Question: Arctostaphylos and Thalia, are both plants?

Context paragraphs:
Arctostaphylos densiflora: Arctostaphylos densiflora, known by the common name Vine Hill manzanita, is a very rare species of manzanita.  It is endemic to Sonoma County, California, where it is known from only one extant population of 20 to 30 individual plants.  These last wild members of the species are on land near Sebastopol which is owned and protected by the California Native Plant Society.  In addition, there are five to ten plants of this manzanita taxon growing on private property about a mile away.  The local habitat is mostly chaparral on sandy shale soils.

Mary Bowerman: Mary Leolin Bowerman (January 25, 1908 – August 21, 2005) was an American botanist, co-author of "The Flowering Plants and Ferns of Mount Diablo, California; Their Distribution and Association into Plant Communities""," and the co-founder of Save Mount Diablo.  She helped to preserve tens of thousands of acres of Mount Diablo in the San Francisco East Bay before dying at age 97.  In 1936 she was the last person to record the Mount Diablo buckwheat "Eriogonum truncatum," until it was rediscovered nearly seventy years later on May 10, 2005.  In 1978 the manzanita "Arctostaphylos bowermaniae" was named in her honor.

Thalia (plant): Thalia is a genus of six currently recognized species found in aquatic or marshy habitats, ranging in Africa from Senegal to Sudan to Zimbabwe, and in the Americas from Illinois to Argentina.  Alligator-flag is a common name for plants in this genus.  The generic name is in honor of Johannes Thal (1542–1583), a German doctor who wrote a Flora of the Harz Mountains.

Arctostaphylos: Arctostaphylos ( ; "arkto" bear + "staphyle" grape) is a genus of plants comprising the manzanitas ( ) and bearberries.  They are shrubs or small trees.

Arctous: Arctous is a genus of plants referred to by the common name "bearberry", a name sometimes shared with certain species of the related genus "Arctostaphylos", in particular, "A. uva-ursi".  Although the two genera are related, certain leaf characters, such a rugose-reticulate venation and fine teeth are more typical of "Arctous" than "Arctostaphylos".

Osmia ribifloris: Osmia ribifloris, one of several species referred to as a blueberry bee, is a megachilid bee native to western North America, including Oregon, California, Nevada, Utah, Arizona, New Mexico, Texas and northern Mexico.  This solitary bee normally gathers pollen from plants in the family Ericaceae, with manzanita, "Arctostaphylos sp."  being a preferred host in the wild.  It will pollinate blueberries, and is sometimes used commercially for this purpose.

Supporting paragraphs: Arctostaphylos Thalia (plant)
Answer: yes