.

Western Monarch Milkweed Mapper

If you see milkweed plants or monarch butterflies, eggs, or caterpillars while outdoors, take a photo and submit your sighting to this regional project.

Southwest Monarch Study

Monarchs need milkweed and nectar plants, so hopefully you have these growing in your yard or neighborhood! Join this monarch “tagging” project to help document Western monarch migration.


Native plants attract a variety of birds. Report the type of birds you see in your yard, neighborhood, or local park.

Bumble Bee Watch

Native flowering plants are essential for bumble bees. Help scientists track their populations by submitting photos of the ones you see.

If you have a rain gauge at home (or decide to purchase one), join this Arizona rainfall monitoring network to submit your daily rainfall totals.


Access digitized natural history data online to help transcribe and decipher field notebooks, photographs, museum labels, and data sheets from around the world.


Select from a variety of online projects to contribute to real academic research from your own computer.

Libraries as Hubs for Citizen Science

Visit one of six local libraries loaning out citizen science tools and supplies.

Chapter News

Plant Profile: Engelmann’s Hedgehog Cactus

Posted on Mar 30, 2021

Strawberries of the Desert

By Kathleen M. McCoy, Master Naturalist, AZNPS Phoenix Chapter Member

Leer en español

Many Echinocereus, including Engelmann’s hedgehog or Strawberry cactus (E. engelmannii), produce a very delicious fruit reported to taste a lot like strawberries (Eppel, 2012). The tiny red fruit, in keeping with the stature of the diminutive Engelmann’s hedgehog, comes from a 4 to 12 inch tall cylindrical cactus with 8 to 14 ribs. The inch-long fruit can be circular to egg-shaped with a fleshy white pulp. As the fruit reaches maturity, the deciduous spines fall off (Tibbits, 2020).

In contrast, its large 2 to 3 inch wide tubular flowers seem oversized. The brilliant flowers blossom from April to May ranging in color from bright magenta to pale pink, but only last for 5 days opening in the morning and closing at night.

Photo credit: Lisa Rivera

Native to the southwestern US and northern Mexico, this slow-growing succulent’s name is due to short, spiny stems which resemble hedgehogs. Their 2 inch curved radial spines may be red, yellow, white, or gray. Protection from rodents and other herbivores is provided by the sharp spines, sometimes covering the whole plant. The spines also give shade which keeps the stem at an optimal temperature. To reduce water loss, the cactus produces a waxy coat which is heaviest on the plant section receiving the most sun. In the evenings, Hedgehog cacti open their stomata (pores) to perform an oxygen and carbon dioxide exchange (Lady Bird Johnson Wildflower Center, 2010).

Photo credit: Lisa Rivera

Found on hillsides, desert plains, and scrubland in generally dry, sunny locations, this perennial appears from sea level to 5,000 feet. They form medium-sized clusters or colonies with as many as 50 to 60 stems and spread 3 feet wide. The stems of these very common cacti are initially upright but with old age may fall to the ground and grow laterally.

Photo credit: Lisa Rivera

At least 8 varieties of E. engelmannii are found in the Sonoran Desert and in garden nurseries as well. These pretty little succulents can be propagated from seeds sown in the spring or offsets grown from a base plant. To thrive, potted or wild, a Hedgehog cactus needs nearly full sun for 6 or more hours daily and good drainage (VanZile, 2021). Overwatering is likely to produce root rot. If potted, a small dose of diluted fertilizer once or twice a month will maintain a healthy plant.

As a food plant, hedgehog cacti have been used by indigenous peoples of the Southwest. Ripe fruit has been eaten raw and dried for future use, prepared as a sweet snack for children, and converted to a jam or jelly. The inner stem, described as a survival food, is best eaten boiled or roasted.

The Hedgehog cactus has additional properties valuable to desert dwellers and others. The soothing topical qualities of the inner stem can be applied to burns including sunburn. Taken internally, reports suggest that the inner stem also has potential to lower blood sugar and cholesterol levels (Kane, 2020). Other than the prickly thorns, no cautions exist for the fruit or stems. The biggest challenge presented by the Hedgehog cactus is to find the ripe fruit before the birds and rodents have a special strawberry-flavored treat!

Photo credit: Lisa Rivera


Eppel, A. (2012). Plants of Arizona: A Field Guide. Rowan and Littlefield: Helena, Montana.

Kane, C.W. (2020). Sonoran Desert Food Plants. Lincoln Town Press: USA.

Lady Bird Johnson Wildflower Center. (2010). Echinocereus engelmannii.

Tibbits, D. (2020). Hedgehog cactus information. SFGATE.

VanZile, J. (2021). How to grow Echinocereus cacti. The Spruce.

Plant Profile: New Mexico Thistle

Posted on Feb 28, 2021

Stop Before you Chop

By Kathleen M. McCoy, Master Naturalist, AZNPS Phoenix Chapter Member

Leer en español

During early spring, the young Cirsium neomexicanum has already grown about 1 foot on its way to 6 feet in late summer. This prickly member of the Sunflower family (Asteraceae) is often considered a weed, unwanted, and dangerous. Before looking for a scythe, let’s take some time to evaluate this native desert plant.

Photo credit: Lisa Rivera

Common names for C. neomexicanum include New Mexico thistle, Desert thistle, Foss thistle, Lavender thistle, and Powderpuff thistle (Southwestern Desert Flora, 2020). It is scattered throughout most of Arizona as well as CA, CO, NM, NV, UT, and northwest Mexico, residing in multiple habitats, such as plains, hillsides, washes, roadsides, and even urban alleys.

From March to September, it produces pink, purple, lavender, or white fragrant and showy flowers up to 3 inches. The flower head is composed of many small flowers (florets) surrounded by modified or specialized leaves (brachts). The lower, outer brachts point downward, while the upper, inner bracts point upward and are somewhat twisted.

Photo credit: Lisa Rivera

True thistles have spines along the leaf margins (Sivinski, 2016). New Mexico thistle’s spiny green or greenish-gray leaves have the lobes arranged on either side of a central axis like a feather (pinnately lobed) and can be up to 7 inches long.

Arizona and New Mexico each have 19 species in the genus Cirsium (Southwest Desert Flora, 2020). Native thistles support a wide variety of native pollinator and plant-eating insects, such as bees, butterflies, and moths by providing important habitat and food sources. Because native Cirsium spp. can be annual, biennial, or perennial, their nectar can help support pollinators year-round. In addition to drawing nectar and pollen from the flowers, many insects feed on the leaves, stems, and seeds.

Also, many songbirds are attracted to thistle seeds. A symbiotic relationship exists between American goldfinches and native thistles. Seeds and thistle down are food and nest building components critical to the bird’s survival. The timing of seed production and thistle down is related directly to the goldfinch breeding season. Because thistles are late bloomers and American goldfinches breed late in the summer, these birds have an abundance of seeds and thistle down to line their nests (Deane, n.d.). In return, the birds spread the thistle seed to additional areas.

Like its cousin the artichoke, New Mexico thistle is edible! Thistle stalks and taproots are sources of food for humans, but harvesting time is critical. Before the flowering stalks emerge, the taproots of young first-year plants can be dug up. At this early stage, the roots are tender and can be eaten raw or chopped up and added to soups or stews. Their texture has been described as crisp and crunchy with an almost nutty flavor. The stalks can also be consumed, but must be harvested when they are only about 1 to 2 feet high. (Beyond about 2 feet high the stalks are too fibrous and tough to eat.) Stalks can be peeled and eaten fresh or as a cooked vegetable. No significant medicinal uses for New Mexico thistle have been documented (Kane, 2020).

Photo credit: Lisa Rivera

Most southwestern native thistles, including the New Mexico thistle, are non-aggressive and non-invasive (Karr, 2017). Native Cirsium spp. pose no fire risk and do not destructively displace native plants, thus remaining in equilibrium with other native flora. However, native thistles do reduce opportunity for invasive non-native thistles to populate a location.

Despite their benefits, native thistles are either knowingly or unknowingly killed simply because they are considered spiny “weeds.” In some areas, native thistle species are in danger of being complete eradicated. So, please, “stop before you chop!”


Deane, G. (n.d.) Thistle: It’s That Spine of Year.

Kane, C.W. (2020). Sonoran Desert food plants. Lincoln Town Press, USA.

Karr, L. (2017). Think Twice Before Killing Those Thistles: Thistle Identification.

Sivinski, R. (2016). New Mexico Thistle Identification Guide.

Southwest Desert Flora. (2020) Cirsium neomexicanum.,%20New%20Mexico%20Thistle.html

Invasive & Toxic Plants

Posted on Feb 01, 2021

The theme of the Winter 2020 issue of The Plant Press is invasive and toxic plants in Arizona. At our Chapter meeting in January, we had an engaging discussion about the articles and our experiences with invasive and toxic plants.

It was no surprise that most of us have experienced issues with stinknet (Oncosiphon pilulifer/piluliferum). To try to control stinknet on your property, our recommendation is to continually be on the lookout for it during the winter/spring season and take immediate action when you find seedlings. The top methods methods we’ve used to try to control stinknet and other invasives are:

  • manual removal;
  • hoeing or raking;
  • chemical herbicides;
  • applying a layer of mulch, landscape fabric, or cardboard; and
  • natural herbicides, such agricultural grade vinegar.


Stinknet plant flowering.

Stinknet plants flowering. Photo credit: Lisa Rivera

Oleander (Nerium oleander) is a toxic plant that has been problematic for some of us. We also felt more could be done to inform the public about which landscaping plants and weeds are toxic to humans and animals. Therefore, our Chapter plans to provide more information about toxic plants in the future.

Oleander plant in bloom.

Oleander is a common ornamental plant. Beware, it is poisonous to humans and animals. Photo credit: Lisa Rivera

If you couldn’t attend our meeting, you can still learn about Arizona’s invasive and toxic plants by reading the latest issue of The Plant Press, particularly pages 1-24 and 27-31. The publication is freely available to everyone.

Also, if you need help identifying the most prolific invasive species in our area, Desert Defenders has a useful invasive plant fact sheet.


See what your chapter has been up to!