Pinaleño Mountains rubberweed facts for kids

Hymenoxys ambigens is a type of flowering plant. It belongs to the daisy family. People often call this plant the Pinaleño Mountains rubberweed. You can find it growing naturally in the southwestern United States, especially in Arizona and New Mexico.

What it Looks Like

This plant is a perennial herb. This means it lives for more than two years. It can grow quite tall, sometimes up to 150 centimeters (about 5 feet). Its leaves are very thin. They look a bit like branching threads.

One Hymenoxys ambigens plant can produce many small, yellow flowers. It might have anywhere from 25 to 400 flower heads! Each flower head has two types of tiny flowers. There are 3 to 5 "ray flowers" (these look like petals). There are also 6 to 15 "disc flowers" in the center.

Different Kinds of This Plant

Just like there can be different types of apples, there are different varieties of Hymenoxys ambigens. These varieties are slightly different versions of the same plant. They often grow in different places.

• Hymenoxys ambigens var. ambigens: This variety grows in places like Mescal, the Pinaleño Mountains, and the Santa Teresa Mountains in Arizona.
• Hymenoxys ambigens var. floribunda (A.Gray) W.L.Wagner: You can find this variety in the Chiricahua Mountains, Dos Cabezas Mountains, Dragoon Mountains, Little Dragoon Mountains, and Mule Mountains in Arizona.
• Hymenoxys ambigens var. neomexicana W. L. Wagner: This variety grows in the Animas Mountains and Peloncillo Mountains in New Mexico.

How it Was Discovered

In 1882, a botanist named Sara Plummer Lemmon found this plant species. Later, a botanist from Harvard University, Asa Gray, was the first to describe the species officially. He named it Plummera floribunda to honor her discovery. In 1994, scientists decided that Plummera should be considered a smaller group within the Hymenoxys genus.