Week 5 Plant Family: Alliaceae

Allium validum

The Alliaceae, or the onion family, has several defining characteristics:

  1. Bulbous Plants: the presence of bulbs, or underground storage structures. Bulbs contain nutrients and allow plants to survive adverse environmental conditions.
  2. Onion/Garlic Odor: This odor is due to sulfur compounds present in the plants.
  3. Herbaceous Perennials: Members of this family do not have woody stems and can persist for multiple growing seasons.
  4. Linear or Strap-Shaped Leaves: long, linear or strap-shaped leaves arise from the base of the plant and have parallel leaf veins. These leaves can vary in size and shape depending on the species.
  5. Umbel Inflorescence: The flowers of Alliaceae plants are typically arranged in umbels, which are umbrella-like clusters of small individual flowers. These flowers can be white, pink, or purple, depending on the species.
  6. Six Petals and Six Stamens: The flowers of Alliaceae typically have six petals and six stamens. The petals are often similar in appearance and arranged in two whorls of three.
  7. Fruit Capsules: After flowering, Alliaceae plants produce dry, three-chambered capsules that contain the seeds. These capsules split open when mature to release the seeds.
  8. Edible and Culinary Importance: Onions, garlic, leeks, chives, and shallots are common examples.
  9. Medicinal and Traditional Uses: Some Alliaceae species, particularly garlic, have been used for their potential medicinal properties, which include antioxidant and antimicrobial effects.

Link to a video showing the characteristics of vegetables in the Alliaceae.

Week 4 Plant Family: Lamiaceae

The Lamiaceae, commonly known as the mint family, is a family of flowering plants that includes many well-known herbs and aromatic plants. Here are some characteristics of the Lamiaceae:

  1. Square Stems: When you roll the stem between your fingers, you can feel the four distinct edges.
  2. Opposite Leaves: Leaves are typically arranged in pairs on the stem, with each pair of leaves located opposite each other.
  3. Aromatic Oils: Aromatic oils give them their characteristic scents and flavors. Examples: mint, basil, oregano, and rosemary.
  4. Tubular Flowers: The flowers often have bilateral symmetry, meaning they can be divided into two equal halves along one plane.
  5. Inflorescence: Flowers are arranged in spikes, whorls, or clusters, forming an inflorescence. This arrangement is often seen in the form of a spike or a head at the top of the stem.
  6. Fruit: Composed of four small nutlets or seeds, often enclosed by the persistent calyx (the sepals).
  7. Glandular Trichomes: Plants have hairs with glands that secrete aromatic oils and can be seen as small dots or bumps on the leaves and stems.
  8. Culinary and Medicinal Uses: Often used for culinary purposes, such as herbs and spices, and for their medicinal properties. Valued for their aromatic and flavorful qualities as well as their potential health benefits.
  9. Diverse Genera: The family is quite diverse and includes a wide range of genera. Some well-known genera within this family include Mentha (mint), Salvia (sage), Thymus (thyme), Rosmarinus (rosemary), and Ocimum (basil), among others.
  10. Worldwide Distribution: Lamiaceae plants can be found in various parts of the world, with many species adapted to different climates and regions.

Jepson video showing characteristics of the Lamiaceae.

CNPS video showing a presentation on the genus Salvia.

Week 3 Plant Family: Geraniaceae

Geraniaceae is a family of flowering plants that includes a wide range of species commonly known as geraniums or cranesbills. Here are several defining characteristics:

  1. Leaves: The leaves of Geraniaceae plants are usually palmately lobed or divided. This means that the leaves have several distinct lobes or leaflets radiating from a single point of attachment, often resembling the shape of a hand.
  2. Flowers: The flowers of Geraniaceae are typically five-petaled and have a radial symmetry. They can vary in color, including shades of pink, purple, white, and red. The petals are often veined, and the flowers are usually hermaphroditic, meaning they have both male and female reproductive parts.
  3. Fruits: The fruit of Geraniaceae plants is a distinctive structure known as a schizocarp. This fruit consists of five segments that split apart when mature, each containing a seed. When the segments split, they can resemble a crane’s bill, which is how the common name “cranesbill” for some species in this family originated.
  4. Sepals: The sepals of Geraniaceae flowers are typically fused to form a tubular or bell-shaped structure called the calyx. The calyx often has pointed lobes and surrounds the base of the petals.
  5. Inflorescence: The flowers of Geraniaceae are usually arranged in umbels, which are clusters of flowers that radiate from a single point on the stem.
  6. Glandular Hairs: Many species in this family have glandular hairs on their leaves and stems, which can produce aromatic compounds.
  7. Aromatic Foliage: Some members of Geraniaceae are known for their aromatic foliage, which can release pleasant fragrances when touched or crushed. This is particularly characteristic of scented geraniums (Pelargonium species).
  8. Stipules: Many Geraniaceae species have stipules at the base of their leaves. Stipules are small, leaf-like structures that can be important for classification.

Here’s a screenshot of the key to genera within the Geraniaceae from the Jepson eFlora:

Erodium cicutarium, a non-native invasive species in the Geraniaceae.

Click here for a video showing the characteristics of the Geraniaceae.

Week 2 Plant Family: Brassicaceae

The Brassicaceae, also known as the mustard family, is the second plant family of the week.

Caulanthus californicus, the CA jewelflower, is an endangered species in the Brassicaceae.
Brassica nigra, a non-native, invasive species, is also in the Brassicaceae.

The Brassicaceae includes a wide variety of plants, many of which are commonly cultivated for their edible parts (e.g., broccoli, cabbage, mustard) or for their ornamental value. These plants share several characteristics:

  1. Four-petal flowers: Members of the Brassicaceae family typically have flowers with four petals arranged in the shape of a cross. This arrangement is often referred to as “cruciform” and is a key characteristic of the family.
  2. Six stamens: Flowers typically have six stamens, including four long stamens and two shorter ones.
  3. Alternate leaves: The leaves are usually arranged alternately along the stem, rather than in opposite pairs.
  4. Seed pods (siliques or silicles): Fruits can take the form of siliques (long, narrow, and cylindrical) or silicles (shorter and wider than siliques). The seeds are arranged in a row within these pods.
  5. Pinnate or pinnatifid leaves: Many Brassicaceae plants have leaves that are either pinnate (feather-like) or pinnatifid (deeply lobed), often with a waxy or glaucous appearance.
  6. Peppery taste: Some members of the Brassicaceae family, such as mustard and radish, are known for their peppery or spicy taste due to the presence of compounds like glucosinolates.
  7. Herbaceous growth: Most Brassicaceae plants are herbaceous, do not develop woody stems, and tend to have a relatively short lifespan.
  8. Worldwide distribution: Brassicaceae plants are found in various parts of the world, from temperate regions to alpine habitats. They are well adapted to a range of environmental conditions.
  9. Economic importance: Many members of the Brassicaceae family are of economic importance as food crops, oilseed crops (e.g., canola), and ornamental plants.

Click here for the Jepson Manual key to the Brassicaceae in California.

Click here for a video introducing the Brassicaceae.