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 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 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 this 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.
Plant Profile: Desert Globemallow
Posted on Jan 17, 2021
A Most Remarkable Native Plant
By Kathleen M. McCoy, Master Naturalist, AZNPS Phoenix Chapter Member
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What plant with stunning petals could you see growing in an alley, a xeriscape garden, and the Sonoran Desert? Most likely the correct guess is Sphaeralcea ambigua, more commonly known as desert globemallow or apricot mallow.
The genus Sphaeralcea (globemallows) contains about 50 plants primarily in North America, and most have flowers in the orange to red range. The most drought tolerant member is the desert globemallow. This largest-flowered globemallow blooms most heavily in the spring, but continues to flower through November. Each bowl-shaped flower has five petals that are up to 1.5 inches long. Once the flowers have faded, small green cups will form, sometimes containing hundreds of seeds. This low-maintenance plant will re-seed itself and can provide surprises in color production; the seed you plant one year may produce plants with a different color the next.
Desert globemallow in bloom. Photo credit: Lisa Rivera
This perennial subshrub’s foliage is a characteristic silvery color with tiny star-shaped wooly hairs, two adaptations that conserve moisture and reflect sunlight. With slightly woody stems restricted primarily to the crown, each desert globemallow grows in a large, rounded clump to a height of 20-40 inches, and may have over a hundred stems growing from the same root. Transplanting globemallows may be difficult and disappointing. The plant above ground may have lateral roots that extend three feet below the ground. If the root is not completely intact when digging up or putting the plant back into the earth, the plant may be mortally wounded.
Desert globemallows can be found in parts of AZ, CA, NM, NV, and UT, as well as Sonora and Baja California in Mexico. You will most likely find this plant growing in desert scrub below 3500 feet on dry, rocky slopes, edges of sandy washes, roadsides, and disturbed areas. It requires full sun and well-drained soil.
This drought-adapted plant can be used in range revegetation. Desert globemallow is an early colonizing species and may suppress invasive species in areas affected by fires. Seeds can be used on construction sites for erosion control or to restore the native plant community. Seedlings have been used to revegetate abandoned mine sites.
Although desert globemallow is edible, it unfortunately does not have a taste to match the brilliance of its flowers. However, it is a food source for the desert tortoise and provides browse for bighorn sheep and livestock. In addition, the large number of flowers produced throughout the year provides a steady source of pollen and nectar to many pollinators, such as hummingbirds, native bees, honeybees, butterflies, and moths.
The hardy desert globemallow has a prominent history in the Southwest. Its stems were used by the Yavapai to create trays for drying saguaro fruit or slabs of pounded mescal. Our ancestors also discovered that desert globemallow relieved and/or cured many disorders. Native Americans have used its leaves and roots to make medicine and eyewashes. Due to its high mucilage content, the plant has been used orally for coughs, colds, diarrhea, and the flu. As a poultice, globemallow has been applied to cuts, burns, snake bites, and swellings like rheumatism.
This lovely native plant is neither threatened nor endangered. The only “problem” is that once established, they and their abundant progeny may aggressively take residence in spaces reserved for other plants in the garden. Most desert globemallows spread by rhizomes. If you plan to contain them, be prepared to pull up lots of suckers. The desert is another matter; stand back and watch the plant spread its glowing blossoms as far as the eye can see.
Sources:
Lady Bird Johnson Wildflower Center. Plant Data Base: Sphaeralcea ambigua. https://www.wildflower.org/plants/result.php?id_plant=spam2
SEINnet. Sphaeralcea ambigua. https://swbiodiversity.org/seinet/taxa/index.php?tid=3800&taxauthid=1&clid=0
Water Use It Wisely. Plant of the Month: Globe Mallow. https://wateruseitwisely.com/plant-of-the-month-globe-mallow/
Top 20 Native Landscaping Plants for Phoenix
Posted on Nov 18, 2020
Our November Chapter meeting included a presentation about landscaping with native plants. A portion of this webinar is available to view, featuring our Chapter President’s Top 20 Native Landscaping Plants for Metro Phoenix.
We also invite you to view the Phoenix 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.
Hopefully the webinar and plant list will inspire to you to add more native plants to your own landscaping!
If you have any questions or are interested in participating in the Phoenix Chapter’s Native Plant List working group or focus group, please email aznpsphoenix@gmail.com.
